JP2007019529A - Device for forming semiconductor thin film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for forming a semiconductor thin film which projection-exposes an exposure pattern formed on a photo-mask onto a semiconductor thin film on a substrate mounted on a substrate stage, and for upgrading the quality of a given region of the semiconductor thin film. <P>SOLUTION: A device for forming a semiconductor thin film projection-exposes an exposure pattern formed on a photo-mask onto a semiconductor thin film on a substrate mounted on a substrate stage, and upgrades the quality of a given region of the semiconductor thin film. The exposure pattern is sequentially scanned by driving separately the photo-mask or the substrate stage. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a silicon thin film used for a crystalline silicon thin film transistor and an apparatus for forming a high-quality semiconductor-insulating film interface for application to a field effect transistor. The present invention also relates to an apparatus for manufacturing a semiconductor thin film such as a silicon compound such as silicon germanium (SiGe) or silicon carbide (SiC) using a pulsed laser beam, or a compound semiconductor such as GaAs, GaN, CuInSe ₂ , or ZnSe. Furthermore, the present invention relates to an apparatus for manufacturing a driving element or a driving circuit such as a display or a sensor constituted by the semiconductor thin film or the field effect thin film transistor.

Typical techniques for forming a thin film transistor (TFT) on a glass substrate include a hydrogenated amorphous silicon TFT technique and a polycrystalline silicon TFT technique. The former has a maximum manufacturing process temperature of about 300 ° C. and realizes a carrier mobility of about 1 cm ² / Vsec. This technology is used as a switching transistor for each pixel in an active matrix type (AM) liquid crystal display (LCD), and is driven by a driver integrated circuit (IC, LSI formed on a single crystal silicon substrate) arranged around the screen. Is done. Since each pixel is provided with a switching element TFT, it has a feature that crosstalk and the like can be reduced and good image quality can be obtained as compared with a passive matrix LCD that transmits an electric signal for driving liquid crystal from a peripheral driver circuit. On the other hand, the latter can obtain a carrier mobility of 30 to 100 cm ² / Vsec by using a high temperature process similar to an LSI of about 1000 ° C. using a quartz substrate, for example. The realization of such high carrier mobility is a manufacturing process in which, for example, when applied to a liquid crystal display, the pixel TFT for driving each pixel and the peripheral drive circuit section can be simultaneously formed on the same glass substrate. There are advantages relating to cost reduction and downsizing. This is because the connection pitch between the AM-LCD substrate and the peripheral driver integrated circuit is narrowed by downsizing and high resolution, and the tab connection or wire bonding method cannot cope with it. However, in the polycrystalline silicon TFT technology, when the high temperature process as described above is used, an inexpensive low softening point glass that can be used by the former process cannot be used. Therefore, it is necessary to reduce the temperature of the polycrystalline silicon TFT process, and a technique for forming a polycrystalline silicon film at a low temperature by applying a laser crystallization technique is being researched and developed.

  In general, these laser crystallizations are realized by a pulse laser irradiation apparatus having a configuration as shown in FIG. Laser light supplied from the pulsed laser light source 1101 is irradiated through an optical path 1106 defined by mirrors 1102, 1103, 1105 and an optical element group such as a beam homogenizer 1104 installed to make the spatial intensity uniform. The silicon thin film 1107 on the glass substrate 1109 which is a body is reached. Since one irradiation range is generally smaller than that of a glass substrate, laser irradiation is performed on an arbitrary position on the substrate by moving the glass substrate on the xy stage 1109. Instead of the xy stage, it is possible to move the above-described optical element group or to combine the optical element group and the stage.

  FIG. 6 of Non-Patent Document 1 shows that the substrate is placed on the x-direction stage and the homogenizer is placed on the y-direction stage.

  Laser irradiation may be performed in a vacuum chamber or in a high purity gas atmosphere in a vacuum chamber. In addition, if necessary, it has a cassette 1110 containing a glass substrate with a silicon thin film and a substrate transport mechanism 1111, and the substrate can be mechanically taken out and stored between the cassette and the stage.

Further, Patent Document 1 discloses a technique in which an amorphous silicon thin film on an amorphous substrate is crystallized by irradiating a short wavelength pulse laser beam and applied to a thin film transistor. According to this method, it is possible to crystallize amorphous silicon without increasing the temperature of the entire substrate. Therefore, a semiconductor element or a semiconductor integrated circuit is manufactured on a large area such as a liquid crystal display and an inexpensive substrate such as glass. There is an advantage that you can. However, as described in Patent Document 1, the irradiation intensity of about 50 to 500 mJ / cm ² is required for crystallization of the amorphous silicon thin film by the short wavelength laser. On the other hand, the light emission output of currently available pulse laser devices is about 1 J / pulse at maximum, and the area that can be irradiated at one time is only about ² to 20 cm ² even by simple conversion. Therefore, for example, in order to laser-crystallize the entire substrate size of 47 × 37 cm, it is necessary to irradiate at least 87 to 870 locations with laser. If the substrate size is increased, such as a 1 m square, the number of irradiation points is similarly increased. In general, these laser crystallizations are realized by the pulse laser irradiation apparatus having the structure shown in FIG. 1 as described above.

  In order to uniformly form a thin film semiconductor element group on a large-area substrate by the above method, the element group is divided smaller than the laser beam size as disclosed in Patent Document 2, and step and repeat are performed. It is known that a method of repeating several pulse irradiation + movement of irradiation region + several pulse irradiation + movement of irradiation region +... Is effective. As shown in FIG. 2B, this is a method in which laser oscillation and stage (ie, substrate or beam) movement are performed alternately. However, when a pulsed laser apparatus having an oscillation intensity uniformity of about ± 5 to 10% (during continuous oscillation), which is currently available by this method, is used, for example, when irradiation of about 1 pulse / location to about 20 pulses / location is repeated, oscillation occurs. There was a problem that the intensity variation exceeded ± 5 to 10%, and the resulting polycrystalline silicon thin film and polycrystalline silicon thin film transistor characteristics did not have sufficient uniformity. In particular, the generation of strong light or weak light, which is called spiking, due to instability of discharge at the early stage of laser oscillation is a problem of non-uniformity. In order to perform this correction, the method of controlling the applied voltage at the next oscillation based on the integrated intensity result has a problem in that weak light is oscillated, although spiking can be suppressed. That is, as shown in FIG. 3, when the irradiation time and the non-oscillation time are alternately continued, the first pulse intensity oscillated at each irradiation time is the most unstable and likely to vary, and the irradiation is performed depending on the irradiation location. Since the strength histories are different, there is a problem that sufficient uniformity of the transistor elements and the thin film integrated circuit in the substrate surface cannot be obtained. As a method for avoiding such spiking, as shown in FIG. 2A, there is known a method for avoiding laser oscillation by starting laser irradiation before the start of irradiation of the element formation region. When laser oscillation and stage movement as shown in (2) are repeated intermittently, there is a problem that it cannot be applied. Furthermore, in order to avoid these problems, Patent Document 3 proposes a method of continuously oscillating a pulse laser light source and preventing irradiation of the substrate using a light shielding device during the stage movement period. That is, as shown in FIG. 2 (3), the laser is continuously oscillated at a certain frequency, and the movement of the stage to the desired irradiation position and the shielding of the optical path are synchronized, so that the laser beam having a stable intensity can be applied to the desired irradiation position. Enabled irradiation. However, according to this method, although it is possible to irradiate a stable substrate with a laser beam, useless laser oscillation that does not contribute to the formation of a polycrystalline silicon thin film increases, and the lifetime of an expensive laser light source or excitation gas is reduced. Since the productivity of the polycrystalline silicon thin film and the production efficiency of the polycrystalline silicon thin film with respect to the power required for laser oscillation and the like are lowered, there is a problem that the production cost is increased. Further, the substrate to which the laser is exposed also causes substrate damage when excessively strong light is irradiated as compared with a desired value due to variations in irradiation intensity. In an imaging device such as an LCD, there is a problem in that light transmitted through the substrate causes scattering or the like in a damaged area on the substrate, resulting in a decrease in image quality.

  Non-patent document 2 and non-patent document 3 disclose techniques for reducing and projecting a pattern on an optical mask onto a silicon thin film for laser crystallization. According to this document, a reduced projection of about 1: 5 using a 308 nm excimer laser, variable-energy attenuator, variable-focus field lens, patterned-mask, two-element imaging lens, sub-micrometer-precision translation stage. By doing so, a beam size of the order of μm and a moving pitch of the substrate stage of the order of μm are realized. However, when this method is used for large substrate processing as described above, the laser beam irradiated on the optical mask has a spatial intensity profile that depends on the light source. There is a problem that a critical intensity distribution is generated in the exposed pattern, and a crystalline silicon thin film having a desired uniformity cannot be obtained. Furthermore, since the ultraviolet light having a short wavelength is reduced and projected, the depth of focus of the beam is small, and there is a problem that the irradiation depth shift is likely to occur due to the warp or deflection of the substrate. Further, as the substrate becomes larger, it is difficult to ensure the mechanical accuracy of the stage, and there is a problem that the tilt of the stage and the displacement of the substrate on the stage during the movement hinder the desired laser irradiation conditions.

  A method of irradiating a plurality of pulses with a certain delay time when performing laser irradiation as described above is disclosed in Non-Patent Document 4. According to this, the crystallization and solidification rate of molten silicon in the laser recrystallization process is 1 m / sec or more, and it is necessary to reduce the solidification rate in order to obtain good crystal growth. By irradiating the second laser pulse immediately after the solidification is completed, a recrystallization process with a lower solidification rate can be obtained by the second irradiation. Now, according to the temperature change (time history curve) of silicon as shown in FIG. 4, the temperature of silicon rises with the irradiation of laser energy (for example, the intensity pulse shown in FIG. 5), and the starting material is a-Si. When the temperature further rises after the melting point of a-Si and the supply of energy falls below a value necessary for the temperature rise, cooling starts. At the freezing point of the crystalline Si, after solidification is completed after the solidification time, it is cooled to the ambient temperature. Here, if the solidification of silicon proceeds in the film thickness direction starting from the silicon-substrate interface, the average value of the solidification rate is expressed by the following equation.

Average value of solidification rate = silicon film thickness / solidification time More specifically, if the silicon film thickness is constant, it is effective to increase the solidification time in order to reduce the solidification rate. Therefore, if the process maintains the ideal state in terms of thermal equilibrium, the solidification time can be extended by increasing the ideal energy to be input, that is, the laser irradiation energy. However, as pointed out in the above-mentioned known documents, there is a problem that an increase in irradiation energy causes the film to become amorphous or microcrystalline. In an actual melting / recrystallization process, an ideal temperature change as shown in FIG. 4 is not shown, and a stable state is reached through a supercooling process during heating and a supercooling process during cooling. This is because, in particular, when the cooling rate during cooling is large and excessive supercooling is performed, crystallization near the freezing point does not occur, and an amorphous (amorphous) solid is formed by rapid cooling and solidification. As described in Non-Patent Document 4 above, the thin film may form a microcrystal rather than an amorphous depending on conditions. A microcrystal has an extremely small grain size compared to a polycrystalline thin film or a single crystal thin film, and therefore there are many crystal grain boundaries with a large grain boundary potential. There is a problem that current increases.

  On the other hand, the technology to perform the a-Si thin film forming process, laser irradiation process, plasma hydrogenation process, and gate insulating film forming process in order or in sequence, without exposure to the atmosphere, is the following: In the patent literature.

  Patent Document 4: After a heat treatment of an amorphous semiconductor thin film, a step of irradiating a laser is performed without exposing to the atmosphere.

  Patent Document 5: A substrate having a laser-crystallized polycrystalline silicon thin film is transported to a plasma hydrogenation and gate insulating film forming step without being exposed to the atmosphere.

  Patent Document 6: A substrate having a laser-crystallized polycrystalline silicon thin film is transported to a gate insulating film forming step without being exposed to the atmosphere.

  Patent Document 7: A substrate having a laser-crystallized polycrystalline silicon thin film is transported to a gate insulating film forming step without exposing the substrate to the atmosphere to prevent impurities from adhering to the polycrystalline silicon surface.

  Patent Document 8: Amorphous silicon thin film formation, laser crystallization, hydrogenation, and gate insulating film formation are continuously performed without exposure to the atmosphere.

  Patent Document 9: Amorphous silicon thin film formation, laser crystallization, hydrogenation, and gate insulating film formation are continuously performed without exposure to the atmosphere.

  Patent Document 10: Amorphous silicon thin film formation, laser crystallization, hydrogenation, and gate insulating film formation are continuously performed without exposure to the atmosphere.

  Patent Document 11: Amorphous silicon thin film formation, laser crystallization, gate insulating film formation, and gate electrode formation are continuously performed without exposure to the atmosphere.

These thoughts and techniques are that the silicon surface formed by laser crystallization is very active, so that it is easy for impurities to adhere to it when exposed to the atmosphere, resulting in deterioration of the characteristics of the resulting TFT, or It has been devised to solve the problem of causing variations in characteristics. Therefore, the applicants performed excimer laser crystallization technology and silicon oxide film formation technology in the same device (including transporting the substrate to another device without exposing it to the atmosphere), and compared the performance with the case where it was once exposed to the air Went. As a result, it was found that although the yield rate of the product was greatly improved by the effect of preventing the adhesion of dust and particles, this effect was obtained to some extent by increasing the cleanliness of the clean room environment. In order to improve the yield rate, a substrate cleaning mechanism incorporated in the same apparatus is more effective than a film forming apparatus. For example, depending on the formation conditions of the a-Si formation process, particles may adhere to the substrate during film formation, and once released into the atmosphere, a cleaning process is required. On the other hand, when focusing on the performance of the thin film transistor, the difference in the manufacturing process did not bring about a significant difference. The reason for this can be considered as follows. The present applicants, for example, in Non-Patent Document 5, a silicon oxide film formed using plasma at a temperature of about 300 to 350 ° C. or a fixed oxide film of a silicon oxide film formed through a heat treatment of about 600 ° C. A charge density (10 ¹¹ to 10 ¹² cm ⁻² ) and an interface state density (˜6 × 10 ¹⁰ cm ⁻² eV ⁻² ) between the silicon substrate and the silicon substrate are disclosed. In this case, the silicon substrate is generally acidified such as sulfuric acid / hydrogen peroxide solution, hydrochloric acid / hydrogen peroxide solution / water, ammonia / hydrogen peroxide solution / water, hydrofluoric acid / water, which is called RCA cleaning (heating as necessary). ) After using a cleaning solution and washing with water, it is introduced into the film forming apparatus. Therefore, although the interface state density value is a single crystal silicon substrate, the interface state density value is obtained from a sample which has been once exposed to the atmosphere after the formation (cleaning) of the clean interface and moved to the film forming process. Here, attention is focused on the trap level density of one of the laser crystallized silicon films. For example, Non-Patent Document 6 discloses the trap level density (10 ¹² to 10 ¹³ cm ⁻² ) in a crystallized silicon film from the thin film transistor having a laser crystallized silicon film. In addition, the field effect mobility exhibited by these transistors is as high as 40 to 140 cm ² / vsec.

  When the trap state density in the silicon film is compared with the interface state density (or fixed oxide film charge density), the value of the trap state density is clearly larger. That is, in a sample in which a silicon film / gate insulating film is formed in the same apparatus without being exposed to the atmosphere, the performance of the silicon film (trap level density) is not sufficient to obtain the cleanliness effect. Turned out to be.

Next, a remote plasma CVD (chemical vapor deposition) method has been proposed as a means for reducing plasma damage and forming a high-quality gate insulating film. For example, Patent Document 12 discloses a configuration in which a plasma generation chamber and a substrate processing chamber are separated. By adopting such a configuration, the low fixed oxide film charge density (10 ¹¹ to 10 ¹² cm ^-2 ) and the low interface state density (~ 6 x 10 ¹⁰ cm ^-2 eV ^-2 ) as described above can be obtained. Although it can be inferred that this can be realized, there is a problem that this effect is limited by the performance of the silicon film formed in advance as described above.

Japanese Patent Publication No.7-118443 Japanese Patent Laid-Open No. 5-211167 JP-A-5-90191 JP-A-5-182923 JP-A-7-99321 Japanese Patent Laid-Open No. 9-7911 Japanese Patent Laid-Open No. 9-17729 JP-A-9-148246 JP-A-10-116989 JP-A-10-149984 Japanese Patent Laid-Open No. 11-17185 JP-A-5-21393 J. Im and R. Sposili, Crystalline Si films for integrated active-matrix-liquid-crystal displays ", Materials Research Society Bulletin, vol. 21, (1996), 39 R. Sposili and J. Im, "Sequential lateral solidification of thin silicon films on SiO2", Applied Physics Letters, vol. 69, (1996), 2864 J. Im, R. Sposili and M. Crowder, "Single-crystal Si films for thin film transistor devices", Applied Physics Letters, vol. 70, (1997), 3434 Ryoichi Ishihara et al. "Effects of light pulse duration on excimer laser crystallization characteristics of silicon thin films", Japanese journal of applied physics, vol. 34, No.4A, (1995) pp1759 K. Yuda et al. "Improvement of structural and electrical properties in low-temperature gate-oxides for poly-Si TFTs by controlling O2 / SiH4 ratios", Digest of technical papers 1997 international workshop on active matrix liquid crystal displays, September 11- 12, 1997, Kogakuin Univ., Tokyo, Japan-, 87 H. Tanabe et al., "Excimer laser crystallization of amorphous silicon films", NEC Research and Development, vol. 35, (1994), 254

  An object of the present invention is to provide a technique for forming a semiconductor thin film having a small trap level density by light irradiation in order to overcome the above-described problems and to apply the technique on a large area substrate with good reproducibility. The technology / apparatus is provided.

  Another object of the present invention is to provide means for forming a high-quality gate insulating film on these high-quality semiconductor films, and to manufacture a field effect transistor having a good semiconductor-insulating film interface, that is, excellent characteristics. To provide an apparatus.

  (1) According to the present invention, a semiconductor thin film forming apparatus which modifies a predetermined region of a semiconductor thin film by projecting and exposing an exposure pattern formed on an optical mask onto a semiconductor thin film on a substrate held on a substrate stage. The semiconductor thin film forming apparatus is characterized by having a mechanism for sequentially scanning the exposure pattern by individually driving the optical mask or the substrate stage. When the area that can be projected and exposed on the substrate by the optical mask is smaller than the substrate size, the substrate is moved to the exposure region by the substrate stage. By sequentially moving the mask stage in accordance with the laser irradiation while the substrate is fixed, the desired area is exposed.

  (2) According to the present invention, an exposure pattern formed on an optical mask is projected and exposed onto a semiconductor thin film, and the exposure pattern is projected onto the semiconductor thin film in a semiconductor thin film forming apparatus for modifying a predetermined region of the semiconductor thin film. In this case, a semiconductor thin film forming apparatus having a focusing mechanism for focusing the exposure pattern on a predetermined region of the semiconductor thin film can be obtained. When the substrate is moved to the exposure area by the substrate stage, it is focused on the center of the substrate and the periphery of the substrate due to substrate warpage, deflection, thickness variation, or deviation of the perpendicularity to the exposure axis of the substrate stage. Even if a deviation from the position occurs, desired exposure can be performed on the entire surface of the substrate with good reproducibility by performing focusing at any time.

  (3) According to the present invention, in a semiconductor thin film forming apparatus for modifying a predetermined region of a semiconductor thin film by projecting and exposing a pattern formed on an optical mask onto the semiconductor thin film with an exposure beam, the exposure beam is applied to the semiconductor thin film. A semiconductor thin film forming apparatus having an inclination correction mechanism for correcting the inclination is obtained. When moving the substrate to the exposure area using the substrate stage, exposure is performed at the center of the substrate and the periphery of the substrate due to substrate warpage, deflection, variation in thickness, etc., or deviation in the perpendicularity to the exposure axis of the substrate stage. Even if a deviation from the axis occurs, desired correction can be performed on the entire surface of the substrate with high reproducibility by correcting the tilt as needed.

  (4) According to the present invention, a semiconductor film is deposited in a semiconductor thin film forming apparatus for modifying a predetermined region of a semiconductor thin film by projecting and exposing a pattern formed on an optical mask onto the semiconductor thin film with an exposure beam. A semiconductor thin film forming apparatus having an alignment function for aligning an exposure beam with respect to a mark formed on a substrate can be obtained. By determining the exposure region based on the alignment mark provided in advance, a semiconductor thin film that has been exposed and modified under desired exposure conditions can be formed at a desired location. For example, only the channel region of a transistor is exposed and modified. Can be quality. That is, corresponding to the modified region, the source / drain and channel regions can be sequentially formed in the following process.

  (5) According to the present invention, in a semiconductor thin film forming apparatus for modifying a predetermined region of a semiconductor thin film by projecting and exposing a pattern formed on an optical mask onto the semiconductor thin film, the substrate on which the semiconductor film is deposited is staged. A semiconductor thin film forming apparatus characterized by having a function of holding on is obtained. When the area that can be projected and exposed on the substrate by the optical mask is smaller than the substrate size, the substrate is moved to the exposure region by the substrate stage. By sequentially moving the mask stage in accordance with the laser irradiation while the substrate is fixed, the desired area is exposed. In such a case, the substrate on the stage is displaced due to movement of the substrate stage or the like. In particular, when rotation correction (θ correction) is required, it is necessary to hold the substrate because correction is performed every time a deviation occurs, which hinders throughput. Further, when the substrate is heated on the stage, the substrate is warped or bent by the heating, thereby preventing the occurrence of defocus or tilt from the exposure axis.

