JP6450932B2 - Plasma processing apparatus and method - Google Patents

Description

  The present invention can be applied to a thermal plasma treatment in which a substrate is treated by irradiating the substrate with thermal plasma using an inductively coupled plasma torch, or a substrate by irradiating the substrate with plasma by a reactive gas or plasma and a reactive gas flow simultaneously. The present invention relates to a plasma processing apparatus and method such as plasma processing for processing a material.

  Conventionally, semiconductor thin films such as polycrystalline silicon (poly-Si) are widely used for thin film transistors (TFTs) and solar cells. As a method of forming this, there is a method of crystallizing an amorphous silicon film by irradiating a laser beam. The laser process can also be applied to activation of impurity atoms introduced into a semiconductor substrate by ion implantation or plasma doping.

  However, this laser annealing technique has problems such as the occurrence of seams, and requires very expensive equipment.

  Therefore, techniques for performing heat treatment seamlessly and inexpensively by generating a long thermal plasma and scanning only in one direction have been studied (for example, Patent Documents 1 to 3 and Non-Patent Document 1). reference).

  In addition, a technique for heat-treating the surface in a lump using a flash lamp has been studied, and the substrate is preliminarily heated to devise to prevent destruction of the substrate due to thermal shock or the like (for example, (See Patent Document 4).

JP 2013-120633 A JP 2013-120684 A JP 2013-120585 A JP 2008-28084 A

T.A. Okumura and H.M. Kawaura, Jpn. J. et al. Appl. Phys. 52 (2013) 05EE01.

  However, when the method using the annular chamber described in Patent Documents 1 to 3 and Non-Patent Document 1 by the present inventors and the preheating using the hot plate described in Patent Document 4 are combined, There was a problem that the temperature was difficult to rise. Compared to the energy density of the flash lamp, the plasma torch has a lower energy density, and in the configuration where the substrate is in contact with the hot plate, the heat capacity of the object to be heated is large. End up.

  In order to reduce the heat capacity of the object to be heated, it is necessary to support the substrate only at the periphery and to make most of it non-contact. As a non-contact preheating method, for example, a method of irradiating the substrate with an infrared lamp or the like can be considered, but when the substrate is scanned with respect to the plasma torch, it is necessary to scan the lamp and the substrate integrally. The device configuration becomes extremely complicated.

  When scanning the torch, it is necessary to scan the high-frequency system, the gas system, and the refrigerant system together, which greatly complicates the apparatus configuration. In order to perform preheating with a lamp with a relatively simple configuration, it is preferable to preheat the base material with a stationary lamp, scan only the base material, and heat-treat with a plasma torch. However, it is necessary to prepare a lamp in addition to the plasma torch, and the apparatus configuration is more complicated than the configuration in which the plasma torch itself preheats.

  As a method of preheating with the plasma torch itself, it is conceivable to irradiate the plasma torch by scanning the substrate a plurality of times. Each time scanning is performed, the ultimate temperature can be gradually increased by giving changes such as increasing the high-frequency power input to the plasma torch, decreasing the scanning speed, and reducing the distance between the plasma torch and the substrate.

  However, if there is temperature unevenness (non-uniformity) in the long longitudinal direction (perpendicular to the scanning direction), the temperature unevenness is emphasized by multiple scans, and in the main heating (scanning to reach the maximum temperature) There is a problem that uneven temperature becomes large.

  This is because the main cause of the long temperature unevenness in the longitudinal direction is considered to be the unevenness of the surface facing the substrate in the opening of the plasma torch. That is, as the distance between the surface of the opening of the plasma torch facing the base material and the base material is shorter, the ultimate temperature of the base material becomes higher.

  In addition, even when there is no temperature unevenness due to the plasma torch itself, the interval time when scanning a plurality of times (for example, the time elapsed between the first heating and the second heating) depends on the position of the substrate. If they are different, unevenness occurs in the maximum temperature reached by the substrate.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a plasma processing apparatus and method capable of realizing excellent uniformity when heat-treating a substrate by a plurality of scans.

