JP2009094329A - Crystallizing apparatus, crystallizing method and device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a crystallizing apparatus which can fully suppress occurrence of an interference fringe on a non-monocrystal semiconductor film without causing an increase in optical system scale according to a simple structure. <P>SOLUTION: The crystallizing apparatus irradiates a light having a predetermined light intensity distribution on the non-monocrystal semiconductor film to generate a crystallizing semiconductor film. The crystallizing apparatus comprises: an illumination system for illuminating an optical modulator through a homegenizer having a plurality of cylindrical lens elements (23ba) arranged along a predetermined direction (y direction); an image forming optical system for forming the predetermined light intensity distribution based on light through the optical modulator; and a plurality of strip-shaped optical members (25) provided in every other position for the plurality of cylindrical lens elements. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a crystallization apparatus, a crystallization method, and a device. In particular, the present invention relates to a crystallization apparatus and a crystallization method for generating a crystallized semiconductor film by irradiating a non-single crystal semiconductor film with laser light having a predetermined light intensity distribution.

  Conventionally, for example, a thin-film-transistor (TFT) used as a switching element for selecting a display pixel of a liquid-crystal display (LCD) is an amorphous silicon or a multi-layer. It is formed using crystalline silicon (poly-Silicon).

  Polycrystalline silicon has higher electron or hole mobility than amorphous silicon. Therefore, when the transistor is formed using polycrystalline silicon, the switching speed is faster and the response of the display is faster than when the transistor is formed using amorphous silicon. In addition, it is possible to configure the peripheral LSI with thin film transistors. Furthermore, there is an advantage that the design margin of other parts can be reduced. Further, when peripheral circuits such as a driver circuit and a DAC are incorporated in the display, the peripheral circuits can be operated at higher speed.

  Since polycrystalline silicon consists of a collection of crystal grains, for example, when a TFT transistor is formed, a crystal grain boundary is formed in the channel region, and this crystal grain boundary serves as a barrier and mobility of electrons or holes compared to single crystal silicon. Lower. In addition, in many thin film transistors formed using polycrystalline silicon, the number of crystal grain boundaries formed in the channel portion is different among the thin film transistors, and the variation causes a problem of display unevenness if the liquid crystal display device is used. . Therefore, recently, in order to improve the mobility of electrons or holes and to reduce the variation in the number of crystal grain boundaries in the channel portion, a large-grained crystallized silicon having a size capable of forming at least one channel region has been developed. Producing crystallization devices and methods have been proposed.

  Conventionally, as a crystallization method of this kind, a phase shifter (light modulation element) is irradiated with excimer laser light, and a Fresnel diffraction image or an image formation by an image formation optical system is thereby performed as a non-single crystal semiconductor film (polycrystalline semiconductor film or A “phase control ELA (Excimer Laser Annealing) method” in which a non-single crystal semiconductor film) is irradiated to generate a crystallized semiconductor film is known. Details of the phase control ELA method are disclosed in, for example, Surface Science Vol. 21, No. 5, pp. 278-287, 2000.

  In the phase control ELA method, light having a reverse peak pattern (a pattern in which the light intensity is the lowest at the center and the light intensity rapidly increases toward the periphery) is lower than that of the periphery at the point corresponding to the phase shift portion of the phase shifter. An intensity distribution is generated, and the non-single crystal semiconductor film is irradiated with light having the light intensity distribution having the reverse peak shape. As a result, a temperature gradient occurs in the melted region in accordance with the light intensity distribution in the irradiated region, and crystal nuclei are formed in the part that first solidifies or does not melt corresponding to the point where the light intensity is the lowest. Crystals grow laterally from the nucleus toward the periphery (hereinafter referred to as “lateral growth” or “lateral growth”), thereby generating single crystal grains having a large grain size.