  (6) According to the present invention, in a semiconductor thin film forming apparatus for modifying a predetermined region of a semiconductor thin film by projecting and exposing a pattern formed on an optical mask onto the semiconductor thin film with an exposure beam, a plurality of laser beams are emitted from the laser thin film. A semiconductor thin film forming apparatus having a synthesizing mechanism for synthesizing as an exposure beam is obtained.

  (7) According to the present invention, in the semiconductor thin film forming apparatus according to (6), the plurality of laser beams are first and second laser beams, and the synthesizing mechanism includes the first laser beam. On the other hand, a semiconductor thin film forming apparatus characterized in that the first and second laser lights are combined as the exposure beam so that the second laser light is irradiated to the semiconductor thin film with a delay.

Figure 6 shows the maximum cooling rate (Cooling rate, K / sec) obtained from numerical calculation and the SEM observation of the film after laser irradiation when an excimer laser with a wavelength of 308 nm is irradiated onto a 75 nm-thick silicon thin film. The threshold value of irradiation intensity of crystallization-microcrystallization is shown. FIG. 5 shows the emission pulse waveform of the laser used in the experiment. It has three main peaks and the emission time is about 120 nsec. Since such a pulse waveform has a light emission time that is five times or more that of the rectangular pulse having a pulse width of 21.4 nsec described in Non-Patent Document 6, the non-patent document described above can be used even with single pulse irradiation. The effect of reducing the solidification rate as described in 6 can be expected. Now, a temperature-time curve of silicon obtained from numerical calculation at the time of laser recrystallization using such a pulse waveform is as shown in FIG. FIG. 7 shows the temperature change of the silicon thin film when the silicon film thickness is 75 nm and the substrate is irradiated with SiO 2 and XeCl laser (wavelength 308 nm) at 450 mJ / cm ² . About 60 nsec after the second emission peak is almost completed, the maximum temperature is reached and cooling starts. (In this numerical calculation, the value of amorphous silicon is used as the melting and freezing point, and the behavior near the freezing point is different from the actual one. In particular, when a crystallized film is obtained, the crystalline silicon is crystallized at the freezing point. The cooling is once started with a large gradient, but it can be seen that the gradient of about 100 nsec where the third peak exists is very small. After 120 nsec when light emission is completely completed, it solidifies again through a rapid cooling process. In general, in the case of a solidification process from a liquid that has undergone “quenching” that greatly deviates from the thermal equilibrium process, sufficient solidification time necessary to form a crystal structure cannot be obtained, and an amorphous solid is formed. . FIG. 6 shows the result of estimating the maximum cooling rate after the end of light emission for each irradiation intensity from the temperature-time curve of silicon as shown in FIG. It can be seen that the cooling rate increases as the irradiation intensity increases. On the other hand, when the structure of the silicon thin film after laser irradiation was observed using a scanning electron microscope, although the particle size once increased with increasing irradiation intensity, microcrystallization was performed under a setting irradiation intensity condition of about 470 mJ / cm ² . Was observed. Similarly, when the number of irradiation pulses is set to 3, even under the setting irradiation intensity condition of about 470 mJ / cm ² , although the microcrystallized region remains partially, the particle size increases dramatically unlike the case of 1 pulse. Observed (FIG. 8). Since the actual irradiation intensity is higher by about 5 to 10% than the set value in the first few pulses of the excimer laser, the threshold intensity at which microcrystallization occurs can be estimated to be about 500 mJ / cm ² . From the above results, it was found that by estimating the cooling rate from the condition of 500 mJ / cm ² in FIG. 6, microcrystallization occurs at a cooling rate of about 1.6 × ^{10 10} ° C./sec or more. When the irradiated film is a-Si, microcrystallization occurs at an irradiation intensity of about 500 mJ / cm ² or more. Similarly, when this cooling rate is applied when the irradiated film is poly-Si, compared to a-Si. An irradiation intensity of about 30 mJ / cm ² is suggested. Therefore, by controlling the cooling rate to 1.6 × ^{10 10} ° C./sec or less, microcrystallization and amorphization can be prevented, and a good crystal growth process can be obtained.

  A case where the second laser beam is introduced with a delay to the first laser beam will be described. As already described, the laser light in the late stage of light emission moderates the increase in cooling rate, and the cooling rate after the end of light emission dominates crystallization. That is, it is considered that the previous cooling process is initialized by the energy finally input. Furthermore, by adding additional energy, energy is preserved even if amorphization or microcrystallization due to rapid cooling occurs in the previous solidification process (because of nanosecond order and short time, the substrate is It is considered that the heat conduction and the radiation to the atmosphere are small. (Of course, the time during which sufficient heat can be released is not taken into account.) Therefore, good crystal growth can be expected by paying attention to the cooling rate after the end of the secondary heating by the energy input again. As shown in FIG. 9, the cooling rate is controlled to a desired value by controlling the delay time.

Now, the spatial intensity distribution of the irradiated beam will be described next. Even in laser irradiation using a plurality of slits, it is desirable that the spatial distribution in the slits is constant and the intensity spatial distribution between the slits is constant, but due to limitations in optical element design and optical element fabrication, ± several % To about 10 to several tens%. In consideration of changes in the excimer laser light with time, wear of the optical system, adhesion of foreign matter to the optical element, the distribution may be ± several tens of percent. FIG. 10 shows an average crystal grain size d (d = KN ⁿ , where K is a constant and n is a constant, which depends on the irradiation intensity and the number of irradiations (number of irradiation pulses) N, obtained from a micrograph as shown in FIG. Change). As suggested by FIG. 10, the gradient n of the particle size change with respect to the number of irradiations N changes at the irradiation intensity of about 450 mJ / cm ² . When designing the desired fabrication conditions with the irradiation intensity and the number of irradiations N per place, do not mix the condition where the spatial intensity distribution is n = 1/4 and the condition where n = 1/7. It is desirable. Accordingly, even when spatial variation occurs, for example, a range of 521 to 470 mJ / cm ² (a range within about ± 5.2% of the average intensity 495.5 mJ / cm ² ) or a range of 424 to 339 mJ / cm ² ( If irradiation is performed so that the distribution falls within the range of about ± 11.2% of the average intensity of 381.5 mJ / cm ² ), the laser crystallization of the Si thin film in which the difference in the extreme average particle diameter is suppressed is possible. .

  (8) According to the present invention, in the semiconductor thin film forming apparatus having the processing chamber for modifying the predetermined region of the semiconductor thin film by projecting and exposing the pattern formed on the optical mask onto the semiconductor thin film on the substrate, A semiconductor thin film forming apparatus having a mechanism for transporting a substrate to another processing chamber without being exposed to the atmosphere can be obtained.

  (9) According to the present invention, in the semiconductor thin film forming apparatus according to the above (8), the another processing chamber is an insulating film forming chamber for forming an insulating film on a substrate. A forming device is obtained.

  Since the trap state density in the semiconductor film is equal to or less than the interface state density, it is possible to maintain the cleanliness by forming the semiconductor film / gate insulating film in the same device without exposure to the atmosphere. It is possible to obtain a good semiconductor-insulating film interface by fully utilizing the effect.

  (10) According to the present invention, in the semiconductor thin film forming apparatus according to (8), the another processing chamber is a semiconductor film forming chamber for forming a semiconductor film on a substrate. A forming device is obtained.

  (11) According to the present invention, in the semiconductor thin film forming apparatus according to (8), the another processing chamber is a heat treatment chamber for performing heat treatment on the substrate. Is obtained.

  (12) According to the present invention, in the semiconductor thin film forming apparatus according to the above (8), the another processing chamber is a plasma processing chamber for performing plasma processing on the substrate. Is obtained.

  (13) According to the present invention, in the semiconductor thin film forming apparatus according to (8), the processing chamber projects and exposes a pattern formed on the optical mask onto the semiconductor thin film on the substrate with a laser beam. A semiconductor thin film forming apparatus is obtained, which is a laser processing chamber for modifying the predetermined region of the semiconductor thin film, and the other processing chamber is another laser processing chamber.

  By adopting such a configuration, it is possible to provide a high-performance, multifunctional semiconductor forming apparatus, a low-cost, highly reproducible thin film transistor manufacturing process, and a high-performance thin film transistor.

In particular,
1) Providing highly stable semiconductor thin film process equipment that can reduce the cleaning process using chemicals 2) By providing a multi-function device that can process multiple processes in the same equipment, the total factory installation area can be reduced. Provision of a space-saving semiconductor process apparatus 3) A low-cost and high-performance thin-film transistor manufacturing method capable of maintaining a silicon clean surface (interface) without using a chemical solution can be provided.

  (14) According to the present invention, in the semiconductor thin film forming apparatus according to any one of (8) to (12), the another processing chamber generates plasma in a predetermined region in the other processing chamber. The semiconductor thin film forming apparatus is characterized in that the substrate is disposed in a region outside the predetermined region in the another processing chamber.

  (15) According to the present invention, in the semiconductor thin film forming apparatus according to the above (12), the another processing chamber has a plasma generation source for generating plasma in a predetermined region in the other processing chamber. Then, the other processing chamber reacts the gas excited by the plasma in the predetermined region with another gas introduced into the other processing chamber without passing through the predetermined region, A semiconductor thin film forming apparatus characterized in that the plasma treatment is performed on the substrate.

  In addition to means for reducing plasma damage and forming a good quality gate insulating film by separating the plasma generation chamber and the substrate processing chamber, the trap state density in the silicon film is equal to or less than the interface state density. Therefore, a good semiconductor-insulating film interface can be obtained.

  The effects of the present invention are listed below.

(1) In a semiconductor thin film forming apparatus for modifying a predetermined region of a semiconductor thin film by projecting and exposing an exposure pattern formed on the optical mask onto a semiconductor thin film on the substrate held on the substrate stage, the optical mask or the substrate As a result of sequentially scanning the exposure pattern by driving the stages individually or simultaneously, any region on the substrate can be sequentially reformed with high throughput. Even when applied to an imaging device such as an LCD, it has become possible to prevent damage to the substrate due to variations in the intensity of the light source, and thereby deterioration in image quality. In addition, it has become possible to provide a crystallized silicon film having a trap level density lower than 10 ¹² cm ^-2 .

  (2) An exposure pattern when projecting and exposing an exposure pattern onto a semiconductor thin film in a semiconductor thin film forming apparatus for projecting and exposing an exposure pattern formed on an optical mask onto a semiconductor thin film and modifying a predetermined region of the semiconductor thin film By providing a focusing mechanism for focusing the semiconductor thin film on the predetermined region, it was possible to provide a semiconductor thin film forming apparatus with high reliability and reproducibility of the modification process.

  (3) Inclination correction for correcting the inclination of the exposure beam with respect to the semiconductor thin film in a semiconductor thin film forming apparatus that modifies a predetermined region of the semiconductor thin film by projecting and exposing a pattern formed on the optical mask onto the semiconductor thin film with an exposure beam. By having the mechanism, it was possible to provide a semiconductor thin film forming apparatus with high reliability and reproducibility of the modification treatment.

  (4) In a semiconductor thin film forming apparatus for modifying a predetermined region of a semiconductor thin film by projecting and exposing the pattern formed on the optical mask onto the semiconductor thin film with an exposure beam, the pattern is formed on the substrate on which the semiconductor film is deposited. By providing an alignment function for aligning the exposure beam with respect to the mark, it is possible to expose a desired region with a positional accuracy of the order of μm or more. Even when applied to an imaging device such as an LCD, it has become possible to prevent damage to the substrate due to variations in the intensity of the light source, and thereby deterioration in image quality.

  (5) In a semiconductor thin film forming apparatus for projecting and exposing a pattern formed on an optical mask onto a semiconductor thin film to modify a predetermined region of the semiconductor thin film, a function of holding the substrate on which the semiconductor film is deposited on the stage As a result, it was possible to provide a semiconductor thin film forming apparatus with high reliability and reproducibility of the modification treatment.

  (6) A composition in which a plurality of laser beams are combined as the exposure beam in a semiconductor thin film forming apparatus that projects and exposes a pattern formed on an optical mask onto a semiconductor thin film with an exposure beam to modify a predetermined region of the semiconductor thin film. By having a mechanism, it was possible to modify a high-quality semiconductor thin film with high uniformity in a desired region where a pattern is exposed. At the same time, it has become possible to sequentially modify an arbitrary region on the substrate with high throughput.

  (7) In the semiconductor thin film forming apparatus forming apparatus according to (6), the plurality of laser beams are first and second laser beams, and the synthesizing mechanism has a second function for the first laser beam. By synthesizing the first and second laser lights as the exposure beam so that the laser light is delayed and irradiated onto the semiconductor thin film, high uniformity and high quality can be obtained in a desired region where the pattern is exposed. The semiconductor thin film could be modified. At the same time, it has become possible to sequentially modify an arbitrary region on the substrate with high throughput.

  (8) In a semiconductor thin film forming apparatus for projecting and exposing a pattern formed on an optical mask onto a semiconductor thin film on a substrate to modify a predetermined region of the semiconductor thin film, the substrate is placed in another processing chamber without being exposed to the atmosphere. By providing a semiconductor thin film forming device having a mechanism for transporting semiconductors, a semiconductor thin film having a high quality and chemically active surface equivalent to that of a single crystal semiconductor thin film can be transferred to the next process without being contaminated by impurities or dust. As a result, the semiconductor device manufacturing cost can be reduced by reducing the cleaning process, and the throughput can be improved by reducing the exhaust time and cleaning time in each vacuum apparatus.

(9) The semiconductor thin film forming apparatus forming apparatus according to (8), wherein the another processing chamber is an insulating film forming chamber for forming an insulating film on a substrate. As a result, a semiconductor thin film having a high quality and chemically active surface equivalent to that of a single crystal semiconductor thin film can be sent to the gate insulating film formation process without being contaminated by impurities and dust. Manufacturing of a semiconductor device having a good semiconductor-insulator interface as formed at the interface with oxidation was realized by a low-temperature process of 600 ° C. or lower. A crystallized silicon film having a trap state density lower than 10 ¹² cm ^-2 can be provided, and a silicon-insulator film interface having a low interface state density can be provided.

  (10) A semiconductor thin film forming apparatus according to (8), wherein the another processing chamber is a semiconductor film forming chamber for forming a semiconductor film on a substrate. Thus, the semiconductor film necessary for forming a semiconductor thin film having a high quality and chemically active surface equivalent to that of a single crystal semiconductor thin film is sent to the light irradiation process without being contaminated by impurities and dust. As a result, the semiconductor device manufacturing cost can be reduced by reducing the cleaning process, and the throughput can be improved by reducing the exhaust time and the cleaning time in each vacuum apparatus.

  (11) In the semiconductor thin film forming apparatus forming apparatus described in (8) above, it is possible to obtain a semiconductor thin film forming apparatus, wherein the another processing chamber is a heat treatment chamber for performing heat treatment on the substrate. did it.

  (12) A semiconductor thin film forming apparatus according to (8), wherein the another processing chamber is a plasma processing chamber for performing plasma processing on a substrate. Makes it possible to send a semiconductor thin film with a high quality and chemically active surface equivalent to that of a single crystal semiconductor thin film to the next process without being contaminated by impurities or dust. Through the reduction of cost and the reduction of exhaust time and cleaning time in each vacuum device, the throughput could be improved.

  (13) In the semiconductor thin film forming apparatus forming apparatus according to (8), the processing chamber projects and exposes a pattern formed on the optical mask onto the semiconductor thin film on the substrate with a laser beam, and By providing a semiconductor thin film forming apparatus, which is a laser processing chamber for modifying the predetermined region, and the another processing chamber is another laser processing chamber, Semiconductor thin films with the same high-quality and chemically active surface can be sent to the next process without being contaminated by impurities and dust, reducing the manufacturing cost of semiconductor devices by reducing the cleaning process, and each vacuum Throughput can be improved by reducing exhaust time and cleaning time in the equipment.

  (14) In the semiconductor thin film forming apparatus according to (8) to (12), the another processing chamber includes a plasma generation source for generating plasma in a predetermined region in the other processing chamber. By providing a semiconductor thin film forming apparatus in which a substrate is disposed in a region outside the predetermined region in the another processing chamber, a single unit sent to the next process without being contaminated by impurities or dust. It has been achieved to suppress plasma damage to semiconductor thin films with high quality and chemically active surfaces equivalent to crystalline semiconductor thin films.

  (15) In the semiconductor thin film forming apparatus according to (8) to (12), the another processing chamber has a plasma generation source for generating plasma in a predetermined region in the other processing chamber, The another processing chamber reacts the gas excited by the plasma in the predetermined region with another gas introduced into the other processing chamber without passing through the predetermined region. Semiconductor device manufacturing having a good semiconductor-insulator interface formed at the interface between silicon and silicon thermal oxidation by providing a semiconductor thin film forming apparatus characterized in that the plasma treatment is performed on Was realized by a low-temperature process of 400 ° C. or lower.

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 11 is an example showing an embodiment of the present invention. The pulsed UV light supplied from the first excimer laser EL1 and the second excimer laser EL2 is guided to the homogenizer opt20 ′ via mirrors opt3 and opt3 ′ and lenses opt4. Here, the beam intensity profile is shaped by the optical mask opt21 so as to have a desired uniformity, for example, in-plane distribution ± 5%. (The intensity profile and total energy of the original beam supplied from the excimer laser may vary from pulse to pulse, so the intensity on the optical mask is more uniform in terms of spatial distribution and variations between pulses. It is desirable that a mechanism using a fly-eye lens or a cylindrical lens is generally used as a homogenizer.) The light pattern formed by the optical mask is a reduction projection exposure apparatus opt23 ', The sub0 substrate placed in the vacuum chamber C0 is irradiated through the laser introduction window W0. The substrate is placed on the substrate stage S0, and the optical pattern can be exposed to a desired region, for example, the pattern transfer region ex0, by the operation of the substrate stage. Although the reduction projection optical system is shown in FIG. 11, enlargement projection may be performed at the same magnification in some cases. Irradiation is performed on an arbitrary region on the substrate by moving the substrate stage (X-Y in the figure). Further, the optical mask is placed on a mask stage (not shown), and it is also possible to operate the beam irradiated onto the substrate by moving the optical mask as long as it is within the exposure area.

  Next, a mechanism necessary for irradiating a substrate with a desired light pattern under desired conditions will be exemplified. Since the adjustment of the optical axis requires delicate adjustment, a method for adjusting the position of the substrate by fixing the optical axis that has been adjusted once will be described. The position of the substrate irradiation surface with respect to the optical axis needs to correct the position in the focal (Z) direction and the perpendicularity to the optical axis. Therefore, among the θxy inclination correction direction, θxz inclination correction direction, θyz inclination correction direction, X exposure area movement direction, Y exposure area movement direction, and Z focusing direction in the figure, θxy inclination correction direction, θxz inclination correction direction, θyz The degree of perpendicularity to the optical axis is corrected by adjusting the tilt correction direction. In addition, by adjusting the Z focusing direction, the substrate irradiation surface is arranged and controlled at a position corresponding to the focal depth of the optical system.

  FIG. 12 illustrates a side view of the above adjustment and substrate alignment mechanism. An optical mask opt21, a reduced projection exposure apparatus opt23 ′, and a laser introduction window W0 are arranged as shown in the figure with respect to the exposure axis L0. The substrate sub0 disposed in the vacuum chamber C0 is disposed on the heater H0 with a substrate suction mechanism and the substrate XYZθxyθxzθyz stage S0 ′. Although a vacuum chamber is used, actual light irradiation is preferably performed in an atmosphere of inert gas, hydrogen, oxygen, nitrogen or the like replaced after evacuation, and the atmospheric pressure may be about atmospheric pressure. Good. By using a heater with a substrate adsorption mechanism, substrate heating conditions of about room temperature to 400 ° C. can be selected during light irradiation. By setting the atmospheric pressure to the atmospheric pressure as described above, the substrate can be adsorbed by the vacuum chuck function, so that the displacement can be prevented even if the substrate stage moves in the chamber. Even if there is sled or deflection, it can be fixed to the substrate stage. Further, it is possible to minimize the depth of focus shift due to the warp or deflection of the substrate due to heating.

  The laser interferometers i1 and i2 measure the alignment of the substrate and the position in the Z direction of the substrate through the measurement window Wi and the measurement mirror opt-i. For alignment, an alignment mark on the substrate is measured using an off-axis microscope m0, a microscope light source Lm, and a microscope element opt-m, and a desired exposure position can be measured using substrate position information obtained by a laser interference system. Although the off-axis method is illustrated in FIG. 12, the Through The Lens method and the Through The Mask (Reticle) method can also be applied. Further, by determining linear coordinates from a plurality of measurement points using the least square method, it is possible to take means for averaging measurement errors that occur during measurement.