The plasma processing apparatus of the first invention of the present application is characterized by having the following configuration.
[1] A long and annular chamber surrounded by a dielectric member, a slit-shaped opening communicating with the chamber, a gas supply pipe for introducing gas into the chamber, and a vicinity of the chamber. Inductively coupled plasma torch with a coil.
[2] A high-frequency power source connected to the coil.
[3] A substrate mounting table that holds the substrate facing the opening.
[4] The longitudinal direction of the chamber and the longitudinal direction of the opening are arranged in parallel, and the chamber and the base material can be relatively moved in a direction perpendicular to the longitudinal direction of the opening. Moving mechanism.
[5] A substrate rotation mechanism for rotating the substrate at a position where the substrate is separated from the chamber.

  With such a configuration, excellent uniformity can be realized when the substrate is heat-treated by a plurality of scans.

  In the plasma processing apparatus of the first invention of the present application, it is preferable that the chamber is preferably arranged perpendicular to a plane formed by the substrate mounting table.

  With such a configuration, a plasma processing apparatus having a simpler configuration can be realized.

  In addition, it is preferable to provide a base material separation mechanism for separating the base material from the base material mounting table.

  With such a configuration, it is possible to prevent generation of particles that may be generated due to friction between the base material and the base material mounting table.

  In this case, it is more preferable that the holding mechanism for holding the substrate is the same in the substrate rotating mechanism and the substrate separating mechanism.

  With such a configuration, a device with a simple configuration can be realized.

  Moreover, it is preferable that the substrate mounting table is configured to hold the substrate perpendicular to the ground.

  With such a configuration, the distance between the base material and the chamber is not longer in the longitudinal direction because the base material is deformed due to the bending due to its own weight as compared with the case where the base material is held horizontally with respect to the ground. Since the degree of uniformity is improved, more uniform processing can be realized.

The plasma processing method of the second invention of the present application has the following steps.
[1] While supplying gas into a long and annular chamber surrounded by a dielectric, it has a long shape in a direction parallel to the longitudinal direction of the chamber, and has a slit shape communicating with the chamber. Gas is ejected from the opening toward the substrate.
[2] Supplying high-frequency power to the coil in a state where the coil is disposed in the vicinity of the chamber, thereby generating a high-frequency electromagnetic field in the chamber to generate plasma.
[3] An inductively coupled plasma torch is used to heat-treat the surface of the base material by moving the chamber and the base material in a direction perpendicular to the longitudinal direction of the opening.
[4] The heat treatment is continuously performed a plurality of times, and the substrate is rotated at a position away from the chamber at a timing between the heat treatments.

  With such a configuration, excellent uniformity can be realized when the substrate is heat-treated by a plurality of scans.

  ADVANTAGE OF THE INVENTION According to this invention, the plasma processing apparatus and method which can implement | achieve the outstanding uniformity when heat-processing a base material by multiple times of scanning can be provided.

Sectional drawing which shows the structure of the plasma processing apparatus in Embodiment 1 of this invention The perspective view which shows the structure of the plasma processing apparatus in Embodiment 1 of this invention. Sectional drawing which shows the structure of the plasma processing apparatus in Embodiment 1 of this invention The figure which shows the characteristic of the plasma processing in Embodiment 1 of this invention The figure which shows the characteristic of the plasma processing in the prior art used for the comparison in Embodiment 1 of this invention The figure which shows the characteristic of the plasma processing in Embodiment 1 of this invention

  Hereinafter, a plasma processing apparatus according to an embodiment of the present invention will be described with reference to the drawings.

(Embodiment 1)
Hereinafter, Embodiment 1 of the present invention will be described with reference to FIGS.

  FIG. 1A shows the configuration of the plasma processing apparatus according to Embodiment 1 of the present invention, and is a cross-sectional view taken along a plane perpendicular to the longitudinal direction of the inductively coupled plasma torch unit T. FIG. FIG. 1B is a cross-sectional view of the inductively coupled plasma torch unit cut along a plane parallel to the longitudinal direction and perpendicular to the substrate.

