JP2009182147A - Method of manufacturing semiconductor film and optical annealing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a semiconductor film that evaluates optical annealing and a film quality obtained by optical annealing while suppressing the device cost and simplifying the constitution, and to provide an optical annealing device used for the method. <P>SOLUTION: The method of manufacturing a semiconductor film includes the steps of: dividing the light emitted from a light source 2 into at least two beams L1 and L2; improving the crystallinity of the semiconductor film by irradiating a semiconductor film formed on a substrate with at least one of the more than two beams as a film improver light L1; and evaluating the quality improvement of the semiconductor film by irradiating the semiconductor film with at least one beam as an inspection light L2 among at least two beams other than the film improver light and inspecting the content of response of the inspection light L2 obtained from the semiconductor film. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for producing a crystalline semiconductor thin film formed on a substrate and a light annealing apparatus.

  The Si material formed on the glass substrate has to be grown as an amorphous silicon film with low film quality due to process restrictions and the mobility is low, so that it is sufficient for making an element such as a TFT. Unable to get characteristics. Therefore, conventionally, a semiconductor thin film formed on a substrate is modified into a crystal such as polycrystalline silicon by laser annealing, lamp annealing, or the like. And the crystallinity of the modified semiconductor thin film is also inspected.

  Patent Document 1 describes that the crystallized state is confirmed by irradiating the crystallized film with inspection light while crystallizing amorphous silicon by laser annealing, and measuring the glossiness of the film after laser annealing. Has been. FIG. 3 shows the configuration of the crystallization apparatus (annealing apparatus) described in Patent Document 1.

  The crystallization apparatus includes a laser beam irradiation means A including a laser device 1, a reflection mirror 2, an attenuator 3, and a homogenizer 4. The laser light L emitted from the laser device 1 made of an excimer laser is reflected by the reflection mirror 2, passes through the attenuator 3 and the homogenizer 4 in this order, and enters the substrate 5 substantially perpendicularly. The substrate 5 has a configuration in which an undercoat and an amorphous silicon film are laminated on glass. The substrate 5 is mounted on the stage 8, and the stage 8 can be moved in the XY directions by the driving device 9. The driving device 9 is controlled by the control device 11.

  Further, this crystallization apparatus is provided with a measuring means 25 for measuring the glossiness of the thin film as the crystallization state confirmation means B. In addition, the control unit 11 includes a determination unit 26 as a determination unit that confirms the crystallization state based on the measured glossiness. A gloss meter is used as the measuring means 25, and includes a light emitter 27 that irradiates the surface of the substrate 5 with the inspection light L3, and a detector 28 that detects the inspection light L3 that is reflected. When the crystallized crystal grain size is large and granules are not generated, the electron mobility tends to increase, and the gloss level of the excimer laser annealed thin film surface tends to decrease. It has been found by experiments. Utilizing the fact that the state where the glossiness is the lowest has the highest electron mobility, the crystallization state is confirmed. In this way, by measuring the glossiness, the actual crystallization state is confirmed, and when the desired crystallization state is confirmed, the irradiation region of the laser beam L is relatively moved.

  Patent Document 2 discloses that crystallization of an amorphous semiconductor film and inspection of the crystallized semiconductor film are performed on one apparatus. As inspection methods, electron beam diffraction, X-ray diffraction, and Raman scattering have been proposed.

  Patent Document 3 discloses whether a predetermined crystallization state is obtained by irradiating inspection light while crystallizing a semiconductor film using pulsed laser light and detecting the intensity of reflected light of the inspection light. It has been proposed to confirm.

Patent Document 4 discloses that film quality is evaluated by irradiating an inspection light with a predetermined time after forming a lateral crystal by irradiating laser to amorphous silicon or polycrystalline silicon.
JP 2000-133614 A (published on May 12, 2000) JP 2000-174286 A (published June 23, 2000) JP 2002-305146 A (published on October 18, 2002) Japanese Patent Laying-Open No. 2005-277062 (released on October 6, 2005)

  However, in the conventional apparatus and method for performing laser annealing while evaluating film quality, a light source for crystallizing a semiconductor film, such as the laser apparatus 1 and the light emitter 27 in FIG. A light source for evaluating the crystallinity of the semiconductor film is provided separately. Therefore, there arises a problem that the cost of the apparatus increases and the configuration becomes complicated.