  FIGS. 13A to 13C show the relationship between the mask pattern and the alignment mark. The mask includes a mask (non-exposed portion) mask1 and a mask (exposed portion) mask2. For example, when an excimer laser is used as a light source, a film that absorbs and reflects ultraviolet light, such as a metal such as aluminum, chromium, and tungsten, or a dielectric multilayer film, is formed on a quartz substrate that transmits ultraviolet light. Is used to form a pattern. The silicon film is exposed in accordance with a desired pattern on the mask (indicated by a white portion in FIG. 13A), and an exposed Si portion (non-exposed Si (Si1)) (as shown in FIG. 13B). Si2) is formed. At this time, it is possible to expose a predesigned position on the silicon thin film by performing exposure after alignment adjustment so that the mark on the mask mark1 matches the mark on the substrate mark2 as necessary. Further, in the thin film transistor forming process using the silicon thin film, when the exposure process is the first process that requires positioning (that is, when the alignment mark is not formed in advance), the exposure forming mark mark3 is formed during the silicon thin film exposure process. By simultaneously exposing these, an alignment mark using the optical color difference between a-Si and crystalline Si can be formed. Therefore, a transistor, a desired mechanism, and a function can be formed in a desired region subjected to exposure modification by performing photolithography or the like in a later process using this mark as a reference. FIG. 13C shows a state where a Si oxide film is formed on the silicon thin film after the exposure process and a desired region of the silicon layer is removed by etching. The Si removal part (Si3) is a region where the laminated silicon film and Si oxide film are removed by etching. The Si oxide film (Si4, Si5) is laminated on the unexposed Si (Si1) and exposed Si (Si2). The shape is shown. Thus, by forming an island-shaped structure made of a silicon film covered with an oxide film, channel / source / drain regions of thin film transistors separated between elements and marks necessary for alignment in subsequent steps can be formed.

  14 (1) and 14 (2) show timing charts of main operations. In Control Example 1, the substrate is moved to a desired exposure position by the operation of the substrate stage. Next, focusing and alignment operations are performed to precisely adjust the exposure position. At this time, for example, adjustment is made so as to fall within a desired setting error accuracy such as about 0.1 μm to 100 μm. When the operation is completed, light irradiation to the substrate is performed. When these series of operations are completed, the substrate moves to the next exposure region, and after irradiation of necessary portions on the substrate is completed, the substrate is replaced and a predetermined series of processing is performed on the second processing substrate. . In Control Example 2, the substrate is moved to a desired exposure position by the operation of the substrate stage. Next, focusing and alignment operations are performed to precisely adjust the exposure position. At this time, for example, adjustment is made so as to fall within a desired setting error accuracy such as about 0.1 μm to 100 μm. When the operation is completed, the operation of the mask stage is started. In order to avoid variation in the amount of movement step at the start, the light irradiation to the substrate is a chart that is started after the start of the mask stage operation. Of course, since exposure is performed at a point away from the alignment position due to the movement of the stage, it is needless to say that the amount of offset needs to be considered in advance. It is also possible to start the operation of the light source earlier than the light irradiation to the substrate, and when the stability of the output intensity of the light source increases, the shutter or the like is opened to perform the light irradiation to the substrate. In particular, when an excimer laser is used as a light source and a usage method in which an oscillation period and a stop period are repeated, it is known that the initial several tens of pulses are particularly unstable. When it is not desired to irradiate the beam, a method of blocking the beam in accordance with the operation of the mask stage can be adopted. When these series of operations are completed, the substrate moves to the next exposure region, and after irradiation of necessary portions on the substrate is completed, the substrate is replaced and a predetermined series of processing is performed on the second processing substrate. .

An a-Si thin film with a thickness of 75 nm was scanned with a 1 mm × 50 μm beam at a 0.5 μm pitch in the minor axis direction. When a single light source was used and the laser irradiation intensity was 470 mJ / cm ^{2 on the} irradiated surface, a single crystal silicon thin film continuous in the scanning direction was obtained. In addition, a single crystal silicon thin film continuous in the scanning direction was obtained even under a scanning pitch condition of 1.0 μm under the condition that the second light source was irradiated with a delay of 100 nsec so that the irradiation surface was 150 mJ / cm ² . The trap level density in the crystallized silicon film was lower than 10 ¹² cm ^-2 .

  FIG. 15 is a side view of a semiconductor thin film forming apparatus showing an embodiment of the present invention. Consists of a plasma CVD chamber C2, a laser irradiation chamber C5, and a substrate transfer chamber C7, and the transfer of the substrate through the gate valves GV2 and GV5 does not touch the atmosphere outside the apparatus in vacuum, inert gas, nitrogen, hydrogen, oxygen Etc., and in a high vacuum, reduced pressure, and pressurized state. In the laser irradiation chamber, a substrate is set using a chuck mechanism on an S5 substrate stage that can be heated to about 400 ° C. In the plasma CVD chamber, the substrate is placed on the substrate holder S2 that can be heated to about 400 ° C. In this example, a silicon thin film (Si 1) formed on a glass substrate Sub0 is introduced into a laser irradiation chamber, and the silicon thin film on the surface is modified to a crystalline silicon thin film (Si 2) by laser irradiation, and plasma CVD is performed. The state conveyed to the chamber is shown.

  The laser beam introduced into the laser irradiation chamber is such that the beam supplied from the excimer laser 1 (EL 1) and the excimer laser 2 (EL 2) passes through the first beam line L 1 and the second beam line L 2. Laser synthesis optical device opt 1, mirror opt 11, transmission mirror opt 12, laser irradiation optical device opt 2, homogenizer opt 20, optical mask opt 21 fixed to optical mask stage opt 22, projection optical device opt 23, laser introduction window It reaches the substrate surface via W1. Although two excimer lasers are illustrated here, one or more desired number of light sources can be installed. In addition to the excimer laser, a pulse laser such as a carbon dioxide laser or a YAG laser, or a CW light source such as an argon laser and a high-speed shutter may be used to supply the pulse.

  On the other hand, in the plasma CVD chamber, the plasma formation region D2 is formed at a position away from the region where the substrate is disposed by the RF electrode D1 and the plasma confinement electrode D3. A silicon oxide film can be formed on the substrate by supplying, for example, oxygen and helium to the plasma formation region and silane gas using the source gas introduction device D4.

  FIG. 16 is a plan view of a semiconductor thin film forming apparatus showing an embodiment of the present invention. The load / unload chamber C1, the plasma CVD chamber C2, the substrate heating chamber C3, the hydrogen plasma processing chamber C4, the laser irradiation chamber C5, and the substrate transfer chamber C7 are connected through gate valves GV1 to GV6, respectively. The laser beam supplied from the first beam line L1 and the second beam line L2 is irradiated onto the substrate surface via the laser synthesis optical device opt1, the laser irradiation optical device opt2, and the laser introduction window W1. In addition, gas introduction devices gas1 to gas7 and exhaust devices vent1 to vent7 are connected to the respective process chambers and transfer chambers, and supply of desired gas species, setting of process pressure, exhaust, and vacuum are adjusted. As shown by dotted lines in the figure, the processing substrates sub2 and sub6 are arranged on a plane.

FIG. 17 is a schematic view of the plasma CVD chamber C2. Power is supplied to the high frequency electrode RF2 from a high frequency power source (high frequency of 13.56 MHz or higher is suitable) RF1. Plasma is formed between the electrode RF3 with a gas supply hole and the high-frequency electrode, and the radical formed by the reaction passes through the electrode with the gas supply hole and is guided to the region where the substrate is disposed. Another gas is introduced by the planar gas introducing device RF4 without being exposed to plasma, and a thin film is formed on the substrate sub2 through a gas phase reaction. The substrate holder S2 was designed to be heated from room temperature to about 500 ° C. with a heater or the like. Oxidation by reacting oxygen radicals and silane gas using exhaust device ven2, gas introduction device gas2, oxygen line gas21, helium line gas22, hydrogen line gas23, silane line gas24, helium line gas25, argon line gas26 as shown in the figure A silicon film can be formed. When film formation was performed under conditions of a substrate temperature of 300 ° C., a pressure of 0.1 torr, an RF power of 100 W, a silane flow rate of 10 sccm, an oxygen flow rate of 400 sccm, and a helium flow rate of 400 sccm, the fixed oxide film charge density (5 × 10 ¹¹ cm ⁻² ) was good. The formation of a silicon oxide film having characteristics is confirmed. Further, a better oxide film can be formed by increasing the ratio of oxygen flow rate to silane. As a form of the plasma CVD chamber, not only the parallel plate type RF plasma CVD apparatus as described above but also a method not using plasma such as low pressure CVD or atmospheric pressure CVD, or a microwave or ECR (Electron Cycrotron Resonance) effect was used. It is also possible to use a plasma CVD method.

Table 1 shows an example of gas types necessary when the plasma CVD apparatus shown in FIG. 17 is used for forming a thin film other than a silicon oxide film.

  For the formation of the Si3N4 silicon nitride film, N2 (nitrogen) (or ammonia), Ar (argon) as a carrier gas, SiH4 (silane), argon as a carrier gas, or the like can be used. A source gas such as H2 hydrogen and silane, hydrogen (argon as a carrier gas) and SiF4 tetrafluorosilane (argon as a carrier gas) can be used for forming the Si silicon thin film. Although not a film formation process, hydrogen plasma treatment of a silicon thin film or a silicon oxide film is also possible using hydrogen plasma.

  FIG. 18 is a process flow diagram when the semiconductor thin film forming apparatus of the present invention is applied to a thin film transistor manufacturing process.

  (a) A substrate cover film T1 and a silicon thin film T2 are sequentially formed on a glass substrate sub0 from which organic substances, metals, fine particles, and the like have been removed by cleaning. As a substrate cover film, a silicon oxide film of 1 μm is formed at 450 ° C. using silane and oxygen gas as raw materials by LPCVD (low pressure chemical vapor deposition). By using the LPCVD method, it is possible to cover the entire outer surface of the substrate except for the substrate holding region (not shown). Alternatively, plasma CVD using tetraethoxysilane (TEOS) and oxygen as raw materials, atmospheric pressure CVD using TEOS and ozone as raw materials, plasma CVD as shown in FIG. 18, and the like can be used. A material capable of preventing diffusion of impurities harmful to semiconductor devices including glass whose concentration is reduced as much as possible, quartz / glass whose surface is polished, and the like is effective as the substrate cover film. The silicon thin film is formed by LPCVD using disilane gas as a raw material at 500 ° C. and a thickness of 75 nm. In this case, since the concentration of hydrogen atoms contained in the film is 1 atomic% or less, film roughness due to hydrogen release in the laser irradiation process can be prevented. Alternatively, even if a plasma CVD method as shown in FIG. 17 or a widely used plasma CVD method is used, the hydrogen atom concentration is adjusted by adjusting the substrate temperature, the hydrogen / silane flow rate ratio, the hydrogen / 4 fluorinated silane flow rate ratio, or the like. Can form a silicon thin film with low thickness.

  (b) The substrate prepared in the step (a) is subjected to a cleaning step for removing organic substances, metals, fine particles, surface oxide films, and the like, and then introduced into the thin film forming apparatus of the present invention. Irradiation with the laser beam L0 modifies the silicon thin film into a crystallized silicon thin film T2 ′. Laser crystallization is performed in an atmosphere of high purity nitrogen of 99.9999% or higher and 700 torr or higher.

  (c) The substrate having undergone the above steps is transferred to the plasma CVD chamber through the substrate transfer chamber after the gas is exhausted. As the first gate insulating film T3, a silicon oxide film is deposited to a thickness of 10 nm at a substrate temperature of 350 degrees using silane, helium, and oxygen as source gases. Thereafter, hydrogen plasma treatment or heat annealing is performed as necessary. The processing up to this point is processed in the thin film forming apparatus of the present invention.

  (d) Next, an island of a silicon thin film and a silicon oxide film laminated film is formed using photolithography and etching techniques. At this time, it is preferable to select an etching condition in which the etching rate of the silicon oxide film is higher than that of the silicon thin film. As shown in the figure, a thin film transistor with high reliability can be provided by preventing gate leakage by forming the pattern cross section in a step shape (or taper shape).

  (e) Next, after performing cleaning for removing organic substances, metals, fine particles, etc., a second gate insulating film T4 is formed so as to cover the island. Here, a silane and oxygen gas were used as raw materials by LPCVD, and a silicon oxide film having a thickness of 30 nm was formed at 450 ° C. Alternatively, it is also possible to use plasma CVD using tetraethoxysilane (TEOS) and oxygen as raw materials, atmospheric pressure CVD using TEOS and ozone as raw materials, plasma CVD as shown in FIG. Next, an n + silicon film of 80 nm and a tungsten silicide film of 110 nm are formed as gate electrodes. The n + silicon film is preferably a crystalline phosphorus-doped silicon film formed by plasma CVD or LPCVD. Thereafter, a T5 patterned gate electrode is formed through photolithography and etching processes.

  (f1, f2) Next, impurity implantation regions T6, T6 ′ are formed using the gate as a mask. In the case of forming a CMOS type circuit, photolithography is used together to separately form an n-channel TFT that requires an n + region and a p-channel TFT that requires a p + region. Methods such as ion doping that does not perform mass separation of implanted impurity ions, ion implantation, plasma doping, and laser doping can be employed. At that time, impurities are introduced while leaving or removing the silicon oxide film on the surface as shown in (f1) and (f2) depending on the application and impurity introduction method.

  (g1) (g2) Interlayer isolation insulating films T7, T7 ′ are deposited, contact holes are opened, metal is deposited, and metal wiring T8 is formed by photolithography and etching. As the interlayer isolation insulating film, a TEOS-based oxide film, a silica-based coating film, or an organic coating film that can be flattened can be used. The contact hole opening can be applied by photolithography and etching, and the metal wiring can be applied with a low-resistance aluminum, copper, an alloy based on them, or a high melting point metal such as tungsten or molybdenum. By performing the above steps, a thin film transistor with high performance and reliability can be formed.

  19 shows an embodiment in which an alignment mark is provided in advance and laser irradiation corresponding to the alignment mark is performed, and FIG. 20 shows an embodiment in which an alignment mark is formed simultaneously with laser irradiation, based on the TFT manufacturing process flow. explain. Since it is basically similar to the description of FIG. 18, the description will focus on differences.

  FIG. 19 (a) A substrate cover film T1 and a tungsten silicide film are sequentially formed on a glass substrate sub0 from which organic substances, metals, fine particles and the like have been removed by cleaning. In order to form an alignment mark, patterning is performed by photolithography and etching, and an alignment mark T9 is formed on the substrate. Next, a mark protective film T10 is formed to protect the alignment mark, and a silicon thin film is formed.

  FIG. 19 (b) At the time of laser beam exposure, a desired area is exposed with reference to the alignment mark. Thereafter, the alignment of the next process can be performed based on an alignment mark provided in advance or an alignment mark (not shown) formed by crystallized silicon thin film patterning.

  In FIG. 20 (b), a crystallization alignment mark T9 ′ is formed on the silicon thin film using the difference in modification by exposure / non-exposure simultaneously with the exposure of the silicon thin film.

  FIG. 20 (d) Using the crystallization alignment mark T9 ′, alignment at the time of photolithography is performed, and an island of a silicon thin film and a silicon oxide film laminated film is formed through an etching process.

  FIG. 21 shows a laser annealing apparatus that performs laser annealing by heating an amorphous semiconductor with a synchronization pulse, a laser oscillation apparatus 3110 that generates laser light having a desired wavelength and waveform, and laser light from a laser generation unit 3110. Is provided with a laser irradiation processing unit 3120 that actually processes the substrate W, and a main controller 3130 that comprehensively controls these operations. The substrate W that is a workpiece is made of a glass plate or the like, and an amorphous Si layer that is an amorphous semiconductor, for example, is deposited on the surface thereof. In the case of a crystalline Si layer, this becomes a polycrystalline Si layer.

  The laser generation unit 3110 generates a pair of pulsed light beams with an appropriate time difference by individually controlling the oscillation timing of the pair of laser oscillation devices 3111 and 3112 that generate pulse-type laser light and the laser oscillation devices 3111 and 3112. And an oscillation control device 3113 which is a delay control unit. Here, the first laser oscillation device 3111 is a main laser device that is irradiated first when the substrate W is processed, and the second laser oscillation device 3112 is a secondary laser device that is irradiated next when the substrate W is processed. is there. Each laser beam from the first and second laser oscillation devices 3111 and 3112 is appropriately adjusted in time difference and power so as to be optimal for the processing of the substrate W, and the two pulsed lights PL are overlapped via the photosynthesis system 3170. By combining them, it becomes a synchronized pulse light for processing.

  The oscillation control device 3113 includes a computer, a signal shaping circuit, and the like, and presets a generation interval, that is, a time difference between a reference pulse generation circuit 3151 that generates a reference pulse and a pair of pulsed light PL that forms a synchronization pulse light. Based on the signal output from the delay time setting circuit 3152, the delay time setting circuit 3152, and the like, the operation timing of the first and second laser oscillation devices 3111 and 3112 is set, and an arithmetic circuit 3153 that generates a command signal corresponding thereto. A trigger pulse generation circuit 3154 that receives the output of the command signal from the arithmetic circuit 3153 and generates first and second trigger signals for oscillating the first and second laser oscillation devices 3111 and 3112; High-speed photoelectric conversion of the laser outputs of the second laser oscillators 3111 and 3112, respectively. First and second photosensors 3161 and 3162, a pair of amplifiers 3163 and 3164 for individually amplifying outputs from the first and second photosensors 3161 and 3162, and both amplifiers 3163 and 3164, respectively. And a delay time detection circuit 3155 for detecting a time difference between the two light detection signals in response to the light detection signal from the first light detection signal.

  The delay time setting circuit 3152 sets a time difference (hereinafter, set time difference t1) such that the waveform of the synchronization pulse obtained by superimposing the laser beams from the first and second laser oscillation devices 3111 and 3112 is optimal for processing the substrate W. Set. Such a set time difference t1 can be set by inputting from the outside via a keyboard or the like, or by reading a set value stored in advance according to the type of the substrate W.

  The arithmetic circuit 3153 generates a command signal S2 corresponding to the set time difference t1 set by the delay time setting circuit 3152. Further, based on the output of the measurement time difference t3 from the delay time detection circuit 3155, a correction time difference t2 obtained by correcting the set time difference t1 is calculated, and a command signal S2 'corresponding to the set time difference t2 is generated.

  The trigger pulse generation circuit 3154 receives the command signal S2 (S2 ′) output from the arithmetic circuit 3153, performs appropriate signal processing, and uses the reference pulse from the reference pulse generation circuit 3151 as a trigger to trigger the first and second laser oscillations. The first and second trigger signals Tr1 and Tr2 for causing the devices 3111 and 3112 to oscillate are generated by being shifted by a time difference t1 (t2), respectively.

  The delay time detection circuit 3155 cuts out a pair of light detection signals from both amplifiers 3163 and 3164 with a predetermined threshold, and outputs a pair of signals output from the first and second laser oscillation devices 3111 and 3112 based on the difference in rising timing. A delay time t3 between the laser beams is detected.

  Synchronous pulsed light emitted from the laser generator 3110 and synthesized through the photosynthesis system 3170 including the mirrors 3171 and 3172, the half mirror 3173, and the like is incident on the laser irradiation processing unit 3120. This laser irradiation processing unit 3120 has a projection optical system 3121 for projecting synchronous pulse light onto the substrate W as a beam having a desired cross-sectional shape and energy density distribution, and a stage 3122 that supports the substrate W and moves with the substrate W during scanning. And a stage drive system 3123 for controlling the operation of the stage 3122.

  Hereinafter, the operation of the laser processing apparatus of FIG. 21 will be described. The main controller 3130 controls the oscillation controller 3113 to generate a pair of pulsed lights PL that are shifted from the first and second laser oscillators 3111 and 3112 by a set time difference t1. Both pulsed lights PL are overlapped via the photosynthesis system 3170 and irradiated onto the substrate W as a synchronized pulsed light for processing having a predetermined waveform. Since the synchronization pulse light is generated using the reference pulse from the reference pulse generation circuit 3151 as a trigger, the irradiation of the synchronization pulse light onto the substrate W is repeated at a period corresponding to the period of the reference pulse.

  At this time, by monitoring the delay time t3 output from the delay time detection circuit 3155, it can be understood how much the actual delay time t3 is deviated from the set time difference t1, and the correction time difference t2 = t1 obtained by subtracting this deviation amount Δt. −Δt (= 2 × t1−t3) is set as a new target value. As a result, a pair of pulsed light PLs that are substantially shifted from the first and second laser oscillation devices 3111 and 3112 by the set time difference t1 can be generated. That is, when the delay time t3 ′ output from the delay time detection circuit 3155 exceeds a predetermined upper limit value or lower limit value due to factors such as response characteristics of the first and second laser oscillation devices 3111 and 3112 and changes with time, a new A corrected time difference t2 ′ = t1−Δt ′ obtained by subtracting the deviation amount Δt ′ is set as a new target value. By repeating the above, the time interval between the pair of pulsed lights PL constituting the synchronized pulsed light can always be kept constant. In other words, even if the characteristics of the laser oscillators 3111 and 3112 are different and there is a variation in the response time from trigger to light emission due to changes over time, changes in operating conditions, etc., synchronized pulsed light with a stable waveform can be obtained. Irradiation onto the substrate W is possible.