  1A is a cross-sectional view taken along the broken line in FIG. 1B, FIG. 1B is a cross-sectional view taken along the broken line in FIG. 1A, and FIG. 2 is the guide shown in FIG. FIG. 4 is an assembly configuration diagram of a combined plasma torch unit, in which perspective views of parts (part) are arranged.

  1 and 2, a thin film 2 is formed on a substrate 1. In the inductively coupled plasma torch unit T, the coil 3 made of a conductor is disposed in the vicinity of the first ceramic block 4 and the second ceramic block 5 made of a dielectric. The coil 3 is formed by bonding a copper tube having a circular cross section to a copper block having a rectangular cross section. A long chamber 7 made of a dielectric material is defined by a space surrounded by the first ceramic block 4, the second ceramic block 5, and the thin film 2 forming the surface of the substrate 1.

  The long chamber 7 is provided along a surface perpendicular to the surface formed by the substrate 1. In addition, the central axis of the coil 3 is configured to be parallel to the substrate 1 and to be perpendicular to a plane including the long chamber 7. That is, the surface formed by one turn of the coil 3 is provided along a plane perpendicular to the surface formed by the base material and along a plane including the long chamber 7.

  The inductively coupled plasma torch unit T is entirely surrounded by a shield member (not shown) made of a grounded conductor, which can effectively prevent high-frequency leakage (noise) and effectively prevent undesirable abnormal discharge. Can be prevented.

  The long chamber 7 is surrounded by one plane of the first ceramic block 4 and a groove provided in the second ceramic block 5. Further, two dielectric blocks as these dielectric members are bonded together. That is, the long chamber 7 has a configuration in which a portion other than the opening 8 is surrounded by a dielectric.

  The long chamber 7 is annular. The term “annular” as used herein means a shape that forms a continuous string of strings, and is not limited to a circle. In the present embodiment, a long chamber 7 having a rectangular shape (a continuous closed string-like shape formed by connecting two straight lines having two long sides and two straight lines forming two short sides at both ends). Is illustrated. The plasma P generated in the long chamber 7 comes into contact with the thin film 2 forming the surface of the substrate 1 at the long and linear opening 8 in the long chamber 7. Further, the longitudinal direction of the long chamber 7 and the longitudinal direction of the opening 8 are arranged in parallel.

  A plasma gas manifold 9 is provided inside the second ceramic block 5. The gas supplied from the plasma gas supply pipe 10 to the plasma gas manifold 9 is introduced into the long chamber 7 through a plasma gas supply hole 11 (through hole) as a gas introduction portion provided in the second ceramic block 5. Is done. With such a configuration, a uniform gas flow in the longitudinal direction can be easily realized. The flow rate of the gas introduced into the plasma gas supply pipe 10 is controlled by providing a flow rate control device such as a mass flow controller upstream thereof.

  The plasma gas supply hole 11 is a long slit, but a plurality of round holes may be provided in the longitudinal direction.

  The base material 1 is mounted on the base material holder 12 as a base material mounting base. The base material holder 12 is provided with a through hole that is substantially similar to the outer shape of the base material 1 and slightly smaller, and a counterbore portion that is substantially similar to the outer shape of the base material 1 and slightly larger. By placing on the spot facing portion, the outer portion of the face facing the inductively coupled plasma torch unit T of the base material holder 12 and the surface of the base material 1 form substantially the same surface. Thus, the depth of the spot facing portion is substantially equal to the thickness of the substrate 1.

  With such a configuration, when the base material holder 12 is moved relative to the inductively coupled plasma torch unit T, an annular ring that is a space for generating plasma regardless of the position of the base material holder 12 is used. The shape of the long chamber 7 is substantially constant. That is, it is possible to suppress the fluctuation of the plasma accompanying the movement. Moreover, it is comprised so that the heat capacity of a to-be-heated material may become small by supporting a base material only by a periphery and making most the non-contact.

  The inside of the copper pipe in the coil 3 is a refrigerant flow path. Further, the copper block bonded to the outside is bonded to the first ceramic block 4 or the second ceramic block 5 with an adhesive (not shown). Thus, by making the cross section of the coil 3 a rectangular parallelepiped, the adhesive between the first ceramic block 4 or the second ceramic block 5 can be made as thin as possible, and thus good heat conduction is ensured.