  The present invention has been made in view of the above-described conventional problems, and its object is to perform optical annealing and evaluation of film quality obtained by the optical annealing, and to reduce the cost of the apparatus and simplify the configuration. A semiconductor film manufacturing method and an optical annealing apparatus are realized.

  In order to solve the above problems, a method of manufacturing a semiconductor film according to the present invention includes a step of dividing light emitted from a light source into two or more beams, and at least one of the two or more beams is a film. Irradiating a semiconductor film formed on the substrate as modified light to modify the crystallinity of the semiconductor film, and at least one of the two or more beams other than the film modified light. Irradiating the semiconductor film with a beam as inspection light, and detecting a response content of irradiation of the inspection light obtained from the semiconductor film, thereby evaluating a modified state of the semiconductor film. Yes.

  According to the above invention, the light emitted from the light source is divided into two or more beams, and at least one of the beams is irradiated to the semiconductor film formed on the substrate as film-modifying light to obtain crystallinity. On the other hand, the modified state of the semiconductor film is evaluated by detecting the response content by irradiating the semiconductor film with at least one beam other than the film modifying light as the inspection light.

  Therefore, since the film modification light and the inspection light are generated by the same light source, it is not necessary to separately provide the light source for the film modification light and the inspection light as in the conventional case.

  As described above, there is an effect that it is possible to realize a method of manufacturing a semiconductor film that can perform light annealing and evaluation of film quality obtained by the light annealing, and can reduce the cost of the apparatus and simplify the configuration.

  In order to solve the above problems, the semiconductor film manufacturing method of the present invention is characterized in that the semiconductor film is a non-single crystal semiconductor film.

  According to the above invention, when the crystallinity of the non-single-crystal semiconductor film is modified by light annealing, the cost of the apparatus can be reduced and the configuration can be simplified.

  In order to solve the above problems, the method for producing a semiconductor film of the present invention is characterized in that the non-single-crystal semiconductor film comprises amorphous silicon, polycrystalline silicon, amorphous germanium, polycrystalline germanium, amorphous silicon / germanium. It is characterized by being polycrystalline silicon germanium, amorphous silicon carbide, or polycrystalline silicon carbide.

  According to the above invention, there is an effect that the cost of the apparatus can be reduced and the configuration can be simplified with respect to a non-single crystal semiconductor film that is generally used as a target for crystallinity modification by optical annealing.

  In order to solve the above problems, the method for producing a semiconductor film of the present invention is characterized in that the light source is a laser light source.

  According to the above-described invention, the semiconductor film whose crystallinity is modified by laser annealing has the effects that the cost of the apparatus can be reduced and the configuration can be simplified. Further, since the light source light is laser light, there is an effect that it is easily split into two or more beams including film modification light and inspection light.

  In order to solve the above-described problems, the semiconductor film manufacturing method of the present invention is characterized in that the intensity of the film-modified light is made larger than the intensity of the inspection light.

  According to the above invention, since the intensity of the film modification light is larger than the intensity of the inspection light, it is possible to obtain film modification light suitable for crystallinity modification that requires a large intensity. . In addition, the semiconductor film can be prevented from being modified by the inspection light.

  In order to solve the above problems, the method for manufacturing a semiconductor film of the present invention is characterized in that the response content is at least one of scattered light, reflected light, diffracted light, and transmitted light of the inspection light with respect to the semiconductor film. It is characterized by a single intensity or intensity distribution.

  According to the above invention, the response content obtained from the semiconductor film when the semiconductor film is irradiated with the inspection light is at least one of the scattered light, reflected light, diffracted light, and transmitted light of the inspection light with respect to the semiconductor film. Since any one of the intensities or the intensity distributions is obtained, there is an effect that inspection light obtained from a light source common to the film reforming light can be used for a general evaluation item of the modified state of the semiconductor film.

  In order to solve the above problems, a light annealing apparatus of the present invention includes a light source, a splitting optical system that is an optical system that splits light emitted from the light source into two or more beams, and the two or more beams. A modified optical system that is an optical system that modifies the film by irradiating a film formed on the substrate with at least one of them as film-modified light, and the two or more beams Including an inspection optical system that is an optical system for irradiating the film with at least one beam other than the film modification light as the inspection light, and a component that detects the response content of the inspection light irradiation obtained from the film. It is a feature.