  FIG. 22 is a timing chart for explaining the operation timing of the apparatus shown in FIG. 22A shows the trigger signal Tr1 output from the waveform generators 3151 and 3154, FIG. 22B shows the pulsed light PL emitted from the first pulse laser oscillator 3111, and FIG. ) Shows the trigger signal Tr2 output from the trigger delay circuits 3153 and 3154, and FIG. 22 (d) shows the pulsed light PL emitted from the second pulse laser oscillator 3112. As can be seen from the figure, if the delay time Ts is set in the trigger delay circuits 3154 and 3152, the theoretical pulse time interval Td (= Td2-Td1 + Ts + Tc) is obtained.

  Next, a focus adjustment apparatus and method according to an embodiment of the present invention will be described.

  FIG. 23 is a diagram illustrating the overall structure of a laser annealing apparatus incorporating the focus adjustment apparatus of the embodiment. This laser annealing apparatus is for heat-treating a workpiece W, which is a workpiece in which a semiconductor thin film such as amorphous Si is formed on a glass plate, and excimer laser or other laser light AL for heating the semiconductor thin film. , An irradiation optical system 3720 that is a processing optical system that makes this laser light AL enter a line or a spot at a predetermined illuminance, and an X− A stage 3730 that can move smoothly in the Y plane and can be tilted around the X axis and the Y axis, and a stage 3730 on which the workpiece W is placed are moved or tilted by a necessary amount with respect to the irradiation optical system 3720 or the like. A stage driving device 3740 that is a driving means and a main control device 3780 that comprehensively controls the operation of each part of the laser annealing device are provided. That. Here, the stage 3730 and the stage driving device 3740 constitute a stage device, and are housed in a chamber 3790 for reducing the pressure around the workpiece W and adjusting the atmosphere thereof. The chamber 3790 is installed on the floor via a vibration isolation device 3792.

  Further, this laser annealing device is a focus adjustment device, in addition to the stage 3730, the stage driving device 3740, and the main control device 3780, and a movement amount measurement for detecting the movement amount of the stage 3730 as optical information and electrical information. It corresponds to the apparatus 3750, the inclination measuring apparatus 3760 for detecting the height and inclination amount of the stage 3730 with respect to the stage driving apparatus 3740 as optical information and electrical information, and the height and inclination amount of the workpiece W with respect to the irradiation optical system 3720. And a non-contact displacement meter 3770 for detecting a signal.

  Here, the irradiation optical system 3720 includes a homogenizer 3720a that uniformly distributes the laser beam AL incident from the laser light source 3710 via the mirror 3715, and a mask having a slit that narrows the laser beam AL that has passed the homogenizer 3720a into a predetermined beam shape. 3720b and a projection lens 3720c that projects the slit image of the mask 3720b on the workpiece W in a reduced scale. Note that the irradiation optical system 3720 is disposed so as to face the workpiece W through a transmission window 3790a provided in the chamber 3790, and is fixed to the chamber 3790 side by a member not shown.

  The stage driving device 3740 includes a tilt device 3742 that tilts the stage 3730 about the X axis and the Y axis, and a translation device 3744 that moves the stage 3730 together with the tilt device 3742 smoothly in the XY plane. Here, the tilt device 3742 includes three support members 3742a that accommodate a cylinder inside the bellows and can expand and contract to an arbitrary length, and a support member drive device 3742b that expands and contracts the support member 3742a. By adjusting the lengths of these three support members 3742a via the support member driving device 3742b, the inclination and distance of the stage 3730 with respect to the irradiation optical system 3720 can be finely adjusted as appropriate. That is, the position (distance) of the workpiece W with respect to the irradiation optical system 3720 in the Z-axis direction, the tilt angle θX around the X axis, and the tilt angle θY around the Y axis can be adjusted. Note that the three tilt measuring devices 3760 extending from the tilt device 3742 directly below the stage 3730 are eddy current sensors or electrostatic capacitance sensors. From these outputs, the stage 3730 is connected to the stage drive device 3740. It is possible to know exactly whether it is inclined to some extent.

  The non-contact displacement meter 3770 is a laser displacement meter, and a light projecting unit 3771 that is a light projecting unit that causes the inspection light DL to be incident on a flat area on the workpiece W as the measurement target T, and regular reflection light from the measurement target T. A light receiving unit 3772 that is a light receiving unit that receives the RL and outputs information on the incident position of the regular reflection light RL. The light projecting unit 3771 and the light receiving unit 3772 are arranged to face each other with the irradiation optical system 3720 interposed therebetween. That is, the light projecting unit 3771 emits the inspection light DL in a direction inclined by a predetermined angle with respect to the optical axis of the irradiation optical system 3720, and the light receiving unit 3772 inspects the optical axis of the irradiation optical system 3720. The reflected light RL traveling in the direction inclined by the predetermined angle in the direction opposite to the light DL is incident. The main controller 3780 also functions as a conversion unit that obtains a measurement value including information corresponding to the height of the measurement target T based on the information on the incident position detected by the light receiving unit 3772, and is a non-contact displacement meter 3770. Part of

  Here, the light projecting unit 3771 includes a light source that generates inspection light and a light projecting optical system, and causes a spot-shaped beam of the inspection light DL to enter the measurement target T on the workpiece W through the transmission window 3790a. On the other hand, the light receiving unit 3772 includes an imaging optical system that condenses the reflected light RL from the measurement target T and a line sensor that receives the reflected light RL after condensing. This line sensor extends in the direction perpendicular to the optical axis of the reflected light RL in the XZ plane, and utilizes the fact that the height position of the workpiece W has a linear relationship with the position detection signal from the line sensor. Then, a change in the height position of the workpiece W is detected. However, when the workpiece W is tilted with respect to the optical axis of the irradiation optical system 3720, the output of the non-contact displacement meter 3770 reflects not only the height position of the workpiece W but also the tilt of the workpiece W. Yes. Therefore, as will be described in detail later, when the tilt of the workpiece W is corrected once using the tilt device 3742 and the normal line of the workpiece W becomes parallel to the optical axis of the irradiation optical system 3720, the tilt device 3742 is configured. The three support members 3742a to be expanded and contracted by the same amount adjust the distance between the workpiece W and the irradiation optical system 3720.

  The measurement targets T1, T2, and T3 are arranged at the positions of the vertices of an equilateral triangle, and each is set at an equal distance from the machining area on the workpiece W (in the figure, the center of the workpiece W). Under the control of the translation device 3744, the inspection light DL from the light projecting unit 3771 can be sequentially incident on the measurement targets T1, T2, and T3 on the workpiece W. When correcting the tilt of the workpiece W, the tilt device 3742 is operated so as to average the outputs of the light receiving units 3772 at the respective measurement targets T1, T2, and T3. Note that the arrangement and number of the measurement targets T1, T2, and T3 can be changed as appropriate according to the required accuracy and the like. In particular, when there is a deformation such as a warp on the surface of the workpiece W, it is necessary to select three or more measurement targets in the vicinity of each target processing region. In addition, the measurement targets T1, T2, and T3 described above need only be flat surfaces, and it is not necessary to form specific marks as long as regular reflection light can be formed.

  Hereinafter, the operation of the laser annealing apparatus of this embodiment will be described. First, the workpiece W is transported and placed on the stage 3730 of the laser annealing apparatus. Next, the workpiece W on the stage 3730 is aligned with the irradiation optical system 3720 for guiding the laser beam AL for annealing. Next, while moving the mask 3720b of the irradiation optical system 3720 or appropriately moving the stage 3730 with respect to the irradiation optical system 3720, the laser light AL from the laser light source 3710 is changed into a line or a spot on the workpiece W. To enter. A thin film of amorphous semiconductor such as amorphous Si is formed on the work W, and a semiconductor thin film having excellent electrical characteristics is obtained by annealing and recrystallizing a desired region of the semiconductor by irradiation and scanning with laser light AL. Can be provided.

  The operation of aligning the height and inclination of the workpiece W on the stage 3730 with respect to the irradiation optical system 3720 will be described in more detail. First, three vertices of an equilateral triangle centering on the machining area are defined as measurement targets T1, T2, and T3. Under the control of the translation device 3744, the workpiece W is appropriately moved in the XY plane, and each measurement target T1, T2, T3 on the workpiece W is sequentially moved to the measurement point of the non-contact displacement meter 3770, and inspection from the light projecting unit 3771 is performed. The light DL is incident on each measurement target T1, T2, T3. The reflected light RL from each measurement target T1, T2, T3 is converted into a signal corresponding to the incident position by the light receiving unit 3772. Main controller 3780 obtains measurement values relating to the heights of measurement targets T1, T2, and T3 based on signals relating to the incident positions from light receiving portion 3772. The measurement results at the three points T1, T2, and T3 are considered to include an error due to the inclination, but here, they are ignored and the heights at the three points T1, T2, and T3 are the same. The tilt angle θX, θY of the workpiece W is adjusted by the tilt device 3742 so that Again, the workpiece W is appropriately moved in the XY plane by the translation device 3744, and the measurement values relating to the height are obtained for the respective measurement targets T1, T2, and T3 on the workpiece W. In this way, by repeating the height measurement of the three points T1, T2, and T3 and the adjustment of the tilt angle, the error in the height measurement due to the tilt is gradually reduced. When the measured values of the three points T1, T2, and T3 finally match, θX = 0 and θY = 0, and the inclination is zero. The height measurement value at any one point at this time is the height of the machining area on the workpiece W. Finally, the tilt device 3742 is operated as the Z stage, and the stage 3730, that is, the workpiece W is moved up and down until the target height is reached.

  Although the present invention has been described based on the above embodiments, the present invention is not limited to the above embodiments. For example, three or more non-contact displacement meters 3770 can be provided. In this case, each non-contact displacement meter 3770 can simultaneously measure three different workpieces W. As a result, the tilt of the workpiece W can be quickly corrected without the translation device 3744 moving the workpiece W.

  In the above-described embodiment, the tilt device 3742 is operated as the Z stage. However, the Z stage can be provided independently, and the tilt adjustment and the height adjustment of the workpiece W can be completely separated.

  Moreover, in the said embodiment, although the workpiece | work W shall have formed the semiconductor thin film in the glass substrate, the raw material of the workpiece | work W will not be ask | required if regular reflection light is obtained.

  In addition, the above-described focus adjusting apparatus is incorporated in a laser annealing apparatus that anneals the semiconductor layer on the workpiece W using the laser light AL. However, if the structure of the laser light source 3710, the irradiation optical system 3720, or the like is appropriately changed, the semiconductor material It is also possible to provide a pulse laser processing apparatus that can modify, cut, and weld various materials as well as annealing.

  FIG. 24 shows a schematic configuration of a multifunction machine to which the present invention is applied. Here, a CVD apparatus 3910 that performs a film forming process on a glass substrate (work) is used as a primary processing apparatus, and a laser annealing apparatus 3920 that performs laser annealing on a glass substrate that has been subjected to a film forming process is used as a secondary processing apparatus. The case where it will be described.

  The laser annealing apparatus 3920 includes a process chamber 3921 that can be sealed. In the process chamber 3921, a process stage 3922 for mounting a glass substrate 3901 subjected to film formation processing is installed. A transmission window 3923 for transmitting a laser beam from a laser irradiation system, which will be described later, is provided on the ceiling wall of the process chamber 3921. A laser irradiation system 3925 is configured by a gantry 3924 above the process chamber 3921.

  The laser irradiation system 3925 is for receiving the laser beam generated by the laser oscillator 3926 through the reflection mirror 3927, irradiating the glass substrate 3901 with a focus by shaping it into a predetermined cross-sectional shape. Here, only the configuration for the rectangular beam is shown, and the configuration for the long beam will be described later.

  As components for the rectangular beam, a mask stage 3928 on which a mask is mounted, an optical lens system 3929, a sensor 3930, and the like are provided. The sensor 3930 is for detecting the focal position of the beam on the glass substrate 3901 and is used to adjust the focal position with high accuracy.

  Such a laser annealing device 3920 is installed on the floor 3950 via a plurality of vibration isolation tables 3940 described later.

  The CVD apparatus 3910 and the process chamber 3921 are connected via a transfer chamber 3970 that houses a substrate transfer robot 3960 as a transfer mechanism. In particular, as shown in FIG. 25, the process chamber 3921 and the transfer chamber 3970 are connected by a bellows 3971. Note that a connection portion between the process chamber 3921 and the transfer chamber 3970 is a portion that holds the glass substrate in the CVD apparatus 3910 by the substrate transfer robot 3960 and transfers the glass substrate into the process chamber 3921. In order to maintain a constant pressure, it is necessary to shut off from the atmosphere, and the bellows 3971 performs its function. Further, the transfer chamber 3970 needs a gate valve mechanism to prevent the inside of the CVD apparatus 3910 and the process chamber 3921 from communicating with each other, but such a gate valve mechanism is well known. The illustration is omitted.

  Next, with reference to FIG. 26 and FIG. 27, the structure of the vibration isolation table 3940 which is the main part of the vibration isolation device according to the present invention will be described. In the vibration isolation table 3940, an upper base 4241 on which the process chamber 3921 is mounted and an air damper 4242 are connected via a vibration isolation rubber 4243. Compressed air from the compressor 4244 is supplied to the air damper 4242 via the control valve 4245. A piston portion 4246 that moves up and down according to the introduced compressed air and a first stopper member 4247 for defining the lower limit position of the piston portion 4246 during vibration are disposed in the air damper 4242. ing.

  The upper pedestal 4241 defines the on / off operation of the vibration isolation table 3940 and the upper limit position of the vibration isolation table 3940. Strictly speaking, the upper limit in the height direction of the container housing the air damper 4242 A second stopper member 4148 for defining the limit position is provided. On the other hand, the container that houses the air damper 4242 is provided with a position detector 4149 for detecting a relative distance from the second stopper member 4148. When the displacement amount of the container containing the process chamber 3921 or the air damper 4242 exceeds a predetermined allowable range, a part of the position detector 4149 is partially stopped as shown in FIG. Engage with member 4148 to limit.

  A detection signal from the position detector 4149 is sent to the control device 42100 as a feedback signal. The control device 42100 controls the control valve 4245 according to the relative distance between the second stopper member 4148 and the position detector 4149 indicated by the detection signal, and removes vibrations so as to remove the vibration of the process chamber 3921. The base 3940 is operated.

  In particular, when the control device 42100 detects that the relative distance is equal to or less than a predetermined value, for example, when a part of the position detector 4149 comes into contact with the second stopper member 4148, the control device 42100 stops and removes the control operation for the control valve 4245. Stop the vibration function. That a part of the position detector 4149 has come into contact with the second stopper member 4148 means that the vertical movement of the upper base 4241 or the pneumatic damper 4242 has reached a value exceeding the allowable range. The second stopper member 4148 is configured such that the position in the vertical direction can be changed by adjusting means such as a screw.

  As can be understood from the above description, each vibration isolation table 3940 controls the pressure of compressed air that determines vibration isolation performance when the relative distance between the second stopper member 4148 and the position detector 4149 changes. Has a feedback control function to eliminate vibration. When the vertical movement of the upper base 4241 or the pneumatic damper 4242 exceeds the allowable range, the feedback control function is disabled. The position of the second stopper member 4148 can be manually moved up and down, and the position at which the vibration isolation function is stopped can be arbitrarily set.

  That is, the function of the vibration isolation table 3940 is exhibited from the position where the piston member 4246 hits the first stopper member 4247 to the position where a part of the position detector 4149 hits the second stopper member 4148. If this distance is 200 μm, the vibration isolation table 3940 functions within a range of vertical movement of ± 100 μm.

  Here, the operation at the time of scanning with high accuracy using a rectangular beam will be described. When processing is performed using a rectangular beam, the vibration in the process chamber 3921 is mainly transmitted from the CVD apparatus 3910 or the floor 3950. This vibration has a maximum amplitude of ± several tens of μm, and the bellows 3971 is not greatly displaced due to scanning. Therefore, the relative distance between the second stopper member 4148 of the vibration isolation table 3940 and the position detector 4149 is set to, for example, 200 μm so that the vibration isolation function definitely works when scanning using the rectangular beam. Set it slightly larger than the expected displacement. In this case, vibration from the floor 3950 is absorbed by the plurality of vibration isolation bases 3940 by the feedback control function, and vibration from the CVD apparatus 3910 is absorbed by the bellows 3971.

  Next, the vibration isolation performance at the time of scanning with low accuracy using a long beam will be described. When processing is performed with a long beam, the process stage 3922 in the process chamber 3921 moves, so that the position of the center of gravity of the process stage 3922 in the process chamber 3921 is shifted, and the whole is easily inclined greatly. When the inclination is small, the vibration isolation function is the same as when processing with the rectangular beam. However, when the inclination is large, the second stopper member 4148 is limited and the vibration isolation table 3940 does not function. If the vibration isolation table 3940 does not function, the process chamber 3921 and the bellows 3971 are displaced together, so that the relative position of the process chamber 3921 and the bellows 3971 is not displaced, and the bellows 3971 is destroyed even if the displacement is large. Absent. Note that the scanning accuracy by the long beam does not greatly affect the scanning accuracy because it allows a vibration several tens of times that of the rectangular beam.

With reference to FIGS. 28 to 29, an embodiment of the mechanical configuration of the in-vacuum linear actuator mechanism according to the present invention will be described. Here, a configuration suitable for being placed in a vacuum chamber for laser annealing will be described. The vacuum chamber is symbolically shown by a broken line 43100 in FIG. 30, and any vacuum chamber that can be used in an atmosphere from atmospheric pressure to 1.0 × 10 ⁻⁶ Torr may be used.

  A stage base 4309 as a fixed base member is installed at the bottom of the vacuum chamber 43100. Y-axis linear bearings 4315 and 4320 are attached to the stage base 4309 so as to extend parallel to the Y-axis direction at remote positions. The Y-axis linear bearings 4315 and 4320 are for linearly guiding the Y-axis base 4314 combined thereon in the Y-axis direction. A pair of X-axis linear bearings 4307 are attached to the Y-axis base 4314 so as to extend in parallel to the X-axis direction at remote positions. The X-axis linear bearing 4307 is for linearly guiding the X-axis base 4306 combined on them in the X-axis direction. A trolley 4403 that supports a stage 4302 incorporating a heater for heating is attached to the X-axis base 4306, and a work (glass or the like) 4301 is placed on the stage 4302.

  The X-axis base 4306 is driven by a pair of X-axis linear motors 4408 provided on the Y-axis base 4314 adjacent to the X-axis linear bearing 4307. The position of the X-axis base 4306 is detected by an X-axis linear encoder 4410 installed on the Y-axis base 4314 adjacent to one X-axis linear motor 4408. As a result, the X-axis base 4306 is directly driven and the position is directly measured, so that there is no deterioration in accuracy due to the conventional backlash and high-speed response is possible.

  The Y-axis base 4314 is driven by two linear motors 4318 and 4323 which are provided on the stage base 4309 and can be controlled independently. The position of the Y-axis base 4314 is detected at two positions opposite to each other by two linear encoders 4316 and 4321 disposed on the stage base 4309 adjacent to the linear motors 4318 and 4323. As a result, as with the X-axis, there is no deterioration in accuracy due to backlash or the like, and high-speed response is possible. Also, by detecting the position in the Y-axis direction by the linear encoders 4316 and 4321 at two positions on the opposite ends of the Y-axis base 4314, the minute rotation of the Y-axis base 4314 is detected and controlled by the difference between the detected values. can do. The minute rotation of the Y-axis base 4314 is a rotation around the Z-axis perpendicular to the X-axis and the Y-axis, and this is hereinafter referred to as a rotation θ around the Z-axis.

  In order to prevent radiant heat from the heater of the stage 4302 from being transmitted to the X-axis base 4306 and the Y-axis base 4314, a water cooling plate 4304 is provided between the trolley 4403 and the X-axis base 4306. . The X-axis base 4306 also has a built-in water cooling mechanism to prevent troubles such as linear bearings due to radiant heat from the heater of the stage 4302. Further, the coils of the linear motors that generate heat during the stage operation are cooled by an X-axis motor coil cooling plate 4411 and Y-axis motor coil cooling plates 4319 and 4324 provided in each linear motor. Further, with respect to the X-axis linear encoder 4310 and the Y-axis linear encoders 4316 and 4321, in order to prevent damage and accuracy deterioration due to thermal deformation, by providing an X-axis encoder cooling plate 4412 and Y-axis encoder cooling plates 4317 and 4322, respectively. The structure is maintained at a constant temperature.

  A cable guide 4413 corresponding to the X-axis linear encoder 4410 is provided to lead the detection signal cable from the moving X-axis linear encoder 4410 and the Y-axis linear encoders 4316 and 4321 to the fixed portion. Cable guides 4325 are provided corresponding to the linear encoders 4316 and 4321, respectively.

  With reference to FIGS. 31 and 32, an embodiment of a mask stage driving mechanism according to the present invention will be described. The stage structure will be described in order from the top. A base plate 4601 having a large circular opening at the center is fixed to a fixing portion (not shown). A cross roller bearing 4703 is attached to the edge of the opening of the base plate 4601. A θ-axis movable portion 4604 is provided on the lower surface side of the base plate 4601 via a cross roller bearing 4703 so as to be rotatable around the θ-axis, that is, the Z-axis. An opening corresponding to the opening of the base plate 4601 is also provided in the central portion of the θ-axis movable portion 4604. On the lower surface side of the θ-axis movable part 4604, a Y-axis movable part 4707 is attached so as to be movable in the Y-axis direction via a pair of Y-axis linear bearings 4706 extending in parallel with the Y-axis direction. An opening corresponding to the opening of the base plate 4601 is also provided at the center of the Y-axis movable portion 4707.