  Therefore, the coil 3, the first ceramic block 4, and the second ceramic block 5 can be cooled by allowing a coolant such as water to flow through the copper pipe constituting the coil 3.

  The coils 3 are arranged one by one on the outside of the first ceramic block 4 and on the outside of the second ceramic block 5 and connected in series at a position away from the long chamber 7 to apply high-frequency power. At this time, the directions of the high-frequency electromagnetic fields generated in the long chamber 7 are made equal to each other. The coil 3 can function with only one of these two, but when the two are provided with the long chamber 7 interposed therebetween as in the present embodiment, the coil 3 is generated in the long chamber 7. There is an advantage that the strength of the electromagnetic field can be increased.

  A rectangular linear opening 8 is provided, and the substrate 1 (or the thin film 2 on the substrate 1) is disposed to face the opening 8. By supplying high-frequency power of, for example, 13.56 MHz from the high-frequency power source (not shown) to the coil 3 while supplying gas into the long chamber 7 and ejecting gas from the opening 8 in advance, Plasma P is generated in the chamber 7, and then the substrate 1 is moved to the vicinity of the inductively coupled plasma torch unit T, and the plasma in the vicinity of the opening 8 is exposed to the thin film 2 that forms the surface of the substrate 1. Thus, the thin film 2 on the substrate 1 can be plasma-treated.

  The base material 1 is processed by relatively moving the long chamber 7 and the base material 1 in a direction perpendicular to the longitudinal direction of the opening 8. That is, the inductively coupled plasma torch unit T or the substrate 1 is moved in the left-right direction in FIG. 1A and in the direction perpendicular to the paper surface in FIG.

  Various gases can be used as the gas to be supplied into the long chamber 7. However, considering the stability of the plasma, the ignitability, the life of the member exposed to the plasma, etc., it is desirable that the main gas is mainly an inert gas. Among these, Ar gas is typically used. When plasma is generated only by Ar, the plasma becomes considerably high temperature (10,000 K or more).

As conditions for plasma generation, scanning speed = 50 to 3000 mm / s, plasma gas total flow rate = 1 to 100 SLM, H ₂ concentration in Ar + H ₂ gas = 0 to 10%, high frequency power = about 0.5 to 50 kW Is appropriate. However, among these quantities, the gas flow rate and power are values per 100 mm of the length of the opening 8. This is because it is considered appropriate to input parameters proportional to the length of the opening 8 for parameters such as gas flow rate and electric power.

  Thus, the long chamber and the base material 1 are relatively moved in a direction perpendicular to the longitudinal direction of the opening 8 while the longitudinal direction of the opening 8 and the base material 1 are arranged in parallel. Therefore, as shown in FIG. 1B, the length of the plasma to be generated and the processing length of the substrate 1 can be configured to be substantially equal.

  Moreover, since the part with high temperature, electron density, and active particle density in plasma P is exposed to the surface of the base material 1, a high-speed process or a high temperature process is attained.

  Next, a heat treatment procedure using a method of preheating with the plasma torch itself will be described with reference to FIG. In this method, a plasma torch is irradiated by scanning the substrate a plurality of times.

  First, in FIG. 3A, the base material 1 is placed on the base material holder 12. Then, plasma is ignited in a state (stationary state) in which the first ceramic plate 13 having an upper surface continuous with the upper surface of the substrate holder 12 is disposed directly under the inductively coupled plasma torch unit T. At this time, the first ceramic plate 13 is water-cooled by the first refrigerant pipe 14 bonded thereto so that the first ceramic plate 13 is not thermally damaged.

  Next, the substrate holder 12 is moved from the left to the right in the figure. When a constant speed is reached after sufficient acceleration, the substrate 1 passes directly under the inductively coupled plasma torch unit T as shown in FIG. 3B, and the first heat treatment is performed. Next, the moving mechanism is decelerated, and the second ceramic plate 15 that forms an upper surface continuous with the upper surface of the base material holder 12 is disposed immediately below the inductively coupled plasma torch unit T as shown in FIG. Stop at.