  According to the above invention, the light emitted from the light source is divided into two or more beams by using a light annealing device, and at least one of the beams is used as a film modifying light on the film formed on the substrate. Irradiation modifies the film, while at least one beam other than the film modification light is irradiated onto the film as inspection light, and the response content can be detected. If the detection result of the response content is used, the modified state of the film can be evaluated.

  Thus, since the film modification light and the inspection light are generated by the same light source, it is not necessary to separately provide the light source for the film modification light and the inspection light as in the conventional case.

  As described above, there is an effect that it is possible to realize an optical annealing apparatus that is used for optical annealing and evaluation of film quality obtained by the optical annealing, and that can reduce the cost of the apparatus and simplify the configuration.

  In order to solve the above-described problems, the light annealing apparatus of the present invention is characterized in that the light source is a laser light source.

  According to said invention, there exists an effect that the cost reduction of an apparatus and the simplification of a structure can be aimed at with respect to the film | membrane modified | reformed by laser annealing. Further, since the light source light is laser light, there is an effect that it is easily split into two or more beams including film modification light and inspection light.

  In order to solve the above problems, the optical annealing apparatus of the present invention is characterized in that the laser light source is a continuous-wave or pulse-oscillation solid-state laser, semiconductor laser, or gas laser.

Examples of the solid-state laser include continuous wave or pulse oscillation, YAG laser, YVO ₄ laser, YLF laser, YAlO ₃ laser, glass laser, ruby laser, alexandrite laser, titanium sapphire laser, and the gas laser. And continuous wave or pulsed excimer laser, Ar laser, Kr laser, and the like. Further, as the active species having a laser action, for example, trivalent ions (Cr ³⁺ , Nd ³⁺ , Yb ³⁺ , Tm ³⁺ , Ho ³⁺ , Er ³⁺ , Ti ³⁺ ) can be used. In addition, a semiconductor laser, a disk laser, or a fiber laser can be used. In the above configuration, it is preferable that the laser light is converted into a harmonic by a nonlinear optical element. For example, a YAG laser is known to emit laser light having a wavelength of 1064 nm as a fundamental wave. The absorption coefficient of the laser light with respect to the silicon film is very low, and it is difficult to crystallize an amorphous silicon film which is one of the semiconductor films. However, this laser beam can be converted to a shorter wavelength by using a nonlinear optical element such as LBO, CLBO, BBO, CBO, and the second harmonic (532 nm) and third harmonic ( 355 nm), fourth harmonic (266 nm), and fifth harmonic (213 nm). Since these harmonics have a higher absorption coefficient than the amorphous silicon film, they can be used for crystallization of the amorphous silicon film.

  According to said invention, there exists an effect that the cost reduction and structure simplification of an optical annealing apparatus can be aimed at with respect to the general laser light source used for laser annealing.

  In order to solve the above problems, the optical annealing apparatus of the present invention is characterized in that the intensity of the film modification light is larger than the intensity of the inspection light.

  According to the above invention, since the intensity of the film modification light is larger than the intensity of the inspection light, there is an effect that it is possible to obtain film modification light suitable for crystallinity modification requiring a high intensity. In addition, the semiconductor film can be prevented from being modified by the inspection light.

  In order to solve the above problems, the optical annealing apparatus of the present invention is characterized in that the response content is at least one of scattered light, reflected light, diffracted light, and transmitted light of the inspection light with respect to the film. It is characterized by intensity or intensity distribution.

  According to the above invention, the response content obtained from the film when the film is irradiated with the inspection light is at least one of the scattered light, reflected light, diffracted light, and transmitted light of the inspection light with respect to the film. Since there are two intensities or intensity distributions, there is an effect that inspection light obtained from a light source common to the film modification light can be used for general evaluation items of the film modification state.

  As described above, the method for manufacturing a semiconductor film of the present invention includes a step of dividing light emitted from a light source into two or more beams, and at least one of the two or more beams is subjected to film modification light. A step of modifying the crystallinity of the semiconductor film by irradiating the semiconductor film formed on the substrate, and inspecting at least one of the two or more beams other than the film modifying light. Irradiating the semiconductor film as light, and detecting the response content of the inspection light irradiation obtained from the semiconductor film, thereby evaluating a modified state of the semiconductor film.

  As described above, there is an effect that it is possible to realize a method of manufacturing a semiconductor film that can perform light annealing and evaluation of film quality obtained by the light annealing, and can reduce the cost of the apparatus and simplify the configuration.