  In the crystallization apparatus and method, the light modulation element (phase shifter) is illuminated with a laser beam with uniform illuminance through a homogenizer. At this time, the laser beam superimposed on the light modulation element interferes with the action of the homogenizer, and interference fringes are generated on the light modulation element and the non-single crystal semiconductor film. When interference fringes are generated on the non-single-crystal semiconductor film, a desired light intensity distribution is not formed on the non-single-crystal semiconductor film, and as a result, a region that is crystallized as desired and a region that is not crystallized as desired are periodic. Will be mixed.

  Conventionally, various apparatuses for reducing the generation of interference fringes on a predetermined surface have been proposed in apparatuses (laser annealing apparatus, laser irradiation apparatus, etc.) that irradiate a predetermined surface with laser light with uniform illuminance through a homogenizer. (See Patent Document 1, Patent Document 2, Patent Document 3, etc.). For example, Patent Document 1 discloses a technique for reducing time coherency by the action of a coherence eliminating element formed by stacking a plurality of parallel flat plates having different lengths in the optical axis direction in a stepped manner. .

JP 2003-167213 A JP 2004-012757 A JP 2005-294493 A

  In the prior art disclosed in Patent Document 1, it is difficult to form stepped edges of a plurality of parallel flat plates stacked stepwise with a required accuracy, and thus it is difficult to manufacture a coherence eliminating element. is there. In addition, since the length along the optical axis of the coherence canceling element is relatively large, a relatively large installation space is required for incorporating the coherence canceling element in the optical path, and the size of the optical system is increased. As a result, the size of the apparatus tends to increase. In addition, since a plurality of parallel flat plates are integrated in a stepped manner, it takes time to position the coherence eliminating element at a required position in the optical path.

  The present invention has been made in view of the above-described problems, and it is possible to satisfactorily suppress the generation of interference fringes on a non-single crystal semiconductor film without incurring an increase in the size of an optical system according to a simple configuration. An object is to provide a crystallization apparatus and a crystallization method.

In order to solve the above-described problem, the first embodiment of the present invention is a crystallization apparatus that generates a crystallized semiconductor film by irradiating a non-single crystal semiconductor film with light having a predetermined light intensity distribution,
An illumination system that illuminates the light modulation element via a homogenizer having a plurality of cylindrical lens elements arranged along a predetermined direction;
An imaging optical system that forms the predetermined light intensity distribution based on light through the light modulation element;
There is provided a crystallization apparatus comprising a plurality of strip-shaped optical members provided at intervals of one for each of the plurality of cylindrical lens elements.

According to a second aspect of the present invention, there is provided a crystallization method for generating a crystallized semiconductor film by irradiating a non-single crystal semiconductor film with light having a predetermined light intensity distribution,
An illumination step of illuminating the light modulation element via a homogenizer having a plurality of cylindrical lens elements arranged along a predetermined direction;
Forming the predetermined light intensity distribution on the non-single crystal semiconductor film based on light through the light modulation element;
An applying step of providing an optical path length difference equal to or greater than a temporal coherence length between two adjacent cylindrical lens elements by using a plurality of strip-like optical members provided every other cylindrical lens element; A crystallization method is provided.

  According to a third aspect of the present invention, there is provided a device manufactured using the crystallization apparatus of the first form or the crystallization method of the second form.

  In the present invention, a plurality of strip-shaped optical members are provided for every other cylindrical lens elements arranged in a predetermined direction in the homogenizer, so that a required optical path length is provided between two adjacent cylindrical lens elements. A difference, for example, an optical path length difference equal to or greater than the temporal coherence length is given. As a result, in the present invention, interference fringes are generated on the non-single-crystal semiconductor film without reducing the size of the optical system in accordance with a simple configuration by the action of reducing the time coherency by the plurality of strip-shaped optical members. It can be suppressed well.

  Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a diagram schematically showing a configuration of a crystallization apparatus according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing the internal configuration of the illumination system of FIG. In FIG. 1 and FIG. 2, illustration of characteristic components of this embodiment is omitted to facilitate understanding of the basic configuration and operation of the crystallization apparatus. Further, in FIG. 2, in order to facilitate understanding of the description, the configuration from the light source 21 to the light modulation element 1 is shown along the optical path developed in a straight line with the optical path bending mirrors M1 and M2 omitted. In addition, a local coordinate system (x, y, z) is set.

  Referring to FIGS. 1 and 2, the crystallization apparatus of the present embodiment includes an optical modulation element (phase shifter) 1 for phase-modulating an incident light beam to form a light beam having a predetermined light intensity distribution, and an optical modulation. An illumination system 2 for illuminating the element 1, an imaging optical system 3, and a substrate stage 5 for holding a substrate 4 to be processed are provided. The illumination system 2 includes a XeCl excimer laser light source 21 that supplies laser light having a wavelength of, for example, 308 nm. As the light source, other suitable light sources having a capability of emitting an energy beam for melting the substrate to be processed 4 such as a KrF excimer laser light source or a YAG laser light source may be used.

  For example, the laser light emitted from the XeCl excimer laser light source 21 has a rectangular cross section extending in the y direction perpendicular to the paper surface of FIG. The laser light from the light source 21 is reflected by a mirror M1 (not shown in FIG. 2) and then enters the shaping optical system 22. The shaping optical system 22 reduces the incident light beam having a rectangular cross section elongated in the y direction along the y direction and expands along the x direction parallel to the paper surface of FIG. The light is shaped into a light beam having a cross section and emitted. The laser light shaped by the shaping optical system 22 enters the homogenizer 23 as substantially parallel light.

  The homogenizer 23 includes a first cylindrical lens array 23a and a second cylindrical lens array 23b that are arranged close to each other along the optical axis. The first cylindrical lens array 23a is configured by arranging a plurality of cylindrical lens elements 23aa having refractive power in the xz plane and having no refractive power in the yz plane along the x direction. The second cylindrical lens array 23b is configured by arranging a plurality of cylindrical lens elements 23ba having refractive power in the yz plane and having no refractive power in the xz plane along the y direction. The arrangement of the first cylindrical lens array and the second cylindrical lens array may be reversed.

  The light incident on the homogenizer 23 is divided into wavefronts at the intersections of the cylindrical lens elements 23aa and 23ba, and a plurality of small light sources are formed on the rear focal plane or in the vicinity thereof. Light beams from the plurality of small light sources are reflected by a mirror M2 (not shown in FIG. 2), and then illuminate the light modulation element 1 in a superimposed manner via a condenser optical system 24. The laser light phase-modulated by the light modulation element 1 is reflected by the mirror M3 and then enters the substrate 4 to be processed via the imaging optical system 3 supported by the gantry 6, for example.

  The imaging optical system 3 optically conjugates the phase pattern surface of the light modulation element 1 and the substrate 4 to be processed. In other words, the substrate 4 to be processed (strictly, the irradiated surface of the substrate 4 to be processed) is set to a surface optically conjugate with the phase pattern surface of the light modulation element 1 (image surface of the imaging optical system 3). Has been. The imaging optical system 3 includes, for example, two positive lens groups and an aperture stop disposed between these lens groups. The size of the aperture (light transmitting portion) of the aperture stop (and hence the image-side numerical aperture NA of the imaging optical system 3) is the required light intensity on the non-single crystal semiconductor thin film (irradiated surface) of the substrate 4 to be processed. It is set to generate a distribution. The imaging optical system 3 may be a refractive optical system, a reflective optical system, or a refractive / reflective optical system.