  At this time, the supply of high frequency power can be stopped, but the plasma may be maintained. In the case of proceeding to the next procedure while maintaining the plasma, the second ceramic plate 15 is heated, so that it is water-cooled by the second refrigerant pipe 16 adhered thereto so as not to be thermally damaged.

  Next, as shown in FIG. 3 (d), the base material rotating mechanism for rotating the base material 1 at a position where the base material is away from the inductively coupled plasma torch unit T or the long chamber 7, and the base material The base material 1 is separated from the base material holder 12 by pushing the first push-up turntable 17 that also serves as a base material separation mechanism for separating 1 from the base material holder 12 toward the base material 1. Then, the base material 1 is rotated 120 ° counterclockwise when viewed from the surface of the base material 1 (the surface facing the inductively coupled plasma torch unit T) with the center of the base material 1 as the rotation axis. The first push-up turntable 17 has the same (common) holding mechanism for holding the base material 1, and if the material has a porous structure with good heat insulation, the temperature drop of the base material 1 can be reduced. .

  In addition, as a configuration for improving the heat insulating property, it is possible to use point contact or to support the peripheral portion. An advantage of separating the base material 1 from the base material holder 12 when rotating the base material 1 is that it is possible to prevent generation of particles that may be generated by friction between the base material 1 and the base material holder 12. Conversely, when the generation of particles is allowed, the substrate 1 may be rotated by applying friction to a part of the substrate 1 immediately before the scanning is stopped.

  Then, after placing the base material 1 on the base material holder 12 again, the base material holder 12 is moved from the right to the left in the figure. When a constant speed is reached through sufficient acceleration, the substrate 1 passes directly under the inductively coupled plasma torch unit T as shown in FIG. 3E, and the second heat treatment is performed. At this time, compared with the time of the first heat treatment, by increasing the high frequency power input to the plasma torch, lowering the scanning speed, and bringing the distance between the plasma torch and the substrate closer, the target temperature reached Keep it up. Next, the moving mechanism is decelerated and stops at a position where the first ceramic plate 13 is disposed directly below the inductively coupled plasma torch unit T.

  Next, as shown in FIG. 3 (f), the base material rotating mechanism for rotating the base material 1 at a position where the base material is away from the inductively coupled plasma torch unit T or the long chamber 7, and the base material The substrate 1 is separated from the substrate holder 12 by extruding the second push-up turntable 18 that also serves as a substrate separation mechanism for separating 1 from the substrate holder 12 toward the substrate 1. Then, the base material 1 is rotated 120 ° counterclockwise when viewed from the surface of the base material 1 (the surface facing the inductively coupled plasma torch unit T) with the center of the base material 1 as the rotation axis.

  Next, after placing the base material 1 on the base material holder 12 again, the base material holder 12 is moved from the left to the right in the figure. When a constant speed is reached through sufficient acceleration, the substrate 1 passes directly under the inductively coupled plasma torch unit T as shown in FIG. 3G, and the third heat treatment is performed. At this time, compared to the second heat treatment, the target reached temperature can be achieved by changing the high frequency power input to the plasma torch, lowering the scanning speed, or reducing the distance between the plasma torch and the substrate. Raise it further.

  Next, the moving mechanism is decelerated and stopped at a position where the second ceramic plate 15 is disposed immediately below the inductively coupled plasma torch unit T as shown in FIG. Finally, the base material 1 is separated from the base material holder 12, and the process is terminated.

  The heating characteristics in such a processing procedure will be described with reference to FIG. FIGS. 4A to 4D are plan views of the base material 1 as viewed from the surface of the base material 1 (surface facing the inductively coupled plasma torch unit T), and the base material 1 along the thin arrow. The peak value of the surface temperature is shown in FIG.

  The substrate 1 moves relative to the inductively coupled plasma torch unit T in the left-right direction of FIGS. The shaded portions shown in FIGS. 4A to 4D represent portions where the peak temperature is higher than other portions, and the darker the mesh, the higher the temperature.