  As described above, the optical annealing apparatus according to the present invention includes a light source, an optical system that divides the light emitted from the light source into two or more beams, and at least one of the two or more beams as a film. An optical system for modifying the film by irradiating a film formed on the substrate as modified light, and at least one of the two or more beams other than the film modified light as inspection light An optical system for irradiating the film; and a component for detecting a response content of the inspection light irradiation obtained from the film.

  As described above, there is an effect that it is possible to realize an optical annealing apparatus that is used for optical annealing and evaluation of film quality obtained by the optical annealing, and that can reduce the cost of the apparatus and simplify the configuration.

  The embodiment of the present invention will be described with reference to FIGS. 1 and 2 as follows.

  FIG. 1 shows the configuration of a laser annealing apparatus (optical annealing apparatus) 1 according to this embodiment.

  The laser annealing apparatus 1 includes a laser oscillator 2, a beam splitter 3, an attenuator 4, a beam shaping optical system 5, a condensing lens 6, a substrate scanning stage 8, a processing chamber 9, a vacuum pump 10, an attenuator 11, a mirror 12, and a condensing lens. 13, a filter 14, a detector 15, and a shielding chamber 16.

A laser oscillator (laser light source) 2 includes a light source for supplying film-modifying light, which is light for crystallization of a semiconductor thin film formed on a substrate, and inspection light for inspecting the crystallized semiconductor thin film. It also serves as both a light source that supplies Here, the annealing target in which the semiconductor thin film is formed on the substrate is referred to as a substrate 7 to be processed. As a laser beam (hereinafter also referred to as a laser beam), it is assumed that a continuous wave (CW) LD (laser diode) pumped Nd: YVO ₄ laser second harmonic solid-state laser (wavelength λ = 532 nm) is used. However, it is desirable to use a laser having a wavelength range of 200 nm to 700 nm which absorbs amorphous semiconductor or polysilicon semiconductor thin film. More specifically, Nd: YAG laser, Nd: YVO ₄ laser, Nd: YLF laser second harmonic, third harmonic, fourth harmonic, and the like can be applied. Considering the stability, the second harmonic of the LD-pumped Nd: YAG laser (wavelength λ = 532 nm) or the second harmonic of the Nd: YVO ₄ laser is most desirable.

In general, the laser light source can be a solid state laser, a semiconductor laser, or a gas laser. Examples of the solid laser include a YAG laser, a YVO ₄ laser, a YLF laser, a YAlO ₃ laser, a glass laser, a ruby laser, an alexandrite laser, and a titanium sapphire laser. The gas laser includes an excimer laser, an Ar laser, and a Kr laser. Etc. Further, as the active species having a laser action, for example, trivalent ions (Cr ³⁺ , Nd ³⁺ , Yb ³⁺ , Tm ³⁺ , Ho ³⁺ , Er ³⁺ , Ti ³⁺ ) can be used. In addition, a semiconductor laser, a disk laser, or a fiber laser can be used. In the above configuration, it is preferable that the laser light is converted into a harmonic by a nonlinear optical element. For example, a YAG laser is known to emit laser light having a wavelength of 1064 nm as a fundamental wave. The absorption coefficient of the laser light with respect to the silicon film is very low, and it is difficult to crystallize an amorphous silicon film which is one of the semiconductor films. However, this laser beam can be converted to a shorter wavelength by using a nonlinear optical element such as LBO, CLBO, BBO, CBO, and the second harmonic (532 nm) and third harmonic ( 355 nm), fourth harmonic (266 nm), and fifth harmonic (213 nm). Since these harmonics have a higher absorption coefficient than the amorphous silicon film, they can be used for crystallization of the amorphous silicon film.

  The laser oscillation method may be a continuous oscillation type or a pulse oscillation type. Laser beam irradiation conditions, for example, frequency, power density, energy density, beam profile, and the like are appropriately adjusted in consideration of material properties and thickness.

  An optical system O1 for crystallization is provided on the optical path from the laser oscillator 2 to the surface of the semiconductor thin film of the substrate 7 to be processed placed on the substrate scanning stage 8, and is on the laser oscillator 2 side. The beam splitter 3, the attenuator 4, the beam shaping optical system 5, and the condensing lens are arranged in order.