The substrate 4 to be processed is formed by sequentially forming a lower insulating film, a non-single crystal semiconductor thin film, and an upper insulating film on the substrate. More specifically, in the present embodiment, the substrate 4 to be processed is a base insulating film, a non-single crystal semiconductor film (for example, amorphous silicon), for example, on a plate glass for a liquid crystal display by chemical vapor deposition (CVD). Film) and a cap film are sequentially formed. The base insulating film and the cap film are insulating films, for example, SiO ₂ films. The base insulating film directly contacts the amorphous silicon film and the glass substrate to prevent foreign matters such as Na in the glass substrate from entering the amorphous silicon film, and the heat of the amorphous silicon film is reduced. Prevents direct transmission to the glass substrate.

  An amorphous silicon film is a semiconductor film to be crystallized. The cap film is heated by a part of the light beam incident on the amorphous silicon film, and stores the heated temperature. This heat storage effect is that when the incidence of the light beam is interrupted, the high temperature portion of the irradiated surface of the amorphous silicon film cools relatively rapidly, but this temperature gradient is relaxed and the large grain size is reduced in the lateral direction. Promotes crystal growth. The substrate 4 to be processed is positioned and held at a predetermined position on the substrate stage 5 by a vacuum chuck or an electrostatic chuck.

  In the crystallization apparatus of the present embodiment, the light intensity distribution having an inverse peak shape in which the light intensity is the lowest at the center, for example, and the light intensity rapidly increases toward the periphery, is obtained via the light modulation element 1 and the imaging optical system 3. The non-single crystal semiconductor film of the substrate 4 to be processed is irradiated with the light that it has. As a result, in the irradiated region on the non-single-crystal semiconductor film, a temperature gradient is generated in the molten region according to the light intensity distribution, and the crystal is crystallized in the part that solidifies first or does not melt corresponding to the point where the light intensity is the lowest. Nuclei are formed, and crystals grow laterally from the crystal nuclei toward the periphery, thereby generating single crystal grains having a large grain size.

  In the crystallization apparatus of the present embodiment that irradiates the light modulation element 1 with the laser light with uniform illuminance via the homogenizer 23, unless special measures are taken, the light modulation element 1 and the substrate 4 to be processed are not treated. Interference fringes are likely to occur on the single crystal semiconductor film. Hereinafter, this point will be described. In the crystallization apparatus of the present embodiment, as shown in FIG. 3, for example, 7 × 7 = 49 small light sources 31 are arranged on the xy plane via a homogenizer 23 (only the second cylindrical lens array 23b is shown in FIG. 3). Are formed in a matrix.

  Here, both the interval in the x direction and the interval in the y direction of the small light source 31 are d = 2 mm. In other words, the homogenizer 23 includes a first cylindrical lens array 23a including seven cylindrical lens elements 23aa arranged along the x direction, and a second cylindrical lens element 23ba including seven cylindrical lens elements 23ba arranged along the y direction. And a cylindrical lens array 23b. The unit wavefront division area defined by the intersection of the cylindrical lens elements 23aa and 23ba has a square shape of 2 mm × 2 mm.

  The light flux from each small light source 31 illuminates the same region on the light modulation element 1 in a superimposed manner via a condenser optical system 24 having a focal length of f = 543.5 mm, for example. At this time, on the light modulation element 1, an interference fringe having a pitch is generated along the y direction obtained by reducing the incident light beam having a rectangular cross section by the shaping optical system 22. Therefore, based on a two-beam interference model in which a light beam passing through two cylindrical lens elements 23ba adjacent in the y direction interferes on the light modulation element 1, an interval between interference fringes formed on the light modulation element 1 ( y-direction pitch) Dm is calculated.