  As shown in FIG. 4B, a slight temperature unevenness is caused by the first heat treatment. However, this temperature unevenness is alleviated by heat dissipation or heat diffusion in the surface direction during the second and third heat treatments as shown in FIGS. 4 (c) and 4 (d). That is, the position where the ultimate temperature is locally increased is dispersed. In this way, relatively good uniformity is obtained when the substrate 1 is heat-treated by a plurality of scans.

  For comparison, heating characteristics when the substrate 1 is not rotated will be described with reference to FIG. FIGS. 5A to 5E correspond to FIGS. 4A to 4E, respectively. As shown in FIG. 5B, the temperature unevenness caused by the first heat treatment is heated slightly again at the same position when the second and third heat treatments are performed. ) And (d) as shown in FIG. That is, a processing result inferior in uniformity is obtained as compared with the case where the substrate 1 is rotated.

  In addition, in infrared lamp annealing, etc., heat treatment is generally performed while rotating the base material, but because of the method of heating one side of the base material at a time, such heat uniformity is improved. The measure is effective. However, when scanning using a linear heat source as in the present embodiment, if the heat treatment is performed while rotating, a place where the relative speed is high and a place where the relative speed is high are created depending on the position of the base material 1. The method is not effective (rather, soaking is worse).

  In the present embodiment, it is important to rotate the substrate 1 at a position where the substrate 1 and the heat source are separated (a position where no heating action occurs) after one scan is completed and the substrate 1 is stopped. If heat treatment is performed while the substrate 1 is rotated, it is necessary to rotate the substrate 1 at a speed much faster than the scanning speed. However, since the scanning speed is generally as high as several tens to several hundred mm / s, what is realistic? I can't say that.

  Next, even when there is no temperature unevenness due to the plasma torch itself, the interval time when scanning a plurality of times (for example, the time elapsed between the first heating and the second heating) is the position of the substrate. If the difference is different, there may be a case where unevenness occurs in the maximum temperature of the substrate, which will be described with reference to FIG.

  As described with reference to FIG. 5, a case where the heat treatment is performed twice without rotating the substrate 1 is considered. FIG. 6A shows a temperature change in a portion of the substrate 1 that is heated relatively first (dotted line) and a portion that is heated later (solid line) in the first heat treatment. In this way, the temperature of the portion heated relatively earlier increases to A in the first heat treatment, and the temperature of the portion heated relatively later subsequently increases to A in the same manner. When the second heat treatment is performed by reversing the scanning direction of the substrate 1, the portion heated later in the first heat treatment is first heated when the temperature drops to B, and then the temperature is increased to C. To rise. Next, since the portion heated first in the first heat treatment is subjected to the second heating after the temperature is lowered to D lower than B, the highest temperature reaches E lower than C. In other words, since the interval time for scanning a plurality of times (the time elapsed between the first heating and the second heating) varies depending on the position of the substrate 1, temperature unevenness occurs in the surface.

  This problem can also be solved by rotating the substrate 1. That is, after the first heat treatment is completed over the entire base material 1, the base material 1 is opposed to the surface of the base material 1 (in opposition to the inductively coupled plasma torch unit T with the center of the base material 1 as the rotation axis). Rotate 180 ° clockwise or counterclockwise as viewed from Thereafter, if the second heat treatment is performed by reversing the scanning direction, the interval time (the time elapsed between the first heating and the second heating) when scanning a plurality of times depends on the position of the substrate 1. Therefore, as shown in FIG. 6B, the temperature changes of the portion heated earlier (dotted line) and the portion heated later (solid line) in the first heat treatment are the same. .

  Here, A has the same temperature as A in FIG. 6A, but F satisfies the relationship of B> F> D, and G satisfies the relationship of C> G> E (the first heating and 2). If the second heating interval time is the same).

  The plasma processing apparatus and method described above merely exemplify typical examples of the scope of application of the present invention.

  For example, the substrate holder 12 is scanned with respect to the fixed inductively coupled plasma torch unit T. However, the inductively coupled plasma torch unit T is scanned with respect to the fixed substrate mounting table. May be.