  The beam splitter 3 splits the laser light L emitted from the laser oscillator 2 into two beams, a crystallization beam (film modification light) L1 and an inspection beam (inspection light) L2. System). The beam splitter 3 may be anything such as a parallel plane type, a wedge type, or a cube type as long as the beam can be divided into two with good reproducibility. When dividing, the beam is divided so that the crystallization beam L1 is stronger. This is because the crystallization beam L1 is strengthened to perform more efficient crystallization, and the inspection beam L2 is too strong to modify the film upon irradiation with inspection light. When the laser used for crystallization is a CW laser, the CW laser may be pulse-modulated as necessary.

  The attenuator 4 attenuates the intensity of the crystallization beam L1 to a value suitable for crystallization. The beam shaping optical system 5 shapes the beam shape of the crystallization beam L1 that has passed through the attenuator 4. The beam shaping optical system 5 shapes the beam by a combination of a beam expander, a homogenizer, a diffractive optical element, a Powell lens, an fθ lens, and the like. The condensing lens 6 condenses the crystallization beam L1 that has passed through the beam shaping optical system 5 on the surface of the substrate 7 to be processed. The condensing lens 6 may be a cylindrical lens or the like, but it is possible to shape the beam by combining two cylindrical lenses and to omit the beam shaping optical system. The attenuator 4, the beam shaping optical system 5, and the condenser lens constitute a modified optical system O1 that is an optical system for performing crystallization. By combining these, the shape of the crystallization beam L1 is shaped into a desired shape such as a linear shape, an elliptical shape, or a rectangular shape, and crystallization is performed.

  The substrate scanning stage 8 is an xy stage, and the beam irradiation position of the substrate 7 to be processed can be changed by moving in the xy direction. Alternatively, the position of the substrate scanning stage 8 may be fixed so that the beam L emitted from the laser oscillator 2 can scan the surface of the substrate 7 to be processed. The substrate scanning stage 8 is provided in the processing chamber 9. The substrate scanning stage 8 can heat the substrate, and the substrate temperature when the substrate 7 to be processed is irradiated with laser light is about room temperature to about 500 ° C. The processing chamber 9 can be evacuated by a vacuum pump 10, whereby an atmosphere in the processing chamber 9 at the time of laser irradiation of the substrate 7 to be processed is changed to an inert gas such as nitrogen, helium, neon, argon, or krypton. It can be an atmosphere, a hydrogen atmosphere, a vacuum, or an air atmosphere.

  The optical path of the inspection beam L2 generated by being split by the beam splitter 3 passes through the attenuator 11, the mirror 12, and the condenser lens 13 in this order, and is incident on the surface of the substrate to be processed 7 in an oblique direction. Then, the inspection beam L2 reflected by the surface of the substrate 7 to be processed includes a reflected light path that passes through the filter 14 and reaches the detector 15. These optical systems on the incident optical path and the reflected optical path constitute an inspection optical system O2 for inspecting the crystallization state, that is, the modified state of the semiconductor thin film.

  The attenuator 11 attenuates the inspection beam L2 to an intensity suitable for inspection. The mirror 12 reflects the inspection beam L <b> 2 that has passed through the attenuator 11, and changes the course so as to face the substrate 7 to be processed. The condensing lens 13 is provided as necessary, and condenses the inspection L2 reflected by the mirror 12 on the surface of the substrate 7 to be irradiated with the crystallization beam L1. The filter 14 removes noise light and narrows down the wavelength used by the detector 15 so that the inspection beam L2 reflected from the substrate 7 to be processed can be accurately detected. .

  The detector 15 is a component that receives the inspection beam L2 that has passed through the filter 14 and detects the response content from the substrate 7 to be processed with respect to the irradiation of the inspection beam L2. The response content is, for example, at least one intensity or intensity distribution of scattered light, reflected light, diffracted light, and transmitted light of the inspection beam L2 with respect to the substrate 7 to be processed. When detecting Raman scattered light, the scattered light is passed through a filter such as a notch filter or an edge filter in order to separate the scattered light into Rayleigh scattered light having the same wavelength as the incident light and Raman scattered light having a different wavelength. Spectrally detect the detected light. By analyzing this Raman scattering spectrum, the quality of the crystal can be determined. Further, the detector 15 or an analyzer connected to the detector 15 detects the response content to evaluate the modified state of the semiconductor thin film.