According to the two-beam interference model described above, the distance Dm between the interference fringes formed on the light modulation element 1 is such that the wavelength λ of light is 308 nm = 0.308 × 10 ⁻⁶ mm. ).
Dm = f × λ / d
= 543.5 × 0.308 × 10 ⁻⁶ / 2
≒ 0.0837mm = 83.7μm (1)

The distance Ds between the interference fringes formed on the non-single crystal semiconductor film of the substrate 4 to be processed is expressed by the following equation (2) when the imaging magnification of the imaging optical system 3 is β = 1/5. Is required.
Ds = Dm × β
= 83.7 / 5
≒ 16.7μm (2)

  In the crystallization apparatus of this embodiment, when no special measures are taken, as shown schematically in FIG. 4, interference fringes having a distance (pitch) Ds ′ of about 16.5 μm along the y direction are formed on the substrate to be processed. It was confirmed by experiment that it was formed on the non-single crystal semiconductor film. In FIG. 4, the difference in intensity between the hatched region 41 having a relatively small light intensity and the region 42 having a relatively large light intensity was about ± 5%. In other words, the peak-to-peak intensity difference between region 41 and region 42 was about 10%.

  As described above, the calculation result by the two-beam interference model and the experimental result almost coincide with each other, and two cylindrical lenses adjacent to each other along the y direction in which the incident light beam having a rectangular cross section is reduced by the shaping optical system 22. It has been found that the light beam that has passed through the element 23ba interferes on the light modulation element 1 and the non-single crystal semiconductor film of the substrate 4 to be processed. Therefore, in the present embodiment, as shown in FIG. 5, every other four strip-shaped elements with respect to the seven cylindrical lens elements 23ba in the homogenizer 23 (only the second cylindrical lens array 23b is shown in FIG. 3). By providing the plane-parallel plate 25, a configuration is adopted in which an optical path length difference Ld greater than or equal to the time coherence length Lc is provided between two cylindrical lens elements 23ba adjacent in the y direction.

That is, of the seven cylindrical lens elements 23ba, immediately after the odd-numbered (first, third, fifth, seventh) cylindrical lens elements 23ba from the upper side in FIG. That is, strip-like parallel flat plates 25 having a thickness t are attached one by one. Here, the time coherence length Lc is obtained by the following equation (3) when the half-value width Δλ of the laser light emitted from the XeCl excimer laser light source 21 is 0.1 nm.
Lc = λ ² / Δλ
= (0.308 × 10 ⁻⁶ ) × (0.308 × 10 ⁻⁶ ) /0.1×10 ⁻⁹
≒ 1mm (3)

Therefore, the minimum thickness t1 of the strip-shaped parallel flat plate 25 required to give the optical path length difference Ld of the time coherence length Lc or more between two cylindrical lens elements 23ba adjacent along the y direction is parallel. When the refractive index with respect to the wavelength λ of the optical material forming the flat plate 25 is n = 1.5, the following equation (4) is obtained.
t1 = Lc / (n-1)
≒ 1 / (1.5-1)
≒ 2mm (4)

  In this embodiment, immediately after the plurality of cylindrical lens elements 23ba in the homogenizer 23, every other parallel plane plate 25 having a strip shape with a thickness t = 1 mm formed of synthetic quartz having a refractive index n = 1.5. The interference fringes formed on the non-single crystal semiconductor film of the substrate 4 to be processed are actually provided in a state where the optical path length difference Ld of the time coherence length Lc or more is given between two adjacent cylindrical lens elements 23ba. Observed. As a result, it was confirmed that interference fringes are hardly formed on the non-single crystal semiconductor film of the substrate 4 to be processed.

  As described above, in the present embodiment, among the two cylindrical lens arrays 23a and 23b constituting the homogenizer 23, the incident light beam having a rectangular cross section is arranged by the shaping optical system 22 along the y direction. By providing every other cylindrical parallel flat plate (generally an optical member) 25 for each of the plurality of cylindrical lens elements 23ba, an optical path length equal to or greater than the time coherence length Lc between two adjacent cylindrical lens elements 23ba. A difference Ld is given. In addition, it is preferable to apply AR coating (non-reflective coating) to the incident surface and exit surface of the strip-shaped parallel flat plate 25.