  The Y-axis movable part 4707 is provided with an X-axis movable part 4610 using a space formed to secure an installation space for the Y-axis linear bearing 4706. The X-axis movable portion 4610 is guided in the X-axis direction by a lift air bearing 4611 and yaw guide air bearings 4615 and 4616. An opening corresponding to the opening of the base plate 4601 is also provided in the central portion of the X-axis movable portion 4610.

  More specifically, the X-axis movable unit 4610 is between the θ-axis movable unit 4604 and the Y-axis movable unit 4707 and is provided on a plurality of surfaces provided on the surface of the Y-axis movable unit 4707 facing the X-axis movable unit 4610. It is configured to be movable in the X-axis direction via a lift air bearing 4611. The lift air bearing 4611 is for levitation of the X-axis movable part 4610 by blowing compressed air onto the lower surface of the X-axis movable part 4610. Here, an angle of 120 degrees with respect to the center of the X-axis movable part 4610 Three are provided at intervals.

  Further, the X-axis movable portion 4610 is made of a magnetic material, and suction magnets 4618 are arranged at a plurality of locations on the surface of the Y-axis movable portion 4707 facing the X-axis movable portion 4610. In particular, nine magnets 4618 are arranged around the lift air bearing 4611, three in total. Further, the X-axis movable part 4610 has two end edges parallel to the X-axis direction, and these two edge parts are respectively provided by yaw guide air bearings 4615 and 4616 provided on the Y-axis movable part 4707. It is configured to guide movement in the X-axis direction. Two yaw guide air bearings 4615 and 4616 are provided for each edge of the X-axis movable portion 4610. In addition, two yaw guide air bearings 4616 provided on one end edge side of the X-axis movable portion 4610 are combined with a preloading piston 4620, respectively, with respect to the one end edge portion. Preload is applied. A mask stage 4730 is combined with the X-axis movable portion 4610 via a boss 4710-1. The mask stage 4730 has an opening slightly smaller than the opening of the base plate 4601 at the center, and protrudes from the lower surface side of the Y-axis movable part 4707, and has a holding part for the mask 4714 at its lower end.

  With the above configuration, a three-degree-of-freedom mask stage of the X axis, the Y axis, and the θ axis is configured. The output shaft of the θ-axis drive motor 4605 moves in the axial direction according to the rotation of the θ-axis drive motor 4605 and pushes the θ-axis drive plate 4619. As a result, the θ-axis movable portion 4604 rotates counterclockwise around the Z axis with respect to its center. Note that the output shaft of the θ-axis drive motor 4605 is not fixed to the drive plate 4619. For this reason, a tension spring 4617 is provided between the base plate 4601 and the θ-axis movable portion 4604 to apply clockwise preload, thereby preventing backlash and rotation failure due to friction of the cross roller bearing 4703. It is out. The rotation angle of the θ-axis movable unit 4604 is measured by a hollow rotary encoder 4702 that is attached to the θ-axis movable unit 4604 and combined with a rotation shaft 4704-1 that rotates integrally, and ensures accuracy.

  The Y-axis movable unit 4707 is driven in the Y-axis direction by a Y-axis linear motor 4608 disposed between the end of the θ-axis movable unit 4604 and the end of the Y-axis movable unit 4707. The position of the Y-axis movable unit 4707 is measured by a Y-axis linear encoder 4709 disposed in the vicinity of the Y-axis linear motor 4608. X-axis movable portion 4610 is driven by X-axis linear motor 4713. The X-axis linear motor 4713 is disposed on the lower surface side of the Y-axis movable part 4707, and the movable part is connected to the boss 4710-1, so that the X-axis movable part 4610 and the boss 4710-1 are connected to the X-axis linear motor 4713. Driven in the axial direction. The position of the X-axis movable unit 4610 is measured by an X-axis linear encoder 4612 disposed between the lower surface side of the Y-axis movable unit 4707 and the boss 4710-1.

  Details of the guide mechanism of the X-axis movable unit 4610 will be described. The X-axis movable portion 4610 has high trajectory tracking performance in order to perform scanning that moves at a constant speed while irradiating a workpiece (not shown) disposed below the mask 4714 with a laser beam using the central opening as an optical path. Positioning accuracy is required. Therefore, a static pressure bearing is employed for the guide mechanism of the X-axis movable portion 4610. The configuration of the guide mechanism of the X-axis movable unit 4610 includes two guide mechanisms in the vertical direction (radial) and the horizontal direction. The hydrostatic bearing for vertical guidance is composed of a lift air bearing 4611 attached to the Y-axis movable part 4707 and a guide surface of the X-axis movable part 4610. In particular, in order to maintain a gap (about 5 to 10 μm) in which high guide rigidity is obtained, a preload is applied by the attractive forces of a plurality of magnets 4618 attached to the Y-axis movable portion 4707.

  Normally, the air bearing is fixed to the movable part side, but taking advantage of the short stroke required for the X-axis movable part 4610, the lift air bearing 4611 is not the X-axis movable part 4610 but the base of the X-axis movable part 4610. It is configured to be fixed to the Y axis movable portion 4707 side. As a result, the weight of the X-axis movable portion 4610 is reduced, and the number of air supply tubes connected to the air bearing, which becomes a disturbance during movement, is reduced.

  The static pressure bearing for lateral guidance of the X-axis movable part 4610 is configured by sandwiching the X-axis movable part 4610 by two sets of yaw guide air bearings 4615 and 4616 attached to the X-axis movable part 4610. The two yaw guide air bearings 4615 are each supported by an adjusting bolt 4621. The adjustment bolt 4621 is attached to the X-axis movable part 4610, and the tip thereof is in contact with the yaw guide air bearing 4615. By adjusting the amount of the adjustment bolt 4621, the lateral posture of the X-axis movable part 4610 is adjusted. be able to.

  A yaw guide air bearing 4616 attached to the side opposite to the yaw guide air bearing 4615 is supported by a preload piston 4620 and supported by a constant force. For this reason, a constant hydrostatic bearing clearance can be maintained without being affected by thermal deformation, machining accuracy, assembly errors, etc. of the X-axis movable part 4610 and the Y-axis movable part 4707. Yes.

  The support points of all air bearings are spherically supported by ceramic balls, so that they can absorb to some extent even if the parallelism between the air bearing surface and the mating surface is lost, such as swell or thermal deformation of the mating surface. .

  33 and 34 are schematic views of a vacuum chamber stage device provided with a pneumatic tilt mechanism according to the present invention. The stage apparatus is installed in a vacuum chamber that can obtain a vacuum or a reduced pressure state, but the vacuum chamber is not shown here.

  The pneumatic tilt mechanism according to the present invention has a structure in which three bellow cylinders 5104-1, 5104-2, 5104-3 and a plate spring 5103 of a pneumatic drive type are arranged on a base 5102 and a stage 5201 is supported by these. It has become. The leaf spring 5103 has a cross shape, and the central portion (intersection) of the leaf spring 5103 is fixed to a base portion provided on the lower surface of the stage 5201 with a bolt or the like. Further, the four end portions of the leaf spring 5103 are fixed to the base 2 side via the support bases 5202-1.

  The bellows cylinders 5104-1 to 5104-3 are formed by sealing a pneumatic cylinder with a bellows, and are configured so that leaked air does not flow into the vacuum chamber even if air leaks from the pneumatic cylinder.

  This pneumatic tilt mechanism supports the stage 5201 by a leaf spring 5103, and expands and contracts the bellows cylinders 5104-1 to 5104-3 by sending compressed air to the bellows cylinders 5104-1 to 5104-3. Adjust the height and tilt.

  FIG. 35 is a diagram illustrating the configuration of the irradiation optical system 5420. A homogenizer 5421 to which laser light AL from a laser light source (not shown) is incident includes first to fourth cylindrical lens arrays CA1 to CA4 for independently controlling vertical and horizontal beam sizes, and condenser lenses for condensing light. 5521a. Here, the first and third cylindrical lens arrays CA1, CA3 have a curvature in a cross section parallel to the paper surface, and the second and fourth cylindrical lens arrays CA2, CA4 have a curvature in a cross section perpendicular to the paper surface.

  Laser light AL from the homogenizer 5421 enters the mask assembly 5422 through the turn mirror 5525. This mask assembly 5422 is illuminated with a laser beam AL and has a mask 5522a in which a pattern to be irradiated on the workpiece W is formed on the lower surface 5580, and a laser beam AL around the light transmitting portion (ie, opening) of the pattern of the mask 5522a. Is made up of a reflection member 5522b that prevents the incident light from entering and causing return light, and a field lens 5522c that adjusts the pupil position. Here, the reflecting member 5522b is disposed to be inclined with respect to the mask 5522a, and the reflected light RL from the upper surface 5581 of the reflecting member 5522b is emitted in a direction deviating from the optical axis OA, and passes through the field lens 5522c to be a beam damper. 5526 is incident. Note that the field lens 5522c can also be considered part of the homogenizer 5421.

  The laser light AL that has passed through the mask 5522a enters the projection lens 5423. The projection lens 5423 reduces-projects, that is, forms and transfers, a slit image, which is a light transmission pattern formed on the mask 5522a illuminated by the laser light AL, onto the processing surface of the workpiece W.

  Next, a first embodiment of the CVD apparatus according to the present invention will be described with reference to FIGS. In FIG. 36, this CVD apparatus preferably uses silane as a material gas, and forms a silicon oxide film as a gate insulating film on the upper surface of a normal TFT glass substrate 7111. A container 7112 of the CVD apparatus is a vacuum container whose inside is maintained in a desired vacuum state by an exhaust mechanism 7113 when performing a film forming process. The exhaust mechanism 7113 is connected to an exhaust port 7112 b-1 formed in the vacuum vessel 7112.

  Inside the vacuum vessel 7112 is provided a partition wall portion 7114 made of a conductive member in a substantially horizontal state at an intermediate position in the vertical direction, and the peripheral portion of the partition wall portion 7114 having a square shape, for example, is a vacuum container. 7112 is disposed so as to contact the peripheral wall portion of 7112. The inside of the vacuum vessel 7112 is isolated into two upper and lower chambers by a partition wall portion 7114. The upper chamber forms a plasma generation space 7115, and the lower chamber forms a film formation processing space 7116. The partition wall portion 7114 has a desired specific thickness, has a flat plate shape as a whole, and has a planar shape similar to the horizontal sectional shape of the vacuum vessel 7112. An internal space 7124 is formed in the partition wall portion 7114.

  The glass substrate 7111 is disposed on a substrate holding mechanism 7117 provided in the film formation processing space 7116. The glass substrate 7111 is substantially parallel to the partition wall portion 7114 and is disposed so that the film formation surface (upper surface) faces the lower surface of the partition wall portion 7114. The potential of the substrate holding mechanism 7117 is held at the ground potential which is the same potential as the vacuum vessel 7112. Further, a heater 7118 is provided inside the substrate holding mechanism 7117. The temperature of the glass substrate 7111 is maintained at a predetermined temperature by the heater 7118.

  The structure of the vacuum vessel 7112 will be described. The vacuum container 7112 includes an upper container 7112a that forms a plasma generation space 7115 and a lower container 7112b that forms a film formation processing space 7116 from the viewpoint of improving its assemblability. When the upper container 7112a and the lower container 7112b are combined to form the vacuum container 7112, a partition wall portion 7114 is provided between the two. The partition wall 7114 has a peripheral edge in contact with the lower insulating member 7122 of the annular insulating members 7121 and 7122 interposed between the upper container 7112a when the electrode 7120 is provided as described later. It is attached. As a result, an isolated plasma generation space 7115 and film formation processing space 7116 are formed above and below the partition wall portion 7114. A plasma generation space 7115 is formed by the partition wall portion 7114 and the upper container 7112a. A region where the plasma 7119 is generated in the plasma generation space 7115 is formed by a plate-like electrode (high-frequency electrode) 7120 disposed at a substantially central position between the partition wall 7114 and the upper container 7112a. The electrode 7120 has a plurality of holes 7120a. The partition wall 7114 and the electrode 7120 are supported and fixed by two annular insulating members 7121 and 7122 provided along the inner side surface of the upper container 7112a. The annular insulating member 7121 is provided with an introduction pipe 7123 for introducing oxygen gas into the plasma generation space 7115 from the outside. The introduction pipe 7123 is connected to an oxygen gas supply source (not shown) via a mass flow controller (not shown) that controls the flow rate.

  The inside of the vacuum vessel 7112 is isolated by the partition wall portion 7114 into the plasma generation space 7115 and the film formation processing space 7116, and a plurality of through holes 7125 satisfying a predetermined condition pass through the internal space 7124 in the partition wall portion 7114. The plasma generation space 7115 and the film formation processing space 7116 are connected only through these through holes 7125. An internal space 7124 formed in the partition wall portion 7114 is a space for dispersing the material gas and supplying it uniformly to the film formation processing space 7116. Further, a plurality of diffusion holes 7126 for supplying a material gas to the film formation processing space 7116 are formed in the lower wall of the partition wall portion 7114. The through hole 7125 or the diffusion hole 7126 is formed so as to satisfy a predetermined condition described later. The internal space 7124 is connected to an introduction pipe 7128 for introducing a material gas. The introduction pipe 7128 is arranged so as to be connected from the side. Further, in the internal space 7124, a uniform plate 7127 pierced so as to have a plurality of holes 7127 a is provided substantially horizontally so that the material gas is uniformly supplied from the diffusion holes 7126. As shown in FIG. 37, the internal space 7124 of the partition wall portion 7114 is divided into two upper and lower spaces 7124a and 7124b by the uniform plate 7127. The material gas introduced into the internal space 7124 by the introduction pipe 7128 is introduced into the upper space 7124a, reaches the lower space 7124b through the hole 7127a of the uniform plate 7127, and further passes through the diffusion hole 7126 to form a film formation process. It will be diffused into the space 7116. Based on the above structure, the material gas can be supplied uniformly over the entire film formation processing space 7116.

  In FIG. 37, a part of the partition wall portion 7114 is shown enlarged, and the main portions of the through hole 7125, the diffusion hole 7126, and the uniform plate 7127 are shown enlarged. As an example, the through hole 7125 has a large diameter on the plasma generation space 7115 side and is narrowed on the film formation processing space 7116 side, and is formed with a small diameter.

  A power introduction rod 7129 connected to the electrode 7120 is provided on the ceiling of the upper container 7112a. The discharge high frequency power is supplied to the electrode 7120 by the power introduction rod 7129. The electrode 7120 functions as a high frequency electrode. The power introduction rod 7129 is covered with an insulator 7131 so as to be insulated from other metal parts.

A film forming method using the CVD apparatus configured as described above will be described. A glass substrate 7111 is carried into the vacuum container 7112 by a transfer robot (not shown) and placed on the substrate holding mechanism 7117. The inside of the vacuum vessel 7112 is evacuated by an exhaust mechanism 7113, decompressed, and maintained in a predetermined vacuum state. Next, oxygen gas is introduced into the plasma generation space 7115 of the vacuum vessel 7112 through the introduction pipe 7123. At this time, the flow rate of oxygen gas is controlled by an external mass flow controller. Using equations (1) and (2), the flow rate (u) of oxygen is obtained from the flow rate (Q _O2 ) of oxygen gas, the pressure (P _O2 ), and the temperature (T).

Q _O2 = ρ _O2 uA Formula (1)
P _O2 = (ρ _O2 RT) / M Formula (2)
On the other hand, silane which is a material gas is introduced into the internal space 7124 of the partition wall portion 7114 through the introduction pipe 7128. Silane is first introduced into the upper space 7124a of the inner space 7124, homogenized by the uniform plate 7127 and moved to the lower portion 7124b, and then directly through the diffusion hole 7126 to the film forming treatment space 7116, that is, It is introduced without contacting the plasma. The substrate holding mechanism 7117 provided in the film formation processing space 7116 is held at a predetermined temperature in advance because the heater 7118 is energized.

  In the above state, high frequency power is supplied to the electrode 7120 via the power introduction rod 7129. Discharge occurs due to the high frequency power, and oxygen plasma 7119 is generated around the electrode 7120 in the plasma generation space 7115. By generating the oxygen plasma 7119, radicals (excited active species) that are neutral excited species are generated.

  When film formation is performed on the surface of the substrate 7111, the internal space of the vacuum vessel 7112 is separated from the plasma generation space 7115 and the film formation processing space 7116 by a partition wall portion 7114 formed of a conductive material. Then, oxygen gas is introduced and high-frequency power is supplied to the electrode 7120 to generate oxygen plasma 7119. On the other hand, in the film forming treatment space 7116, silane which is a material gas passes through the internal space 7124 and the diffusion hole 7126 of the partition wall portion 7114. Introduced directly. Radicals in the oxygen plasma 7119 generated in the plasma generation space 7115 are introduced into the film formation processing space 7116 through the plurality of through holes 7125 in the partition wall portion 7114, and silane is introduced into the internal space 7124 and the diffusion holes in the partition wall portion 7114. The film is introduced directly into the film formation processing space 7116 through 7126. In addition, silane introduced directly into the film formation processing space 7116 is prevented from back-diffusion to the plasma generation space side based on the form of the through holes 7125. In this manner, when silane, which is a material gas, is introduced into the film formation treatment space 7116, the silane does not directly contact the oxygen plasma 7119, and the silane and oxygen plasma are prevented from reacting violently. Thus, a silicon oxide film is formed on the surface of the substrate 7111 arranged to face the lower surface of the partition wall portion 7114 in the film formation processing space 7116.

  In the above structure, the size and the like of the plurality of through holes 7125 of the partition wall portion 7114 are such that the oxygen gas in the plasma generation space 7115 is a mass transfer flow in the through holes, and the silane in the film formation processing space 7116 is the through holes. When it is assumed that the diffusion movement is performed to the opposite space through 7125, the movement amount is determined to be limited to a desired range. That is, for example, with respect to oxygen gas and silane flowing through the through-hole 7125 of the partition wall portion 7114 at the temperature T, the mutual gas diffusion coefficient is D, and the length of the minimum diameter portion of the through-hole 7125 (characteristic length of the through-hole) When L is L, a gas flow rate (assuming a gas flow rate u) is used so that the relationship of uL / D> 1 is satisfied. The above conditions regarding the form of the through hole are preferably similarly applied to the diffusion hole 7126 formed in the partition wall portion 7114.

The relationship of uL / D> 1 is derived as follows. For example, the following equation (3) is established using the silane gas density (ρ _SiH4 ), the diffusion flow rate (u _SiH4 ), and the mutual gas diffusion coefficient (D _SiH4-O2 ) regarding the relationship between oxygen and silane moving through the through-hole 7125. When the characteristic length of the through hole is L, Expression (3) can be approximated to Expression (4). As a result of comparing both sides of the formula (4), the diffusion flow rate (u _SiH4 ) of silane is represented by -D _SiH4-O2 / L. Therefore, when the oxygen flow rate obtained from the above equations (1) and (2) is u and the diffusion flow rate of silane is -D _SiH4-O2 / L, the ratio of the absolute values of these two flow rates, that is, | -U / (-D _SiH4-O2 / L) | = uL / D _SiH4-O2 is the ratio of oxygen mass transfer rate to silane diffusion rate, and this ratio uL / D _{SiH4-O2 is set} to 1 or more. This means that the flow rate by convection is larger than the flow rate of diffusion. That is, setting the value of uL / D _SiH4-O2 to 1 or more means that the diffusion effect of silane is small.

_{ρ SiH4 u SiH4 = -D SiH4-} O2 gradρ SiH4 (3)
ρ _SiH4 u _SiH4 ≒ -D _SiH4-O2 ρ _SiH4 / L (4)
Next, a specific example will be described. The temperature of the partition wall portion 7114 is 300 ° C., the diameter of the through hole 7125 formed in the partition wall portion 7114 is 0.5 mm, the length (L) of the 0.5 mm diameter portion is 3 mm, and the total number of the through holes 25 is 500 pieces. When the gas flow rate of oxygen gas is 500 sccm and the pressure of the film forming treatment space 7116 is 100 Pa, the value of the above equation (4) is 11. In such a case, since the influence of the flow is sufficiently large compared to the diffusion of silane gas, the diffusion of silane gas into the plasma generation space 7115 is reduced.

  As described above, the plasma generation space 7115 and the film formation processing space 7116 are separated and separated so as to be chambers closed by the partition wall portion 7114 in which a large number of through holes 7125 and diffusion holes 7126 having the above characteristics are formed. Therefore, there is almost no contact between the silane directly introduced into the film formation processing space 7116 and the oxygen plasma. Therefore, as in the conventional apparatus, the silane and oxygen plasma are prevented from reacting violently.