  Depending on the adjustment of the split ratio of the beam splitter 3 or the adjustment of the output of the laser oscillator, at least one of the attenuator 4 and the attenuator 11 may be omitted. Further, in the inspection beam L2, similarly to the crystallization beam L1, a beam shaping optical system is inserted to form a linear or rectangular shape instead of a beam spot, so that the crystallinity of a certain area is obtained. It is also possible to detect the distribution of.

  The shielding chamber 16 is a chamber provided with a shielding plate made of metal or the like surrounding the outer periphery of the laser annealing apparatus 1 described above. The shielding plate prevents the laser light in the laser annealing apparatus 1 from leaking to the outside. Furthermore, it is desirable to provide a vacuum chamber in the laser annealing apparatus 1 so that the inside of the chamber can be evacuated, but the inside of the laser annealing apparatus 1 may be set to normal pressure. Further, it is desirable that the chamber is provided with a chemical filter, a particle filter, etc. so as not to contaminate the atmosphere.

  Each of the crystallization beam L1 and the inspection beam L2 may be further divided so that a plurality of regions can be irradiated. That is, the beam L emitted from the laser device 1 may be divided into two or more beams. Some of the beams obtained by the division may be used as other than both the crystallization beam L1 and the inspection beam L2. In addition, the processing time can be shortened by using a plurality of laser oscillators. When a plurality of laser oscillators are used, a plurality of laser beams may be incident on one shaping optical system.

  The substrate 7 to be processed is a substrate in which a semiconductor thin film is formed on a substrate on which a base protective film is formed. Examples of the substrate include quartz, glass, plastic, silicon wafer, metal, and ceramic. Examples of the base protective film include a film made of an insulating material such as a silicon oxide film and a silicon nitride film, and may be a laminated film thereof. This base protective film is a film for preventing impurity diffusion from the substrate, and may be omitted if there is no fear of such a problem. The thickness of the base protective film is about 100 nm to 2 μm as a whole, including the case of the laminated film. A base protective film is formed on the substrate by LPCVD, plasma CVD, sputtering, or the like, and then a non-single-crystal semiconductor thin film is formed to a thickness of about 30 nm to 250 nm, for example, 50 nm by LPCVD, plasma CVD, sputtering, or the like. Form to thickness.

  Non-single-crystal semiconductor thin films include amorphous silicon, polycrystalline silicon, amorphous germanium, polycrystalline germanium, amorphous silicon / germanium, polycrystalline silicon / germanium, amorphous silicon / carbide, polycrystalline silicon / carbide Etc. In the case where the non-single-crystal semiconductor thin film is formed by a plasma CVD method or the like, dehydrogenation treatment at about 400 ° C. to 600 ° C. may be performed thereafter. In addition, a silicon oxide film, a silicon nitride film, or a stacked film of about 2 nm to 100 nm may be formed on the non-single-crystal semiconductor thin film. Subsequently, island-like regions are formed by photolithography as necessary. This step can be omitted.

Subsequently, the non-single-crystal semiconductor thin film thus formed is crystallized. Hereinafter, an example in which the second harmonic (wavelength: 532 nm) of a CW Nd: YVO ₄ laser is used as the laser beam will be described. To do. The crystallization beam L1 is shaped into a linear shape of, for example, 500 μm × 20 μm by the beam shaping optical system 5, and the beam short axis direction is set as the scanning direction. The line scanning speed can be about 10 cm to 100 m per second, but here it is fixed at 50 cm / s. The laser power is 10 W, and the substrate size is 730 × 920 mm ² . The scanning may be performed by scanning the laser beam with the substrate position fixed, or by moving the stage on which the substrate is placed. However, the crystallization beam L1 and the inspection beam L2 are applied to the non-single crystal semiconductor thin film of the substrate 7 to be processed. In consideration of irradiating the same spot on the surface, in the present invention, it is desirable to move the substrate scanning stage 8 side.

  The detector 15 has an intensity or intensity distribution of at least one of scattered light, reflected light, diffracted light, and transmitted light of the inspection beam L2 irradiated obliquely onto the surface of the non-single crystal semiconductor thin film. To detect. The scattered light can also include Raman scattered light.

  Note that when the substrate 7 to be processed is transparent, the non-single-crystal semiconductor thin film may be irradiated with laser from the back side of the substrate. Further, laser scanning may be performed a plurality of times. Further, the entire surface may be crystal-modified while the crystallization beam L1 is overlapped little by little, or only a necessary portion may be crystal-modified.