  In the present embodiment, high accuracy is obtained with respect to the external shape (thickness t, corner edge, etc.) of a plurality of (four in the example of FIG. 5) strip-like parallel flat plates 25 as means for reducing temporal coherency. Is not required. Further, since the plurality of parallel flat plates 25 are arranged in parallel along a plane (xy plane) orthogonal to the optical axis, the installation space required for incorporating these strip-like parallel flat plates 25 into the optical path is small. The optical system is not increased in size. Furthermore, high accuracy is not required for positioning of the plane parallel plate 25 in the optical axis direction (z direction) and the optical axis orthogonal direction (x direction, y direction) with respect to the group of cylindrical lens elements 23ba.

  Therefore, unlike the prior art in which it is difficult to form the edges of the steps of a plurality of parallel plane plates stacked in a staircase shape with the required accuracy, the outer shape (including the thickness t) of the parallel plane plate 25 is particularly important. In the present embodiment where high accuracy is not required, it is easy to individually manufacture the strip-like parallel flat plate 25. Further, unlike the prior art in which a relatively large installation space is required to incorporate a coherence eliminating element having a relatively large length along the optical axis into the optical path, it has a relatively thin strip shape with a thickness t. In the present embodiment in which the plane parallel plates 25 are arranged in parallel, the optical system can be downsized, and thus the apparatus can be downsized.

  Furthermore, unlike the prior art, which takes time to position the coherence eliminating element, which is an integrated stack of a plurality of parallel plane plates in a staircase shape, at a required position in the optical path, the strip-like parallel plane plate 25 is provided. In the present embodiment in which positioning is individually performed with respect to the corresponding cylindrical lens element 23ba, positioning adjustment of each plane-parallel plate 25 can be performed quickly. As a result, in the present embodiment, the non-single crystal semiconductor film of the substrate 4 to be processed is caused by the action of reducing the time coherency by the plurality of strip-like parallel flat plates 25 without causing an increase in the size of the optical system according to a simple configuration. The occurrence of interference fringes can be satisfactorily suppressed.

  In the above-described embodiment, an optical path length difference Ld equal to or greater than the time coherence length Lc is provided between two adjacent cylindrical lens elements 23ba using a plane parallel plate 25 having a thickness equal to or greater than t1. However, the present invention is not limited to this. For example, a configuration in which an optical path length difference smaller than the temporal coherence length Lc is provided between two adjacent cylindrical lens elements 23ba using a plane parallel plate thinner than the above-described t1. Even if it is adopted, the occurrence of interference fringes on the non-single crystal semiconductor film of the substrate 4 to be processed can be suppressed to some extent due to the effect of reducing the time coherency of the plurality of parallel flat plates.

  Further, in the above-described embodiment, the strip-shaped parallel flat plates 25 are attached one by one immediately after the odd-numbered cylindrical lens elements 23ba in FIG. However, the present invention is not limited to this, and as shown in the modification of FIG. 6, a strip-like parallel shape is provided immediately after the even-numbered (second, fourth, sixth) cylindrical lens element 23 ba from the upper side in FIG. 6. One flat plate 25 may be provided one by one. Further, one strip-like parallel flat plate 25 may be provided one by one immediately before the odd-numbered or even-numbered cylindrical lens element 23ba in FIG. Furthermore, strip-like parallel flat plates 25 may be provided one by one immediately before and after the odd-numbered or even-numbered cylindrical lens element 23ba in FIG.

FIG. 7 is a process cross-sectional view illustrating a process of manufacturing an electronic device in a region crystallized using the crystallization apparatus of this embodiment. As shown in FIG. 7A, on a transparent insulating substrate 80 (for example, alkali glass, quartz glass, plastic, polyimide, etc.), a base film 81 (for example, SiN with a film thickness of 50 nm and SiO with a film thickness of 100 nm). ₂ laminated film) and an amorphous semiconductor film 82 (for example, a semiconductor film of Si, Ge, SiGe, etc. with a film thickness of about 50 nm to 200 nm) and a cap film 82a (not shown) with a film thickness of 30 nm to 300 nm A substrate 5 to be processed is prepared by depositing _two films using a chemical vapor deposition method or a sputtering method. Then, a laser beam 83 (for example, a KrF excimer laser beam or a XeCl excimer laser beam) is irradiated onto a predetermined region on the surface of the amorphous semiconductor film 82 using the crystallization apparatus according to the present embodiment. .