  Next, a second embodiment of the CVD apparatus according to the present invention will be described with reference to FIG. In FIG. 38, elements substantially the same as those described in FIG. 36 are denoted by the same reference numerals, and description thereof will not be repeated here. The characteristic configuration of this embodiment is such that a plate-like insulating member 7333 is provided on the inner side of the ceiling portion of the upper container 7112a, and the electrode 7120 is arranged on the lower side thereof. The hole 7120a is not formed in the electrode 7120, but has a form of a single plate. A plasma generation space 7115 having a parallel plate electrode structure is formed by the electrode 7120 and the partition wall portion 7114. Other configurations are substantially the same as those of the first embodiment. Furthermore, the operations and effects of the CVD apparatus according to the second embodiment are the same as those in the first embodiment.

Next, a third embodiment of the CVD apparatus according to the present invention will be described with reference to FIG. In FIG. 39, elements substantially the same as those described in FIG. 36 are denoted by the same reference numerals, and the detailed description thereof is not repeated here. The characteristic configuration of this embodiment is that a second gas introduction pipe 7423 for introducing a cleaning gas from the outside to the plasma generation space 7115 is added to the annular insulating member 7122 provided inside the side wall portion of the upper container 7112a. Is provided. The introduction pipe 7423 is connected to a cleaning gas supply source (not shown) via a mass flow controller (not shown) that controls the flow rate. When a cleaning gas is introduced into the plasma generation space 7115 through the second gas introduction pipe 7423 and high-frequency power is supplied from the high-frequency power source to the electrode 7120, the plasma generation space 7115 has a film surface on the substrate 7111 for cleaning. A plasma is generated to make the radicals used. For example, NF ₃ , ClF ₃ , C ₂ F ₄ , C ₂ F ₆ , H ₂ , O ₂ , N ₂ , F ₂ , Ar, etc. (rare gas, halogenated gas) are used as the cleaning gas. Other configurations are substantially the same as those of the first embodiment.

  Use of the gas introduction pipe 7123 and the second gas supply pipe 7423 is controlled to be executed alternatively. In this embodiment, the cleaning gas is first introduced to clean the surface of the film on the substrate 7111, and then the deposition gas is introduced to form a gate insulating film on the surface of the film on the substrate 7111. Is done.

  That is, after a substrate 7111 having a laser-annealed film (polysilicon film) formed thereon is mounted on the substrate holder 7117, a cleaning gas is introduced into the plasma generation space 7115 from the second gas introduction pipe 7423. The high frequency power is supplied to the electrode 7120 through the power introducing rod 7129. As a result, discharge is started in the plasma generation space 7115 and a cleaning gas plasma 7419 is generated. As a result, radicals are generated in the plasma, the radicals move to the film formation treatment space 7116 through the plurality of through holes 7125 of the partition wall portion 7114, and the surface of the film formed over the substrate 7111 is cleaned with the radicals. Thereby, impurities generated on the film surface of the substrate after laser annealing can be removed.

  After the above substrate cleaning process is completed and a predetermined condition is satisfied, oxygen gas is introduced into the plasma generation space 7115 from the gas supply pipe 7123, and high frequency power is supplied to the electrode 7120 via the power introduction rod 7129. The As a result, discharge is started in the plasma generation space 7115 and oxygen plasma 7119 is generated. As a result, radicals are generated in the plasma, and the radicals move to the film formation treatment space 7116 through the plurality of through holes 7125 of the partition wall portion 7114. On the other hand, along with the introduction of radicals, the material gas is introduced from the introduction pipe 7128 through the partition wall portion 7114 into the film forming treatment space 7116. In the film formation processing space 7116, radicals react with the material gas, and as a result, a gate insulating film is formed on the surface of the film formed on the substrate 7111.

  In addition, it is preferable that the film-forming apparatus which concerns on this invention is comprised by consistent vacuum.

  Next, a film forming method using the apparatus of the embodiment of the present invention will be described.

  FIG. 40 shows an example of a film forming apparatus according to the present invention. In FIG. 40, reference numeral 7112 denotes the vacuum container of FIG. As described above, the vacuum vessel 7112 includes the plasma generation space 7115 and the film formation processing space 7116 which are separated from each other by the partition wall portion 7114 having a large number of through holes.

In FIG. 40, reference numeral 7512 denotes a film forming material gas supply device. A material gas supplied from the film forming material gas supply device 7512 is introduced into the internal space 7124 in the partition wall portion 7114 via a gas introduction path 7513 including an MFC (mass flow controller: flow rate controller) 7513a. As the material gas, a silicon hydride compound such as SiH ₄ (Si _n H _{2n + 2} (n = 1, 2, 3,...)) Is used. In the film formation treatment space 7116, the material gas introduced through the internal space 7124 of the partition wall portion 7114 reacts with the radicals introduced through a large number of through holes 7125 formed in the partition wall portion 7114, so that the material gas is decomposed. Then, a silicon oxide thin film is deposited on the substrate carried into the film formation chamber, and film formation is performed.

  Reference numeral 7514 denotes a host controller. The host controller 7514 has a function of controlling the flow rate of the material gas in the MFC 7513a provided in the gas introduction path 7513. The controller 7514 controls the flow rate of the material gas in the MFC 7513a, so that the supply amount of the material gas introduced into the film formation processing space 7116 can be controlled to a desired value as described later. In the graph shown in FIG. 41, the horizontal axis represents time (t), the vertical axis represents the flow rate of material gas (sccm), and an example of a change in the material gas flow rate is illustrated. In this embodiment, the flow rate of the material gas in the MFC 7513a is controlled based on the controller 7514, and the introduction flow rate (supply amount) of the material gas to the film formation processing space 7116 is limited at the start of discharge at the initial stage of film formation. Then, it has the feature to increase. Next, a method for limiting the introduction flow rate of the material gas will be described.

FIG. 42 shows an example of control of the supply amount of SiH ₄ which is a material gas, the horizontal axis is time, and the vertical axis is the introduction flow rate. On the time axis, times t ₀ , t ₁ and t ₂ are set. For example, oxygen (O ₂ ) is used as the plasma generating gas. Time t ₀ is a time when oxygen gas is introduced into the plasma generation chamber and discharge of the oxygen gas is started, and is a start time of film formation. At the time _{t 1,} the supply of SiH ₄ is started. Therefore, SiH ₄ is not supplied from time t ₀ to time t ₁ . In between time _{t 1} of time _{t 2, the} supply amount of SiH ₄ at gradually increasing time _{t 2} in accordance with the supply amount of SiH ₄ is time to reach a constant value. Time _{t 2} after the supply amount of SiH ₄ is kept at a constant value. As described above, at the initial stage of film formation including the start of discharge (time close to t _{0 to} t ₁ and t ₁ ), the supply amount of the material gas is limited to form a silicon-excess silicon oxide thin film at the initial stage of film formation. In addition, since the supply amount of the material gas is gradually increased thereafter, the film formation time is shortened and the practicality is improved.

Further, the control may be performed so that the increase in the supply amount at t _{1 to} t ₂ is changed by a step function or various functions such as a proportional function, a linear function, a quadratic function, and an exponential function.

  In each of the above-described embodiments, the example of silane was described as the material gas. However, the present invention is not limited to this, and other material gases such as TEOS can be used. Further, it can be applied not only to a silicon oxide film but also to other film formation such as a silicon nitride film. The principle idea of the present invention is applicable to all processes in which particles are generated by contact of a material gas with plasma and ions are incident on a substrate, such as film formation, surface treatment, isotropic etching, etc. It can be applied to. Furthermore, in the above-described embodiment, the partition wall portion has a double structure, but it is of course possible to have a multilayer structure as necessary.

  As apparent from the above description, according to the present invention, when a silicon oxide film or the like is formed on a large-area substrate by using a material gas such as silane by plasma CVD, a plurality of through holes or diffusions satisfying a predetermined condition are formed. By providing a partition wall with holes, the inside of the vacuum vessel is separated into a plasma generation space and a film formation processing space, and active species generated in the plasma generation space are introduced into the film formation processing space through the through holes in the partition wall. Since the material gas is introduced directly into the film forming treatment space without touching the plasma through the internal space of the partition wall and the diffusion hole, the intense chemical reaction between the material gas and the plasma can be prevented. Generation of particles can be suppressed and ion incidence to the substrate can be prevented.

  In addition, the material gas can be introduced uniformly, and oxygen gas radicals can be uniformly supplied to the film formation processing space through the plurality of through holes formed in the partition wall, thereby distributing radicals and silane in the vicinity of the surface of the substrate. And film formation on a large-area substrate can be performed effectively.

  FIG. 43 is a cross-sectional view of a cluster tool type device as viewed from the side. This apparatus has a deposition chamber 8101 for forming a silicon oxide film to be a gate insulating film on the surface of a substrate 8109, a load lock chamber 8102, and a transfer chamber 8103 having a transfer robot 8130 as a transfer mechanism inside. is doing.

  The film formation chamber 8101 includes a CVD unit 8113 inside. A plasma is generated in the CVD unit 8113, and a silicon oxide film is formed by utilizing active species taken out from the plasma. The major feature of the apparatus of this embodiment is the configuration of the transfer chamber 8103. As shown in FIG. 43, the transfer chamber 8103 has a gas introduction system (hereinafter referred to as a pressure-regulating gas introduction system) that introduces a gas that does not adversely affect film formation in the film formation chamber 8101 in order to adjust the internal pressure. ) 8132. In the present embodiment, the pressure adjusting gas introduction system 8132 introduces hydrogen gas. The pressure adjusting gas introduction system 8132 includes a flow regulator and a filter (not shown) so that a high-pressure pressure adjusting gas can be introduced at a predetermined flow rate.

  Note that “a gas that does not adversely affect film formation” means a gas that does not adversely affect the quality of the thin film to be produced. This gas includes a gas that is not directly involved in film formation, such as hydrogen, and a gas that has an effect of improving the film quality.

  The fact that the transfer chamber 8103 includes the pressure-adjusting gas introduction system 8132 is related to a specific technical idea regarding the exhaust system 8131 of the transfer chamber 8103. That is, the apparatus according to the present embodiment is configured to maintain the pressure in the transfer chamber 8103 so that the pressure is slightly lower than the pressure in the film forming chamber 8101.

  Since the exhaust system 8131 of the transfer chamber 8103 only needs to be exhausted to a relatively high pressure in this way, it has a low-cost configuration. For the exhaust system 8131 of the transfer chamber 8103, for example, a combination of an inexpensive dry pump and a mechanical booster pump can be employed.

  As the exhaust system 8131 of the transfer chamber 8103, an exhaust system having a higher exhaust speed than that of the film formation chamber 8101 is usually used, and the transfer chamber 8103 is exhausted to a pressure lower than that of the film formation chamber 8101. However, with such a configuration, as described above, the configuration of the exhaust system 8131 becomes expensive. For example, in order to obtain the ultimate pressure in the film formation chamber 8101 described above, it is necessary to use a very expensive vacuum pump such as a turbo molecular pump. A combination of an inexpensive dry pump and mechanical booster pump is sufficient if the ultimate pressure is 1 Pa or higher, but if the ultimate pressure is lower than 1 Pa, a turbo molecular pump that is several times more expensive than this is required.

  In addition, since the pressure in the transfer chamber 8103 is set to be relatively high, the exhaust operation at the start of operation of the apparatus can be completed in a short time. Therefore, the production efficiency of the entire apparatus is increased.

  Another major feature of the apparatus of this embodiment is that a modified species supply unit 8133 that supplies chemical species having a modifying action on the surface of the substrate 8109 (hereinafter referred to as modified species) is provided in the transfer chamber 8103. It is a point. This point will be described below.

  The reformed species supply unit 8133 is configured to form plasma by applying energy to the gas introduced by the reforming gas introduction system 8134. The configuration of the reformed species supply unit 8133 will be described with reference to FIG. FIG. 44 is a schematic side sectional view showing the structure of the reforming species supply unit 8133 provided in the transfer chamber 8103 of the apparatus shown in FIG.

  The reformed species supply unit 8133 has basically the same configuration as that shown in FIG. However, there is no configuration for introducing the material gas, and the partition wall portion 7114 has a plate shape with a plurality of holes. As shown in FIG. 43, the modified species supply unit 8133 is disposed in the transfer chamber 8103 at a position close to the gate valve 8104c at the boundary with the film forming chamber 8101-, and on the transfer line of the substrate 8109. Located on the upper side.

  The reforming gas introduction system 8134 supplies hydrogen gas to the plasma generation space in the same manner as the pressure adjustment gas introduction system 8132. The piping of the pressure regulating gas introduction system 8132 may be branched and connected to the reforming species supply unit 8133 so that the pressure regulating gas introduction system 8132 is also used as the reforming gas introduction system 8134.

  When the high-frequency power supply operates in a state where hydrogen gas is introduced into the plasma generation space by the reforming gas introduction system 8134, plasma is formed and hydrogen active species flow downward. This hydrogen active species corresponds to a reformed species in this embodiment, and reforming is performed by supplying this to the surface of the substrate. For example, if the surface of the substrate 8109 is oxidized, it is reduced. In addition, when a bond end is present on the surface, the hydrogen active species terminates this and chemically stabilizes the surface state. At the time of this modification, the substrate 8109 may be stopped on the transfer line, or may be performed while being moved for efficiency.

  The major feature of the device of the second embodiment is that a laser annealing process and a gate insulating film forming process necessary for manufacturing a TFT-LCD using a polysilicon film as a channel layer can be continuously performed in a vacuum. It is that. Also in the apparatus of the second embodiment, the transfer chamber 8103 is provided with a pressure adjusting gas introduction system 8132, and the pressure in the transfer chamber 8103 is higher than 1 Pa but lower than the film forming chamber-8101 although it is a vacuum pressure. To be maintained. Similarly, the pressure adjusting gas introduction system 8132 introduces hydrogen gas into the transfer chamber 8103.

  According to the second embodiment, the structure in which the surface of the substrate 8109 is modified by supplying the modified species after the annealing step is extremely important in improving the operating characteristics of the TFT. Yes. Silicon dangling bonds exist on the surface of the polysilicon film obtained by crystallizing the amorphous silicon film in the annealing process. Therefore, when the substrate 8109 is transferred from the annealing chamber (not shown) to the film forming chamber 8101, if there is a gas that easily reacts with silicon such as oxygen in the atmosphere, the silicon can be easily formed at the unbonded end. Reacts with the surface of the polysilicon film to create a contaminated region. If such a fouling region is present at the interface between the polysilicon film and the gate insulating film, a stoichiometric composition cannot be obtained, and problems such as the generation of defect levels that hinder the operating characteristics of the TFT are likely to occur. .

  In the present embodiment, after the annealing step, the surface is modified with hydrogen active species, and the unbonded ends of silicon are terminated with hydrogen, so the above-described problems are suppressed. Furthermore, although the transfer chamber 8103 is a vacuum with a relatively high pressure, it is purged with hydrogen gas, so that even if there is an unbonded end, the possibility that a pollutant reacts with it is reduced, and it reacts with hydrogen. Similarly, there is a high possibility that the termination will be stable. For this reason, according to the apparatus of this embodiment, the interface state between the polysilicon film and the gate insulating film, which is a very important technical matter in manufacturing the polysilicon TFT, can be made extremely high quality.

  In addition, the point that the modified species supply unit supplies the active species has an important significance in connection with the modification after the annealing step. As described above, in addition to the active species, ion incidence may be used for the modification of the surface of the substrate 8109. However, the use of ion incidence for modification after the annealing step creates problems. The polysilicon film crystallized by the annealing process has a relatively weak crystal structure. Therefore, when ions are incident, the bonds are easily broken, and irregularities with the rough surface of the polysilicon film are formed. As a result, there may be a problem that the interface characteristics are hindered or the channel resistance is increased.

  In the present embodiment, the CVD unit 8113 is used to supply active species by forming plasma in a region away from the surface of the substrate. Accordingly, there is essentially no incidence of ions on the surface of the substrate, and the above-described problem does not occur.

  FIG. 45 is a diagram for explaining the structure of a laser annealing apparatus according to the present invention.

  This laser annealing apparatus includes a stage 3210 on which a workpiece W, which is a glass plate on which a semiconductor thin film such as amorphous Si is formed, can be moved smoothly in three dimensions, and a pair of laser beams having different characteristics. A pair of laser light sources 3221 and 3222 for generating LB1 and LB2 respectively, a combining optical system 3230 for combining these laser beams LB1 and LB2, and a combined beam CL combined by the combining optical system 3230 are used as a linear beam AB. An irradiation optical system 3240 that is incident on the workpiece W at a predetermined illuminance, and a scanning unit that moves the mask 3242 provided in the irradiation optical system 3240 and scans the linear beam AB projected on the workpiece W on the workpiece W. A certain mask driving device 3250 and a stage 3210 on which the workpiece W is placed are necessary for the irradiation optical system 3240 and the like. It comprises a stage driving unit 3260 for moving properly, and a main control unit 32100 which performs overall control of the laser annealing apparatus overall operation of each section.

  The pair of laser light sources 3221 and 3222 are both an excimer laser and other pulse light sources for heating the semiconductor thin film on the workpiece W, and a pair of laser beams LB1 having different characteristics such as emission time, peak intensity, or wavelength, LB2 is generated individually.

  The combining optical system 3230 is for spatially joining a pair of laser beams LB1 and LB2 from both laser light sources 3221 and 3222 to form a combined light CL, and a pair of knife edge mirrors 3231 arranged in parallel. , 3232. A divergence optical system 3271 and a telescope optical system 3272 are provided as adjusting devices between the combining optical system 3230 and the laser light sources 3221 and 3222, respectively. The divergence optical system 3271 has a role as an adjustment optical system for finely adjusting the optical axis direction imaging position (beam forming position) by the homogenizer 3241 provided in the irradiation optical system 3240 for the first beam LB1 from the laser light source 3221. . The telescope optical system 3272 serves as an afocal optical system that adjusts the beam size of the second beam LB2 from the laser light source 3222 to match the beam size of the first beam LB1 incident on the combining optical system 3230. Have.

  The irradiation optical system 3240 divides the combined light CL from the combining optical system 3230 into a plurality of parts, and converts the divided light into a rectangular beam so as to be uniformly incident on a predetermined surface, and a slit-like light A mask 3242 that has a transmission pattern and is disposed on a predetermined surface and blocks the synthesized light CL, and a projection lens 3243 that projects the transmission pattern formed on the mask 3242 on the workpiece W as a linear beam AB.

  The stage driving device 3260 performs alignment for driving the stage 3210 and aligning a predetermined area on the workpiece W with the irradiation optical system 3240. Further, the stage driving device 3260 moves the mask 3242 to an area adjacent to the predetermined area when the mask driving apparatus 3250 scans the linear beam AB in the predetermined area on the workpiece W and laser annealing of the predetermined area is completed. Align the step by step. Note that the driving amount of the stage 3210 by the stage driving device 3260 is constantly monitored by the position detection device 3280.

  Hereinafter, the operation of the apparatus shown in FIG. 45 will be described. First, the workpiece W is transported and placed on the stage 3210 of the laser annealing apparatus. Next, the workpiece W on the stage 3210 is aligned with the irradiation optical system 3240. Next, while moving the mask 3242 of the irradiation optical system 3240, the combined light CL obtained from the pair of laser light sources 3221 and 3222 is incident on a predetermined region on the workpiece W as a linear beam AB. A thin film of amorphous semiconductor such as amorphous Si is formed on the work W, and a predetermined region of the semiconductor is annealed and recrystallized by irradiation and scanning of the linear beam AB, and a semiconductor having excellent electrical characteristics. A thin film can be provided. The laser annealing as described above is repeated in a plurality of predetermined regions provided in the workpiece W, and the semiconductor thin film is annealed in the plurality of predetermined regions provided in the workpiece W.

  At this time, in the above apparatus, since the combining optical system 3230 spatially joins the pair of laser beams LB1 and LB2 from the pair of laser light sources 3221 and 3222 to form the combined light CL, the pair of laser beams LB1 and LB2 is formed. Can be synthesized with a minimum loss, and after the synthesis, a uniform rectangular beam can be formed on the mask 3242 which is a predetermined surface with respect to the pair of laser beams LB 1 and LB 2 by the homogenizer 3241. Further, the linear beam AB incident on the workpiece W is an efficient combination of the laser beams LB1 and LB2, and various laser annealing is possible.

  FIG. 46 is a view for explaining the synthesis optical system 3230 and the surrounding structure. As described above, the combining optical system 3230 includes the pair of knife edge mirrors 3231 and 3232, and allows the first beam LB1 to pass between the pair of knife edges 3231a and 3232a, and the second beam LB2 to pass the pair of knife edges 3231a. , 3232a. The divergence optical system 3271 for finely adjusting the image forming position of the first beam LB1 by the homogenizer 3241 is an afocal system in which a convex lens 3271a and a concave lens 3271b are combined. The telescope optical system 3272 that matches the beam size of the second beam LB2 with the beam size of the first beam LB1 is also an afocal system in which a concave lens 3272a and a convex lens 3272b are combined. A turn mirror 3233 is provided between the telescope optical system 3272 and the combining optical system 3230 to guide the second beam LB2. On the other hand, the homogenizer 3241 to which the combined light CL obtained by combining both laser beams LB1 and LB2 is made up of first to fourth cylindrical lens arrays CA1 to CA4 and a convex condenser lens 3241a. Here, the first and third cylindrical lens arrays CA1, CA3 have a curvature in a cross section parallel to the paper surface, and the second and fourth cylindrical lens arrays CA2, CA4 are in a cross section perpendicular to the paper surface and including the optical axis. Has curvature.