  By irradiation with the CW laser, the non-single crystal semiconductor thin film is polycrystallized to obtain a polycrystalline semiconductor thin film. The crystal in the polycrystalline semiconductor thin film is 10 to 100 times larger than the crystal obtained by pulsed irradiation with a conventional excimer laser, becomes a streamline crystal elongated in the laser scanning direction, and has a crystal grain size of 5 μm. This can be done.

  Next, with reference to FIG. 2, a process for forming a TFT from the polycrystalline semiconductor thin film formed in this way will be described.

  The substrate 7 to be processed after the crystallization is finished has a configuration in which a substrate 21, a base protective film 22, and an island-shaped polycrystalline semiconductor thin film 23 are laminated in this order, as shown in FIG. The polycrystalline semiconductor thin film 23 is further patterned into a desired TFT shape. At this time, it is preferable that the major axis direction of the crystal in the polycrystalline semiconductor is the current flowing direction.

Next, as shown in FIG. 2B, a gate insulating film 24, for example, a SiO ₂ film is formed on the entire upper surface of the substrate to a thickness of about 200 nm or less. The thin film 23 is covered. Thereafter, a conductive film 25, for example, an aluminum film is formed on the gate insulating film 24 to a thickness of 300 nm. Then, a resist pattern 26 having a desired gate electrode shape is formed on the conductive film 25 using a photoresist.

  Next, as shown in FIG. 2C, the conductive film 25 is etched using the resist pattern 26 as a mask to form a gate electrode 25a. Thereafter, the resist pattern 26 is removed.

  Next, as shown in FIG. 2D, the gate insulating film 24 is patterned using the gate electrode 25a as a mask, and the portion of the gate insulating film 24 other than under the gate electrode 25a is removed.

Thereafter, as shown in FIG. 2E, the gate electrode 25a is used as a mask to the polycrystalline semiconductor thin film 23, for example, P (phosphorus) is used as an n-type impurity, the acceleration energy is 10 keV, and the dose is 4 × 10 ¹³ cm. Source / drain regions 23a and 23a are formed by ion doping under the condition of ^-2 . Further, the impurity in the source / drain region 23a is activated by thermal annealing at 400 ° C. to 600 ° C., lamp annealing, laser annealing or the like.

  Next, as shown in FIG. 2F, a silicon oxide film or a laminated film of a silicon oxide film and a silicon nitride film is formed as an interlayer insulating film 27 on the entire upper surface of the substrate by a CVD method to 200 nm to 900 nm. The thickness is formed.

  Next, as shown in FIG. 2 (g), after forming contact holes 28, 28 communicating with the source / drain regions 23a, 23a in the interlayer insulating film 27, a metal film 29 is formed on the entire upper surface of the substrate by sputtering. Form.

  Thereafter, as shown in FIG. 2H, the metal film 29 is patterned by photolithography to form source / drain electrodes 29a and 29a. In this way, the TFT 30 is completed.

  According to the present embodiment, the light emitted from the light source is divided into two or more beams, and at least one of the beams is irradiated onto the semiconductor film formed on the substrate as film-modifying light. On the other hand, the modified state of the semiconductor film is evaluated by detecting the response content by irradiating the semiconductor film with at least one beam other than the film modifying light as the inspection light.

  Therefore, since the film modification light and the inspection light are generated by the same light source, it is not necessary to separately provide the light source for the film modification light and the inspection light as in the conventional case. By performing crystallization and inspection in the same device, the manufacturing cost of active matrix display devices such as thin film transistors, liquid crystal display devices, and organic EL devices can be reduced, manufacturing / inspection time can be reduced, and yield can be improved. be able to.

  As described above, it is possible to realize a method of manufacturing a semiconductor film that can perform light annealing and evaluation of film quality obtained by the light annealing, and can reduce the cost of the apparatus and simplify the configuration.

  Further, according to the present embodiment, the light source (laser oscillator 2) and the optical that divides the light (beam L) emitted from the light source into two or more beams (crystallization beam L1 and inspection beam L2). A splitting optical system (beam splitter 3) as a system and at least one of the two or more beams as film-modifying light (crystallization beam L1) is used as a substrate (substrate 21 or base protective film 22). A modified optical system (modified optical system O1) which is an optical system for modifying the film by irradiating a film (non-single crystal semiconductor thin film) formed on the formed substrate 21), and the two or more An inspection optical system (inspection optical system O2) that is an optical system for irradiating the film with inspection light (inspection beam L2) as at least one beam other than the film modification light. The response content of the obtained inspection light irradiation Light annealing apparatus that includes a component (detector 15) to output (laser annealing apparatus 1) is provided.