  In this case, it is possible to obtain the same effect as in the first embodiment by rotating the inductively coupled plasma torch unit T, which is a heat source, instead of rotating the base material and changing the scanning direction. . However, the apparatus configuration is simpler in the first embodiment.

  Alternatively, an apparatus configuration including a plurality of inductively coupled plasma torch units T is provided, and temperature unevenness caused by each inductively coupled plasma torch unit T is reduced by performing heat treatment a plurality of times in one scan. Is also possible. However, the configuration of the first embodiment is simpler and less expensive.

  In addition, there is a case where the ultimate temperature is gradually raised by giving changes such as increasing the high frequency power input to the plasma torch, decreasing the scanning speed, and reducing the distance between the plasma torch and the substrate 1 each time scanning is performed. Although illustrated, the heating conditions may be the same. This is because when the heat treatment is performed under the same conditions in the state where heat is stored in the base material 1, the ultimate temperature gradually increases.

  Moreover, although the case where the rotation angle of the base material 1 during the heat treatment is 120 ° is exemplified, it may be appropriately set in consideration of the number of treatments, the tendency of temperature unevenness and the like.

  Further, a non-contact Bernoulli chuck or the like may be used as the substrate holding mechanism in the substrate rotation mechanism and the substrate separation mechanism that separates the substrate 1 from the substrate holder 12. At this time, the Bernoulli chuck itself may be rotated, or the substrate 1 may be rotated by generating a spiral gas flow.

  Further, it is possible to avoid emphasizing temperature unevenness by not moving the base material 1 but by translating the base material 1 in a direction parallel to the longitudinal direction of the long chamber 7. In this case, the apparatus configuration may be simplified, but on the other hand, there is a drawback that the effective heating length in the inductively coupled plasma torch unit T needs to be increased.

  Moreover, in Embodiment 1, although it did not touch especially about the up-down direction (which direction gravity works), the base material holder 12 is comprised so that the base material 1 may be hold | maintained perpendicularly | vertically with respect to the ground. Is desirable.

  This is because the distance between the base material 1 and the long chamber 7 is longer in the longitudinal direction because the base material 1 is deformed by bending due to its own weight as compared with the case where the base material 1 is held horizontally with respect to the ground. This is because the degree of non-uniformity is improved and more uniform processing can be realized. When the base material 1 is held perpendicular to the ground, thermal strain concentrates on the portion located below the base material 1 during the heat treatment, and therefore rotating the base material 1 also suppresses thermal strain accumulation. effective.

  As a method for further reducing temperature unevenness, plasma is oscillated by oscillating at high speed by providing an ultrasonic vibrator in the inductively coupled plasma torch unit T, or by oscillating the supplied gas flow rate. Is also effective.

  In addition, various configurations of the present invention enable high-temperature treatment of the vicinity of the surface of the substrate 1. The present invention can be applied to the crystallization of the TFT semiconductor film and the modification of the semiconductor film for solar cells, which are described in detail in the conventional example. Of course, the protective layer of the plasma display panel is cleaned and degassed, the surface of the dielectric layer made of an aggregate of silica particles is flattened and degassed, semiconductor devices RTP (Rapid Thermal Processing), and various electronic devices It can be applied to various surface treatments such as reflow and plasma doping using a solid impurity source.

  In the description, the term “thermal plasma” is used for simplicity. However, it is difficult to distinguish between thermal plasma and low temperature plasma. For example, Tanaka Yasunori “Non-equilibrium in thermal plasma” plasma nucleus Journal of Fusion Society, Vol. 82, no. 8 (2006) p. As described in 479-483, it is also difficult to classify plasma types based on thermal equilibrium alone.

  The present invention has an object of heat-treating a substrate, and can be applied to a technique for irradiating high-temperature plasma without being bound by terms such as thermal plasma, thermal equilibrium plasma, and high-temperature plasma.