  The outline of the operation will be described below. The first beam LB1 passes between the knife edges 3231a and 3232a, that is, through the central pupil region including the optical axis OA of the homogenizer 3241, and the second beam LB2 is divided into two by the knife edge mirrors 3231 and 3232. The light beams enter the homogenizer 3241 through both ends of the beam LB 1, that is, through a pair of outer pupil regions of the homogenizer 3241. The homogenizer 3241 has a size of an entrance pupil for two beams so that the combined light CL can enter, and the lens system such as the condenser lens 3241a is corrected for aberration in accordance with the entrance pupil.

  The synthesized light CL incident on the homogenizer 3241 forms a secondary light source divided into the number of segments constituting the cylindrical lens by the first to fourth cylindrical lens arrays CA1 to CA4. The split light beam from the secondary light source enters the condenser lens 3241a and is superimposed on the irradiated surface IS arranged at the back focus position of the condenser lens 3241a to form a uniform rectangular beam.

  Here, the divergence optical system 3271 and the telescope optical system 3272 are different from each other in the focus position of the rectangular beam formed by the homogenizer 3241 due to the beam characteristics of the first beam LB1 and the second beam LB2 and the difference therebetween. This prevents differences in beam size and uniformity.

  The former divergence optical system 3271 adjusts the best focus position and beam size by the homogenizer 3241 by slightly changing the NA of the first beam LB1 incident on the homogenizer 3241. The latter telescope optical system 3272 matches the beam size of the second beam LB2 with the beam size of the first beam LB1 incident on the homogenizer 3241. Thus, the same uniformity can be obtained by making the numbers of divisions of the cylindrical lens arrays CA1 to CA4 coincide for both laser beams LB1 and LB2.

  Details of the operation will be described below. The first beam LB1 enters a divergence optical system 3271 for the first beam via a beam delivery (turn mirror or the like) not shown. The divergence optical system 3271 is an approximately equal afocal system, and the beam size of the first beam LB1 emitted from the divergence optical system 3271 is almost changed by changing the distance between the two lenses 3271a and 3271b. Without any change, the NA of the first beam LB1 can be slightly changed. In a specific embodiment, the variable adjustment range of the output NA (the spread angle of the first beam LB1) by the divergence optical system 3271 is about several mrad. Note that the two lenses 3271a and 3271b are a convex and concave two-group system, and their respective powers are small, so that even if the distance between the two lenses 3271a and 3271b is changed, almost no change in aberration occurs.

  The first beam LB1 emitted from the divergence optical system 3271 only passes between the two knife edge mirrors 3231 and 3232, that is, the optical axis center side of the homogenizer 3241. The first beam LB1 that has passed between the knife edge mirrors 3231 and 3232 is then incident on the center of the cylindrical lens array CA1 of the homogenizer 3241 (the cylindrical lens assigned to the first beam LB1), and the number of cylindrical lenses (FIG. 46). Is divided into 6). The divided beams are superimposed by a condenser lens 3241a to form a uniform beam on the irradiated surface IS.

  On the other hand, the second beam LB2 enters the telescope optical system 3272 for the second beam through beam delivery (not shown). The second beam LB2 incident on the telescope optical system 3272 is enlarged or reduced by this optical system to have the same beam size as that of the first beam LB1, and is emitted therefrom to go to the combining optical system 3230. In the combining optical system 3230, the second beam LB2 is divided into two beam portions LB2a and LB2b by the knife edge mirrors 3231 and 3232, and respectively passes through both ends of the first beam LB1 toward the homogenizer 3241. Both beam portions LB2a and LB2b are incident on the outside of the optical axis center of the homogenizer 3241, that is, on both ends of the cylindrical lens array CA1 of the homogenizer 3241 (the cylindrical lenses assigned to the second beam LB2), and the number of cylindrical lenses (FIG. In 46, it is divided into a total of 6 pieces each of 3 pieces on the top and bottom. The divided beams are superimposed by a condenser lens 3241a to form a uniform beam on the irradiated surface IS.

  In the above description, it is described that both the first beam LB1 and the second beam LB2 “form a uniform beam on the irradiated surface IS”, but in fact, the best focus position of both is the divergence angle of the beam mainly emitted from the light source. May differ due to differences in characteristics such as In addition, when the best focus is different, the beam size is often different. Therefore, it is necessary to compensate for the difference in characteristics between the first beam LB1 and the second beam LB2. For this reason, the best focus position of the second beam LB2 is set as the true irradiated surface IS (reference surface), and the best focus position of the first beam LB1 is made to coincide with this reference surface. Specifically, the exit NA of the first beam LB 1, that is, the incident NA when viewed from the homogenizer 3241 is changed by the divergence optical system 3271. When the incident NA viewed from the homogenizer 3241 is changed, the best focus position after passing through the homogenizer 3241 changes accordingly. As a result, the best focus position of the first beam LB1 can be finely adjusted to match that of the second beam LB2. Note that the correspondence between the output NA and the shift of the best focus position differs depending on the lens configuration of the homogenizer 3241, and thus detailed description of such adjustment is omitted.

  FIG. 47 is a diagram for conceptually explaining the structure of a laser annealing apparatus which is an embodiment of the laser processing apparatus according to the present invention.

  This laser annealing apparatus is for heat-treating a workpiece W in which a semiconductor thin film such as amorphous Si is formed on a glass substrate, and an excimer laser for heating the semiconductor thin film and other laser light sources for generating laser light AL. 3310, an irradiation optical system 3320 that makes this laser beam AL linear (fine rectangle) and enters the workpiece W with a predetermined illuminance, and the workpiece W is placed and the workpiece W is smoothed in the XY plane. And a process stage device 3330 that can be rotated around the Z axis.

  The irradiation optical system 3320 includes a homogenizer 3321 having a uniform distribution of incident laser light AL, a mask assembly 3322 having a mask formed with a slit for narrowing the laser light AL that has passed through the homogenizer 3321 into a thin rectangular beam, and a slit of the mask. And a projection lens 3323 for reducing and projecting an image on the workpiece W. Among these, the mask assembly 3322 is supported by the mask stage device 3340 so as to be exchangeable, and is driven by the mask stage device 3340 so that it can be smoothly translated in the XY plane and rotated around the Z axis. It is movable.

  The process stage device 3330 is accommodated in the process chamber 3350, and can support the workpiece W in the process chamber 3350 and can be appropriately moved with respect to the irradiation optical system 3320. The laser beam AL from the irradiation optical system 3320 is irradiated onto the workpiece W supported at a proper position in the process chamber 3350 through the window 3350a.

  Note that, on both sides of the projection lens 3323, a position detection device or the like including a light projecting device 3361 that makes the inspection light incident on the surface of the workpiece W through the window 3350a and a light receiving device 3362 that detects the reflected light from the surface of the workpiece W Is installed so that the workpiece W on the process stage device 3330 can be precisely aligned with the irradiation optical system 3320.

  Here, the mask stage device 3340 and the projection lens 3323 are suspended and fixed to a gantry 3365 extending from the process chamber 3350. Although not shown, the homogenizer 3321 is indirectly fixed to the gantry 3365.

  The mask assembly 3322 supported by the mask stage device 3340 is suspended from the lower end of the columnar mounting jig 3370 and inserted into the bottom of the insertion port 3340a provided in the mask stage device 3340, and is fixed thereto. The mask assembly 3322 is arranged to be inclined with respect to the mask 3322a above the mask 3322a with the mask 3322a formed with a slit, and damage to other optical elements is caused by the return light from the mask 3322a. A reflection member 3322b to be prevented and a field lens 3322c for adjusting the spread angle of the laser light AL incident on the mask 3322a are provided, and the mask 3322a, the reflection member 3322b, and the field lens 3322c are integrally held.

  FIG. 48 is a view for explaining the structure of the mask stage device 3340 and the support of the mask assembly 3322. FIG. 48 (a) is a side sectional view of the mask stage device 3340 and the like, and FIG. These are top views of the attachment jig 3370.

  The mask stage apparatus 3340 includes an X-axis stage unit 3441 that translates the mask assembly 3322 in the X-axis direction, a Y-axis stage unit 3442 that translates the mask assembly 3322 in the Y-axis direction together with the X-axis stage 3441, and X The shaft stage 3441 and the Y-axis stage unit 3442 include a θ-axis stage 3443 that rotates and moves around the Z-axis. The X-axis stage 3441 and the Y-axis stage unit 3442 are slidably connected via a slide guide 3445. On the other hand, the Y-axis stage unit 3442 and the θ-axis stage 3443 are rotatably connected via a bearing 3446.

  The mask assembly 3322 has a tapered outer surface TP1 that narrows downward on the outer periphery of a cylindrical mask holder body 3422d that holds the mask 3322a, the reflecting member 3322b, and the field lens 3322c. On the other hand, the X-axis stage 3441 also has a tapered inner surface TP2 fitted to the tapered outer surface TP1 in a circular opening provided in the bottom portion 3441a. As a result, only by inserting the mask assembly 3322 into the circular opening provided in the bottom portion 3441a of the X-axis stage 3441, the taper outer surface TP1 and the taper inner surface TP2 are fitted, and the mask assembly with respect to the X-axis stage 3441. 3322 can be precisely aligned. Further, the mask assembly 3322 is urged downward with a constant force by an annular fixing nut 3425 screwed into the bottom 3441 a of the X-axis stage 3441.

  The mask assembly 3322 and the fixing nut 3425 are attached to the bottom portion 3441a of the X-axis stage 3441 using an attachment jig 3370. The mask assembly 3322 has a recess 3422g that engages with a hook-shaped hooking member 3471 provided on the lower surface of the attachment jig 3370, and moves up and down as the attachment jig 3370 is operated. Thereby, the mask assembly 3322 can be easily and reliably inserted into the circular opening provided in the bottom 3441a of the X-axis stage 3441. The fixing nut 3425 also has a recess 3425g that engages with the hooking member 3471 of the attachment jig 3370, and moves up and down as the attachment jig 3370 is operated. As a result, the mask assembly 3322 can be simply and reliably fixed by screwing the fixing nut 3425 from above the mask assembly 3322 inserted in the bottom 3441a of the X-axis stage 3441.

  The mounting jig 3370 is a cylindrical main body 3470a, a disk-shaped support member 3470b that is fixed to the lower end of the main body 3470a and supports the hooking member 3471, and the main body 3470a is rotated together with the support member 3470b and moved up and down. Handle 3470c. Note that the handle 3470c includes a handle 3473 extending in three directions as shown in FIG.

  With the mask assembly 3322 attached to the lower part of the attachment jig 3370, the mask assembly 3322 is inserted from the insertion port 3440a of the mask stage device 3340 and the mask assembly 3322 is lowered to the bottom 3441a. When rotated in the direction, the mask assembly 3322 is separated from the mounting jig 3370.

  Next, the fixing nut 3425 is attached to the lower part of the attachment jig 3370 in the same manner as the mask assembly 3322 and is inserted from the insertion port 3440a of the mask stage apparatus 3340. When the lower end is reached, if the fixing nut 3425 is rotated counterclockwise and tightened to a predetermined position, the mask assembly 3322 is pressed against the bottom 3441a with a constant pressure of the disc spring 3425c. At this time, the tapered outer surface TP1 provided on the mask holder main body 3422d and the tapered inner surface TP2 provided on the bottom 3441a are in close contact with each other, so that the mask assembly 3322 can be attached to the mask stage device 3340 with high accuracy. Thereafter, when the attachment jig 3370 is rotated clockwise, the fixing nut 3425 is separated from the attachment jig 3370, and only the attachment jig 3370 can be taken out.

  When the mask assembly 3322 is detached from the mask stage apparatus 3340, the above operation may be followed in the opposite manner. That is, the mounting jig 3370 is inserted into the insertion port 3440a of the mask stage device 3340, the fixing nut 3425 is loosened and removed, and the tip of the same mounting jig 3370 is hooked on the recessed portion 3422g on the mask assembly 3322. Thereafter, when the attachment jig 3370 is slowly pulled up, the mask assembly 3322 is pulled out integrally with the attachment jig 3370. Further, the removal of the mask 3322a and the reflecting member 3322b from the mask assembly 3322 can be easily performed by a procedure opposite to that for attaching them, although the detailed description is omitted.

  The mask 3322a is attached to the mask stage device 3340 with high accuracy by the above operation. However, for more precise positioning, the alignment mark attached to the mask surface is visually observed with a CCD camera (not shown) or the like. While adjusting it.

  Next, a position measuring apparatus and method according to an embodiment of the present invention will be specifically described with reference to the drawings.

  FIG. 49 is a diagram for conceptually explaining the structure of a laser annealing apparatus incorporating the position measurement apparatus of the embodiment. The laser annealing apparatus includes a laser light source 3510 for generating an excimer laser or other laser light AL for heating a semiconductor thin film such as amorphous Si formed on a work W, which is a glass plate, and the laser light AL in a line or An irradiation optical system 3520 that is incident on the workpiece W with a predetermined illuminance in the form of a spot, and a stage 3530 on which the workpiece W is placed and can be moved smoothly in the XY plane and can be rotated about the Z axis. And a stage driving device 3540 which is a driving means for moving the stage 3530 on which the workpiece W is placed with respect to the irradiation optical system 3520 and the like by a necessary amount. Note that the irradiation optical system 3520 includes, for example, a homogenizer 3520a that uniformly distributes the incident laser beam AL, a mask 3520b that has a slit that narrows the laser beam AL that has passed through the homogenizer 3520a into a predetermined beam shape, and a slit image of the mask 3520b. And a projection lens 3520c for reducing and projecting onto the workpiece W.

  In addition to the stage 3530 and the stage driving device 3540, the laser annealing device includes a moving amount measuring device 3550 that detects the moving amount of the stage 3530 as optical information or electrical information, and a workpiece. A coaxial type two-lens two-magnification projection optical system 3560 that forms an alignment mark on W and a first imaging that converts a relatively low-magnification first-magnification image projected by the projection optical system 3560 into an image signal. An image output from the device 3571, a second imaging device 3572 that converts a relatively high-magnification second-magnification image projected by the projection optical system 3560 into an image signal, and first and second imaging devices 3571 and 3572 Illumination light is supplied to an image processing device 3580 that performs appropriate signal processing on the signal and a projection optical system 3560 for illuminating the surface of the workpiece W. And a bright lamp 3565. The main controller 3585 controls not only the position measuring device but also the operation of each part of the laser annealing device.

  The projection optical system 3560 will be described in more detail. The projection optical system 3560 is a coaxial type two-lens two-magnification optical system as described above, and the image of the workpiece W on the stage 3530 is placed on the first imaging device 3571 at a first magnification of a relatively low magnification. The first lens systems 3561a and 3561b to be projected, the second lens systems 3562a and 3562b that project the first lens systems 3561a and 3561b onto the second imaging device 3572 at a second magnification that is relatively high, and the image light IL from the workpiece W are divided. Illumination light from the first lens system 3561a, 3561b and the second lens system 3562a, 3562b, the half mirror 3563, and the illumination lamp 3565 for generating illumination light having a wavelength different from that of the laser light source 3510 are supplied via the cable 3566. And an epi-illumination system 3567 for guiding it onto the optical axis of the two imaging device 3572.

  Here, the first lens systems 3561a and 3561b and the second lens systems 3562a and 3562b are coaxial optical systems that share an optical axis. That is, the image light IL emitted from the workpiece W along the optical axes of the first lens systems 3561a and 3561b is incident on the center of the field of the first imaging device 3571 when reflected by the half mirror 3563, and When the light passes through the half mirror 3563, the light enters the center of the field of view of the second imaging device 3572 along the optical axes of the second lens systems 3562a and 3562b. The epi-illumination system 3567 is also arranged coaxially with the second lens systems 3562a and 3562b, and the area on the work W corresponding to the field of view of the first and second imaging devices 3571 and 3572 is illuminated uniformly. The

  The first imaging device 3571 is composed of a CCD element that is a solid-state imaging element, and constitutes a CCD camera 3573 together with the lens 3561b. The CCD camera 3573 is fixed to one end of a lens barrel 3575 that houses a lens 3561a. On the other hand, the second imaging device 3572 is also composed of a CCD element, and constitutes a CCD camera 3574 together with the lens 3562b. The CCD camera 3574 is fixed to one end of a lens barrel 3576 that houses a lens 3562a. The other ends of both lens barrels 3576 are fixed to a case for housing the half mirror 3563.

  FIG. 50 is a diagram showing an example of the arrangement of alignment marks formed on the surface of the workpiece W placed on the stage 3530 in FIG. The alignment marks M1 and M2 shown in the figure are double patterns obtained by combining magnitudes of bright and dark binary cross patterns.

  The first alignment mark M1 is formed at one of the four corners of the workpiece W, and the second alignment mark M2 is formed at the other four corners of the workpiece W. The reason why the first and second alignment marks M1 and M2 are formed at two positions on the workpiece W is to detect not only the position of the workpiece W but also the rotation of the workpiece W. That is, by measuring the positions of the first and second alignment marks M1 and M2, the coordinates of the two reference points on the workpiece W can be known, and the workpiece W is moved to an appropriate position after correcting the posture of the workpiece W. Alignment is possible.

  Next, the operation of the laser annealing apparatus of FIG. 49 will be described. First, the workpiece W is transported and placed on the stage 3530 of the laser annealing apparatus. Next, the workpiece W on the stage 3530 is aligned with the irradiation optical system 3520 for guiding the laser beam AL for annealing. Next, the laser beam AL from the laser light source 3510 is incident on the workpiece W in a line shape or a spot shape while appropriately moving the stage 3530 with respect to the irradiation optical system 3520. A thin film of an amorphous semiconductor such as amorphous Si is formed on the work W, and the semiconductor is annealed and recrystallized by irradiation with the laser beam AL to provide a semiconductor thin film having excellent electrical characteristics. it can.

  When aligning the workpiece W on the stage 3530 with respect to the irradiation optical system 3520, a position measuring device is used. That is, the stage 3530 is appropriately moved by the stage driving device 3540, and the first alignment mark M1, that is, the global mark M11 and the fine mark M12 are guided into the field of view of the first imaging device 3571 (step S1). Since the position of the workpiece W on the stage 3530 is within a certain conveyance accuracy range (0.5 to 1 mm in the embodiment), the stage 3530 is appropriately moved with respect to the projection optical system 3560, and the first lens is moved. The first alignment mark M1 can be moved in the field of view of the systems 3561a and 3561b, that is, in the field of view of the first imaging device 3571 (in the embodiment, the size is 5 mm). For example, if the position of the first alignment mark M1 on the workpiece W is previously input and stored as data, the stage 3530 is appropriately moved based on the position data of the first alignment mark M1, and the first imaging device 3571 is obtained. It is guaranteed that the first alignment mark M1 is almost surely placed in the image field.

  Next, the position of the global mark M11 among the first alignment marks M1 is measured by performing image signal processing from the first imaging device 3571 with a low magnification in the image processing device 3580 (step S2). Note that there is a precise correspondence between the pixel of the first image pickup device 3571 and the distance on the stage 3530, and the global mark M11 from the center of the first image pickup device 3571, that is, the optical axis of the first lens systems 3561a and 3561b. The XY component of the distance to the center of can be accurately determined.

  Next, while measuring the movement amount with the movement amount measuring device 3550, the stage driving device 3540 is driven to move the stage 3530 in the XY plane, whereby the global mark M11 is placed on the optical axes of the first lens systems 3561a and 3561b. Are matched with each other (step S3). Note that the movement amount measured by the movement amount measuring device 3550 corresponds to the distance obtained in step S2. At this time, the positioning accuracy by the global mark M11 is about 10 μm in the embodiment. By the search alignment as described above, the fine mark M12 arranged at the center of the global mark M11 can be reliably moved into the field of view (0.5 mm size in the embodiment) of the second imaging device 3572 with a high magnification. it can.

  Next, the position of the fine mark M12 is measured by processing the image signal from the second imaging device 3572 in the image processing device 3580 (step S4). Note that there is a precise correspondence between the pixel of the second image pickup device 3572 and the distance on the stage 3530, and the fine mark M12 from the center of the second image pickup device 3572, that is, the optical axis of the second lens systems 3562a and 3562b. The distance to the center of the can be determined accurately. The position measurement accuracy by the fine mark M12 is about 1 μm in the embodiment.

  Here, the projection optical system 3560 that measures the position of the fine mark M12 has a predetermined positional relationship with respect to the irradiation optical system 3520 for laser annealing, and this positional relationship is measured or adjusted in advance. Yes. Therefore, the distance from the optical axes of the second lens systems 3562a and 3562b to the center of the fine mark M12 is converted into the distance from the laser annealing irradiation optical system 3520 to the center of the fine mark M12 based on the positional relationship. (Step S5). As described above, the precise coordinates of the first alignment mark M1 can be determined.

  The above measurement (steps S1 to S5) is performed in the same manner for the second alignment mark M2, and precise coordinates can be determined for the second alignment mark M2 (step S6). In the embodiment, one pixel of the second imaging device 3572 is set to 1 μm, and position detection is performed with an accuracy of about 1 μm.