  Therefore, it is possible to realize a light annealing apparatus that is used for light annealing and evaluation of the film quality obtained by the light annealing and can reduce the cost of the apparatus and simplify the configuration.

  As the light source, a lamp light source such as a flash lamp used for lamp annealing can also be used. When it is desired to narrow down the lamp light beam, a collimation process may be applied.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims. That is, embodiments obtained by combining technical means appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

  The present invention relates to, for example, an image display device such as a liquid crystal display or an organic EL, a system on panel in which a display device, a drive circuit, a memory, a CPU, etc. are integrated on a substrate, a crystal used for an image sensor, etc. It is suitable for manufacturing a conductive semiconductor thin film.

1, showing an embodiment of the present invention, is a block diagram showing a configuration of a light annealing apparatus. FIG. (A) thru | or (h) is a flowchart which shows the process of manufacturing TFT using the semiconductor film which modified crystallinity with the optical annealing apparatus of FIG. It is a block diagram which shows a prior art and shows the structure of a laser annealing apparatus.

Explanation of symbols

1 Laser annealing equipment (light annealing equipment)
2 Laser oscillator (light source, laser light source)
15 Detector (parts)
21 Substrate 23 Polycrystalline semiconductor thin film ((manufactured) semiconductor film)
O1 modified optical system O2 inspection optical system

Claims (12)

Dividing the light emitted from the light source into two or more beams;
Modifying the crystallinity of the semiconductor film by irradiating the semiconductor film formed on the substrate with at least one of the two or more beams as film modifying light;
Irradiating the semiconductor film with at least one of the two or more beams other than the film-modifying light as inspection light, and detecting response contents of irradiation of the inspection light obtained from the semiconductor film And a step of evaluating a modified state of the semiconductor film.   The method of manufacturing a semiconductor film according to claim 1, wherein the semiconductor film is a non-single crystal semiconductor film.   The non-single crystal semiconductor film is amorphous silicon, polycrystalline silicon, amorphous germanium, polycrystalline germanium, amorphous silicon / germanium, polycrystalline silicon / germanium, amorphous silicon / carbide, or polycrystalline 3. The method of manufacturing a semiconductor film according to claim 2, wherein the semiconductor film is silicon carbide.   4. The method of manufacturing a semiconductor film according to claim 1, wherein the light source is a laser light source.   5. The method of manufacturing a semiconductor film according to claim 1, wherein the intensity of the film modification light is greater than the intensity of the inspection light.   The response content is intensity or intensity distribution of at least one of scattered light, reflected light, diffracted light, and transmitted light of the inspection light with respect to the semiconductor film. 6. The method for producing a semiconductor film according to any one of 5 to 5. A light source;
A splitting optical system that is an optical system that splits the light emitted from the light source into two or more beams;
A modified optical system that is an optical system that modifies the film by irradiating the film formed on the substrate with at least one of the two or more beams as film-modified light;
An inspection optical system that is an optical system that irradiates the film with at least one of the two or more beams other than the film modification light as inspection light; and
And a part for detecting the response content of the inspection light irradiation obtained from the film.   The optical annealing apparatus according to claim 7, wherein the light source is a laser light source.   9. The optical annealing apparatus according to claim 8, wherein the laser light source is a continuous wave or pulsed laser, a solid-state laser, a semiconductor laser, or a gas laser. The laser light source is a continuous wave or pulsed wave YAG laser, YVO ₄ laser, YLF laser, YAlO ₃ laser, glass laser, ruby laser, alexandrite laser, titanium sapphire laser, excimer laser, Ar laser, or Kr laser. The optical annealing apparatus according to claim 8, wherein the optical annealing apparatus is provided.   The optical annealing apparatus according to claim 7, wherein the intensity of the film modification light is greater than the intensity of the inspection light.   12. The response content is at least one intensity or intensity distribution of scattered light, reflected light, diffracted light, and transmitted light of the inspection light with respect to the film. The optical annealing apparatus according to any one of the above.

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