  Moreover, the case where the vicinity of the surface of the substrate is subjected to high-temperature heat treatment uniformly for a very short time has been illustrated in detail, but in the case where the substrate is subjected to plasma treatment by simultaneously irradiating the substrate with plasma or plasma and a reaction gas flow by the reaction gas. However, the present invention is applicable. By mixing the reaction gas with the plasma gas, the plasma by the reaction gas is irradiated onto the substrate, and etching and CVD can be realized.

Alternatively, by using a rare gas or a gas obtained by adding a small amount of H ₂ gas to a rare gas as a plasma gas, a gas containing a reactive gas as a shielding gas is supplied to the periphery of the plasma gas, so that the plasma and the reactive gas flow are changed. At the same time, the substrate can be irradiated to realize plasma processing such as etching, CVD, and doping.

When a gas containing argon as a main component is used as the plasma gas, thermal plasma is generated as exemplified in detail in the embodiment. On the other hand, when a gas containing helium as a main component is used as the plasma gas, a relatively low temperature plasma can be generated. By such a method, processing such as etching and film formation can be performed without heating the substrate too much. Examples of the reactive gas used for etching include a halogen-containing gas such as C _x F _y (x and y are natural numbers), SF _{6, and the} like, and silicon and silicon compounds can be etched. If O ₂ is used as the reaction gas, it is possible to remove organic substances, resist ashing, and form an extremely thin oxide film. The reactive gas used for CVD includes monosilane, disilane, and the like, and silicon or silicon compound can be formed.

Alternatively, a silicon oxide film can be formed by using a mixed gas of O ₂ and an organic gas containing silicon typified by TEOS (Tetraethoxysilane). In addition, various plasma treatments such as a surface treatment for improving water repellency and hydrophilicity are possible. Since the configuration of the present invention is an inductive coupling type, even if a high power density per unit volume is applied, it is difficult to shift to arc discharge, so that a higher density plasma can be generated, resulting in a high reaction rate. As a result, it is possible to efficiently process the entire desired region of the base material in a short time.

  As described above, the present invention can be applied to crystallization of a TFT semiconductor film and modification of a solar cell semiconductor film. Of course, the plasma display panel protective layer is cleaned and degassed, the surface of the dielectric layer consisting of aggregates of silica particles is flattened and degassed, RTP of semiconductor devices, reflow of various electronic devices, solid impurity sources The present invention can be applied to various surface treatments such as plasma doping using. In addition, in plasma processing such as etching, film formation, doping, and surface modification in the manufacture of various electronic devices, etc., this invention is useful for efficiently processing the entire desired region of the substrate in a short time. is there.

T inductively coupled plasma torch unit 1 base material 2 thin film 3 coil 4 first ceramic block 5 second ceramic block 7 long chamber 8 opening 9 plasma gas manifold 10 plasma gas supply pipe 11 plasma gas supply hole

Claims (4)

An inductively coupled plasma torch having a chamber and a slit-shaped opening communicating with the chamber;
A substrate mounting table that holds the substrate facing the opening, and
A moving mechanism capable of relatively moving the chamber and the base material in a direction perpendicular to the longitudinal direction of the opening;
A plasma processing apparatus, comprising: a substrate rotating mechanism that rotates the substrate around an axis perpendicular to the surface of the substrate at a position where the substrate is separated from the chamber. The plasma processing apparatus of Claim 1 provided with the base material separation mechanism which isolate | separates a base material from a base material mounting base. The plasma processing apparatus according to claim 2 , wherein the holding mechanism for holding the substrate is the same in the substrate rotating mechanism and the substrate separating mechanism. While supplying gas into the chamber,
Gas is ejected from the slit-shaped opening communicating with the chamber toward the base material, and high-frequency power is supplied to the coil in a state where the coil is disposed in the vicinity of the chamber. Generate an electromagnetic field to generate plasma,
A plasma processing method using an inductively coupled plasma torch in which the surface of the base material is heat-treated by relatively moving the chamber and the base material in a direction perpendicular to the longitudinal direction of the opening. And
The heat treatment is performed a plurality of times continuously, and at a timing between the plurality of heat treatments, the substrate is rotated around an axis perpendicular to the surface of the substrate at a position away from the chamber. Letting
A plasma processing method characterized by the above.

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