  Next, based on the precise coordinate measurement results of the first and second alignment marks M1, M2 obtained in steps S5, S6, the work W is aligned with respect to the irradiation optical system 3520 (step S7). Specifically, the position and rotation of the workpiece W are obtained based on the coordinate measurement values of the fine marks of the first and second alignment marks M1 and M2 with the irradiation optical system 3520 as a reference, and laser annealing is performed from the result. The workpiece W is arranged in a necessary rotational posture at a necessary position at the start.

  Next, the amorphous thin film on the workpiece W is scanned while the laser beam AL such as a laser spot or a laser line irradiated from the irradiation optical system 3520 is scanned on the workpiece W using the stage driving device 3540 and the movement amount measuring device 3550. Are recrystallized to sequentially form a polycrystalline thin film on the workpiece W. At this time, the laser beam AL can be scanned by moving the stage 3530 in the X direction or the Y direction by the stage driving device 3540 while observing the movement amount by the movement amount measuring device 3550. Further, by providing the irradiation optical system 3520 with a scanning function, for example, by moving the mask 3520b in the irradiation optical system 3520, the laser light AL can be scanned.

According to the position measurement method of the first embodiment described above, after the work W is transported and placed on the stage 3530, highly accurate position measurement can be performed only by the movement of the work W by search alignment using the global mark M11. This makes it possible to measure the position of the workpiece W quickly. Further, since the outlines of the global mark M11 and the fine mark M12 are similar, the image measurement algorithm for measuring both the marks M11 and M12 can be made almost the same, so that the arithmetic processing and the like can be simplified. .

  FIG. 51 is a perspective view for explaining the arrangement of alignment marks formed on the surface of the workpiece W placed on the stage 3530 (see FIG. 49).

  The first and second global marks M111 and M211 are formed at any one of the four corners of the workpiece W, respectively. Both global marks M111 and M211 have the same coordinates for the workpiece X axis and different coordinates for the workpiece Y axis. On the other hand, the first and second fine marks M112 and M212 are arranged in the vicinity of the processing area PA on the workpiece W, respectively. Both fine marks M112 and M212 have the same coordinates for the workpiece X axis and different coordinates for the workpiece Y axis. The processing area PA is an area where the slit image of the mask 3520b is to be projected by the projection lens 3520c, and is arranged on the work W at an appropriate interval (only two are illustrated in the drawing).

  By measuring the positions of the first and second global marks M111 and M211, the coordinates of the two reference points around the work W can be known, and after correcting the posture of the work W, the first and second fine marks M112, Search alignment (global alignment) is possible in which each of M212 is put into the field of view of the second imaging device 3572 (see FIG. 49) on the high magnification side. On the other hand, since the precise coordinates of the two reference points around the machining area PA corresponding to the first and second fine marks M112 and M212 can be known, the workpiece W is moved as appropriate, and the slit of the mask 3520b. The image can be accurately projected onto the processing area PA.

  FIG. 52 is a diagram for conceptually explaining the structure of a laser annealing apparatus which is an embodiment of the laser processing apparatus according to the present invention.

  This laser annealing apparatus is for heat-treating a workpiece W in which a semiconductor thin film such as amorphous Si is formed on a glass substrate, and an excimer laser for heating the semiconductor thin film and other laser light sources for generating laser light AL. 5310, an irradiation optical system 5320 for making this laser beam AL line-like (precisely a fine rectangle) and making it incident on the workpiece W at a predetermined illuminance, and placing the workpiece W on the XY plane Of the process stage device 5330 that can be smoothly translated and rotated around the Z axis, a stage control device 5340 that controls the operation of the process stage device 5330, and the operation of each part of the laser annealing device And a main control device 53100 that controls the entire system.

  The irradiation optical system 5320 includes a homogenizer 5320a that uniformly distributes the incident laser beam AL, a mask 5320b that has a slit that narrows the laser beam AL that has passed through the homogenizer 5320a into a rectangular beam shape, and a slit image of the mask 5320b. It includes a projection lens 5320c which is a projection optical system that performs reduction projection on the top. Of these, the mask 5320b is exchangeably held by the mask stage device 5350, can be smoothly translated in the XY plane, and can be rotated about the Z axis. The operation of the mask stage device 5350 is controlled by a stage control device 5360 so that the timing and amount of translation and rotation of the mask 5320b can be monitored. The mask stage device 5350 and the stage control device 5360 constitute a mask drive device.

  Process stage apparatus 5330 is housed in process chamber 5370. The laser beam AL from the irradiation optical system 5320 is irradiated onto the workpiece W held by the process stage device 5330 disposed in the process chamber 5370 through the window 5370a. The translational movement amount and rotational movement amount of the process stage device 5330 are monitored by the stage control device 5340.

  A work alignment camera 5380 is fixed immediately above a corner portion of a window 5370a provided on the upper surface of the process chamber 5370. The work alignment camera 5380 is for detecting a positional shift of the work W placed on the process stage device 5330, and includes an imaging optical system and an image sensor such as a CCD. An image signal output from the work alignment camera 5380 is processed by an image processing device 5381. A signal output from the image processing device 5381 is input to the main control device 53100 and is used when the workpiece W is aligned with the projection lens 5320c constituting the irradiation optical system 5320.

  A mask alignment camera 5384, which is an imaging device, is fixed immediately below the corner of the mask 5320b. The mask alignment camera 5384 is for detecting a positional shift of the mask 5320b held by the mask stage device 5350. The image signal output is processed by the image processing device 5385, and the photographed image is a display device. It is displayed on the display 5386 and used when aligning the mask 5320b with the workpiece W.

  Here, the mask stage device 5350 and the projection lens 5320 c are fixed to a gantry 5390 extending from the process chamber 5370. The mask alignment camera 5384 is also fixed to the gantry 5390 via a support member 5391. Although detailed description of the support member 5391 is omitted, the position of the mask alignment camera 5384 with respect to the mask stage device 5350 can be adjusted. That is, the mask alignment camera 5384 translates in the XY plane, rotates around the Z axis, and can be firmly fixed to the gantry 5390 after the necessary adjustment movement is completed. It has become.

  In the above apparatus, the mask 5320b is moved with respect to the projection lens 5320c by the mask stage apparatus 5350 and the image of the mask alignment mark AM is displayed by the display 5386, so that the position of the mask 5320b is visually confirmed in real time. Precise and reliable positioning can be performed.

It is a conceptual diagram of the conventional excimer laser annealing apparatus. It is a timing chart for demonstrating the conventional laser operation method. It is the figure which showed the example of the pulse distribution of a laser pulse intensity | strength. It is the figure which showed the example of a silicon film temperature change. It is the figure which showed an example of the laser pulse waveform. It is the figure which showed the irradiation rate, the cooling rate, and the cooling rate which amorphization produces. It is the figure which showed the example of a calculation result of a silicon thin film temperature change. It is a figure which shows the crystal | crystallization form of the silicon thin film with respect to each irradiation intensity | strength. It is the figure which showed the maximum cooling rate after 2nd pulse injection | throwing-in, and the cooling rate of the freezing point vicinity. It is the figure which showed the process condition dependence of the average crystal grain diameter. It is a figure for demonstrating embodiment (whole) of the exposure apparatus of this invention. It is a figure for demonstrating embodiment (alignment method) of the exposure apparatus of this invention. It is a figure for demonstrating embodiment (mask projection method) of the exposure apparatus of this invention. 5 is a timing chart for explaining an embodiment (control example) of the exposure apparatus of the present invention. It is side surface sectional drawing of the exposure apparatus of this invention, a conveyance chamber, and a plasma CVD chamber. It is a top view of composite apparatuses, such as exposure apparatus of this invention, a transfer chamber, and a plasma CVD chamber. It is side surface sectional drawing of the plasma CVD chamber of this invention. It is sectional drawing for demonstrating the TFT manufacturing process of this invention. It is sectional drawing for demonstrating the TFT manufacturing process using the alignment mark of this invention. It is sectional drawing for demonstrating the TFT manufacturing process including the alignment mark formation of this invention. It is a figure used in order to demonstrate the Example of the pulse oscillation delay control of the several light source by this invention. It is a figure used in order to explain an example of pulse oscillation delay of a plurality of light sources by the present invention. It is the figure which showed the laser annealing apparatus incorporating the focus adjustment apparatus by this invention. 1 is a diagram illustrating a schematic configuration of a multifunction machine according to the present invention. It is the figure which expanded and showed the bellows in FIG. It is the figure which showed the relationship between the process chamber and vibration isolator in FIG. It is the figure which expanded and showed the structure of the vibration isolator in FIG. It is a longitudinal cross-sectional view of the in-vacuum linear actuator drive mechanism by this invention. It is a longitudinal cross-sectional view by line CC in FIG. It is a figure for demonstrating schematic structure of the drive mechanism of FIG. It is a top view of the mask stage drive mechanism by this invention. FIG. 32 is a longitudinal sectional view taken along line BB in FIG. 31. It is a top view which shows the stage apparatus provided with the pneumatic tilt mechanism by this invention in the state which removed the stage. It is a side view of the pneumatic tilt mechanism by this invention. It is a figure for demonstrating the return light removal method and apparatus by this invention. It is a longitudinal cross-sectional view which shows the structure of embodiment of this invention. It is an expanded sectional view of various holes formed in a partition part. It is a longitudinal cross-sectional view which shows the structure of embodiment of this invention. It is a longitudinal cross-sectional view which shows the structure of embodiment of this invention. It is a block diagram which shows the structure of the film-forming apparatus of the participating silicon thin film by the DPR type | formula based on this invention. It is a graph which shows an example of the change state of the supply amount of material gas. It is a graph which shows the other example of the change state of the supply amount of material gas. 1 is a schematic side sectional view of a thin film forming apparatus according to an embodiment of the present invention. FIG. 44 is a schematic side sectional view showing the configuration of a modified species supply unit 8133 provided in the transfer chamber of the apparatus shown in FIG. 43. It is a figure used in order to demonstrate the Example of the synthetic | combination optical system of multiple beams by this invention. It is a figure used in order to demonstrate the Example of the synthetic | combination optical system of multiple beams by this invention. It is a figure used in order to demonstrate the Example of the mask stage mechanism by this invention. It is a figure used in order to demonstrate the Example of the mask stage mechanism by this invention. FIG. 3 is a diagram used for explaining a rectangular beam precision alignment apparatus and method according to the present invention. It is the figure which showed the example of alignment mark arrangement | positioning used in order to demonstrate this invention. It is a perspective view explaining arrangement | positioning of an alignment mark. It is a figure which shows the structure of the laser annealing apparatus which is embodiment of this invention.

Explanation of symbols

5410 Laser light source 5420 Irradiation optical system 5421 Homogenizer 5422 Mask assembly 5522a Mask 5522b Reflective member 5522c Field lens 5423 Projection lens 5525 Reflection mirror 5526 Beam damper 5430 Process stage device 5440 Mask stage device 5450a Process chamber 5450a Window S slit A SS rectangular slit W work 5310 laser light source 5320 irradiation optical system 5320a homogenizer 5320b mask 5320c projection lens 5330 process stage device 5340 stage control device 5350 mask stage device 5360 stage control device 5370 process chamber 5380 work alignment camera 5384 mask alignment Camera 5386 Display 53100 Main controller AL Laser beam AM Mask alignment mark W Work 5201 Stage 5102 Base 5202-1 Support base 5103 Leaf spring 5104-1 to 5104-3 Bellows cylinder 5105-1 to 5105-3 Displacement sensor 4601 Base plate 1
4702 Rotary encoder 4703 Cross roller bearing 4704-1 Rotating shaft 4604 θ-axis movable part 4605 θ-axis drive motor 4706 Y-axis linear bearing 4707 Y-axis movable part 4608 Y-axis linear motor 4709 Y-axis linear encoder 4610 X-axis movable part 4710-1 Boss 4611 Lift air bearing 4612 X axis linear encoder 4713 X axis linear motor 4714 Mask 4615, 4616 Yaw guide air bearing 4617 Pull spring 4718 Magnet 4620 Preload piston 4301 Work 4302 Stage 4403 Trolley 4304 Water cooling plate 4306 X axis base 4307 X Axis linear bearing 4408 X axis linear motor 4309 Stage base 4410 X axis linear encoder 4314 Y-axis base 4315, 4320 Y-axis linear bearings 4318, 4323 Y-axis linear motor 4316, 4321 Y-axis linear encoder 43100 Vacuum chamber 3901 Glass substrate 3910 CVD device 3920 Laser annealing device 3921 Process chamber 3922 Process stage 3923 Transmission window 3924 Mounting platform 3925 Laser irradiation system 3926 Laser oscillator 3927 Reflection mirror 3928 Mask stage 3929 Lens optical system 3940 Vibration isolator 4242 Air damper 4244 Compressor 4246 Piston part 4247 First stopper member 4148 Second stopper member 4149 Position detector 3950 Floor 3960 Substrate conveyance Robot 3970 Transfer chamber 3971 Bellows 42100 Control equipment 3710 Laser light source 3720 Irradiation optical system 3730 Stage 3740 Stage driving device 3742 Tilt device 3744 Translation device 3750 Movement measuring device 3760 Tilt measuring device 3770 Non-contact displacement meter 3771 Light projecting unit 3772 Light receiving unit 3780 Main controller 3790 Chamber DL Inspection light RL Reflected light T Measurement target W Work θX, θY Tilt angle 3510 Laser light source 3520 Irradiation optical system 3530 Stage 3540 Stage driving device 3550 Movement amount measurement device 3560 Projection optical system 3561a, 3561b First lens system 3562a, 3562b Second lens system 3565 Illumination Lamps 3571, 3572 First and second imaging devices 3573, 3574 Camera 3580 Image processing device 3585 Main controller IL Image light M1, M2 First and second apertures Ment mark 3310 laser light source 3320 irradiation optical system 3321 homogenizer 3322 mask assembly 3322a mask 3322b reflecting member 3322c field lens 3422d mask holder body 3422g recessed portion 3323 projection lens 3425 fixing nut 3425g recessed portion 3330 process stage device 3340a mask stage device 3340 3350 Process chamber 3350a Window 3365 Base 3370 Jig 3470a Main body 3470b Support member 3470c Handle 3471 Hooking member AL Laser light TP1 Tapered outer surface TP2 Tapered inner surface W Work 3110 Laser generator 3111 First laser oscillation device 3112 Second laser oscillation device 3113 Apparatus 3120 Laser irradiation processing unit 312 Projection optical system 3122 Stage 3123 Stage drive system 3130 Main controller 3151 Reference pulse generation circuit 3152 Delay time setting circuit 3153 Arithmetic circuit 3154 Trigger pulse generation circuit 3155 Delay time detection circuit 3161, 3162 Photo sensor 3163, 3164 Amplifier 3170 Photosynthesis system W substrate 3210 Stage 3221, 3222 Laser light source 3230 Synthetic optical system 3231, 3232 Knife edge mirror 3240 Irradiation optical system 3241 Homogenizer 3242 Mask 3243 Projection lens 3250 Mask drive device 3260 Stage drive device 3271 Divergence optical system 3272 Telescope optical system 3280 Position detection device 3280 Main controller AB Line beam CL Composite light LB1 1st beam LB2 2nd beam W Work 7111 Glass substrate 7112 Vacuum container 7114 Bulkhead portion 7115 Plasma generation space 7116 Deposition processing space 7117 Substrate holding mechanism 7120 Electrode 7123 Introducing pipe 7124 Internal space 7125 Through hole 7126 Diffusion hole 7127 Uniform plate 7128 Introducing pipe 7333 Plate-like insulation Member 7423 Second introduction pipe 7512 Film material gas supply device 7513 Mass flow controller (MFC)
7514 Host controller

Claims (23)

  In a semiconductor thin film forming device that modifies a predetermined area of a semiconductor thin film by projecting and exposing an exposure pattern formed on the optical mask onto a semiconductor thin film on the substrate held on the substrate stage, the optical mask or the substrate stage is individually A semiconductor thin film forming apparatus having a mechanism that sequentially scans an exposure pattern by being driven to a constant angle.   2. The semiconductor thin film forming apparatus according to claim 1, further comprising a focusing mechanism for performing focusing of the exposure pattern on the predetermined region of the semiconductor thin film when the exposure pattern is projected onto the semiconductor thin film. Semiconductor thin film forming equipment.   2. The semiconductor thin film forming apparatus according to claim 1, further comprising an inclination correction mechanism for correcting an inclination of the exposure beam with respect to the semiconductor thin film.   2. The semiconductor thin film forming apparatus according to claim 1, further comprising an alignment function for aligning an exposure beam with respect to a mark formed on the substrate on which the semiconductor thin film is deposited.   2. The semiconductor thin film forming apparatus according to claim 1, wherein the semiconductor thin film forming apparatus has a function of holding a substrate on which a semiconductor thin film is deposited on a stage.   A semiconductor thin film forming apparatus that projects a pattern formed on an optical mask onto a semiconductor thin film with an exposure beam and modifies a predetermined region of the semiconductor thin film, and has a combining mechanism that combines a plurality of laser beams as the exposure beam. A semiconductor thin film forming apparatus.   7. The semiconductor thin film forming apparatus according to claim 6, wherein the plurality of laser beams are first and second laser beams, and the synthesizing mechanism is configured such that the second laser beam is delayed with respect to the first laser beam. A semiconductor thin film forming apparatus, wherein the first and second laser beams are combined as the exposure beam so as to irradiate the semiconductor thin film.   In a semiconductor thin film forming apparatus having a processing chamber for projecting and exposing a pattern formed on an optical mask onto a semiconductor thin film on a substrate and modifying a predetermined region of the semiconductor thin film, the processing chamber is a separate processing chamber. And a semiconductor thin film forming apparatus characterized by being connected by a bellows without being exposed to the atmosphere.   In a semiconductor thin film forming apparatus having a processing chamber for projecting and exposing a pattern formed on an optical mask onto a semiconductor thin film on a substrate and modifying a predetermined region of the semiconductor thin film, the processing chamber is a separate processing chamber. A semiconductor thin film forming apparatus, wherein the processing chamber has a vibration isolator and is connected without being exposed to the atmosphere.   Projection exposure of a pattern formed on an optical mask onto a semiconductor thin film on a substrate, and a semiconductor thin film forming apparatus having a processing chamber for modifying a predetermined region of the semiconductor thin film without performing exposure to the atmosphere. An apparatus for forming a semiconductor thin film, comprising: a mechanism for transporting a substrate to a chamber; and the processing chamber includes a vibration isolation device.   11. The semiconductor thin film forming apparatus according to claim 8, wherein the another processing chamber is an insulating film forming chamber for forming an insulating film on a substrate.   11. The semiconductor thin film forming apparatus according to claim 8, wherein the another processing chamber is a semiconductor film forming chamber for forming a semiconductor film on a substrate.   11. The semiconductor thin film forming apparatus according to claim 8, wherein the another processing chamber is a heat treatment chamber for performing heat treatment on the substrate.   11. The semiconductor thin film forming apparatus according to claim 8, wherein the another processing chamber is a plasma processing chamber for performing plasma processing on a substrate.   11. The semiconductor thin film forming apparatus according to claim 8, wherein the processing chamber projects and exposes a pattern formed on the optical mask onto the semiconductor thin film on the substrate with a laser beam. An apparatus for forming a semiconductor thin film, which is a laser processing chamber for modifying a predetermined region, and the other processing chamber is another laser processing chamber.   11. The semiconductor thin film forming apparatus according to claim 8, wherein the another processing chamber has a plasma generation source for generating plasma in a predetermined region in the other processing chamber. A semiconductor thin film forming apparatus, wherein a substrate is disposed in a region outside the predetermined region in a processing chamber.   15. The semiconductor thin film forming apparatus according to claim 14, wherein the another processing chamber has a plasma generation source for generating plasma in a predetermined region in the other processing chamber, and the another processing chamber includes the plasma processing source. The substrate is subjected to the plasma treatment by reacting a gas excited by the plasma in a predetermined region with another gas introduced into the other processing chamber without passing through the predetermined region. There is provided a semiconductor thin film forming apparatus.   11. The semiconductor thin film forming apparatus according to claim 10, wherein a gas is introduced into the other processing chamber (8103 in FIG. 43) and is lower than the pressure of the processing chamber (8101) connected to the other processing chamber. A semiconductor thin film forming apparatus characterized in that the pressure in the other processing chamber is maintained at a pressure.   19. The semiconductor thin film forming apparatus according to claim 18, wherein the gas is a gas that does not adversely affect film formation in the processing chamber.   20. The semiconductor thin film forming apparatus according to claim 19, wherein the gas that does not adversely affect the film formation is hydrogen.   11. The semiconductor thin film forming apparatus according to claim 10, wherein a chemical species having an action of modifying a predetermined region of the semiconductor thin film is supplied as a modified species into the another processing chamber (8103 in FIG. 43). A semiconductor thin film forming apparatus characterized in that a species supply section is provided. 23. The semiconductor thin film forming apparatus according to claim 21, wherein the modified species supply unit has a mutual gas diffusion coefficient as D, a length of a minimum diameter portion of the through hole as L, and a gas flow rate in the through hole as u. , UL / D> 1 (u is m / sec, L is m, D is m ² / sec), and the processing chamber and the other processing chamber are connected only by a plurality of through holes. A semiconductor thin film forming apparatus characterized by the above. 24. The semiconductor thin film forming apparatus according to claim 21, wherein the chemical species is a hydrogen active species.

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