Thus, as shown in FIG. 7B, a polycrystalline semiconductor film or a single crystallized semiconductor film 84 having crystals with a large grain size is generated. Next, after removing the cap film 82a from the semiconductor film 84 by etching, as shown in FIG. 7C, a polycrystalline semiconductor film or a single crystallized semiconductor film 84 is formed using a photolithography technique, for example, a thin film transistor. Then, an island-shaped semiconductor film 85 to be a region for processing is processed, and a SiO ₂ film having a film thickness of 20 nm to 100 nm is formed as a gate insulating film 86 on the surface by chemical vapor deposition or sputtering.

  Further, as shown in FIG. 7D, a gate electrode 87 (for example, silicide or MoW) is formed on the gate insulating film, and impurity ions 88 (in the case of an N-channel transistor) using the gate electrode 87 as a mask. Phosphorus and boron in the case of a P-channel transistor are ion-implanted. Thereafter, annealing is performed in a nitrogen atmosphere (for example, at 450 ° C. for 1 hour) to activate the impurities and form the source region 91 and the drain region 92 in the island-shaped semiconductor film 85. Next, as shown in FIG. 7E, an interlayer insulating film 89 is formed to make contact holes, and a source electrode 93 and a drain electrode 94 connected to a source 91 and a drain 92 connected by a channel 90 are formed.

  In the above steps, the polycrystalline semiconductor film or single crystallized semiconductor film 84 generated in the steps shown in FIGS. 7A and 7B is aligned with the position of the large grain crystal, that is, the channel is formed in the crystal grain. 90 is formed. Through the above steps, a thin film transistor (TFT) can be formed in a polycrystalline transistor or a single crystal semiconductor. Polycrystalline transistors or single crystal transistors thus manufactured can be applied to driving circuits such as liquid crystal display devices (displays) and EL (electroluminescence) displays, and integrated circuits such as memories (SRAM and DRAM) and CPUs. is there.

It is a figure which shows roughly the structure of the crystallization apparatus concerning embodiment of this invention. It is a figure which shows schematically the internal structure of the illumination system of FIG. It is a figure explaining the view which calculates the space | interval of the interference fringe formed on a light modulation element and the non-single-crystal semiconductor film of a to-be-processed substrate with a two-beam interference model. It is a figure which shows typically the interference fringe confirmed that it was formed on the non-single-crystal semiconductor film of a to-be-processed substrate by experiment. It is a figure which shows roughly the characteristic principal part structure of this embodiment. It is a figure which shows roughly the characteristic principal part structure in the modification of this embodiment. It is process sectional drawing which shows the process of producing an electronic device using the crystallization apparatus of this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light modulation element 2 Illumination system 3 Imaging optical system 4 Substrate 5 Substrate stage 6 Base 21 Light source 22 Shaping optical system 23 Homogenizer 23a, 23b Cylindrical lens array 23aa, 23ba Cylindrical lens element 24 Condenser optical system 25 Strip-shaped parallel Planar plate 41 Region with relatively low light intensity 42 Region with relatively high light intensity 80 Insulating substrate 81 Underlayer film 82 Semiconductor film 83 Laser beam 84 Semiconductor film 85 Semiconductor film 86 Gate insulating film 87 Gate electrode 88 Impurity ions 89 Interlayer insulating film 90 channel 91 source 92 drain 93 source electrode 94 drain electrode

Claims (9)

A crystallization apparatus for generating a crystallized semiconductor film by irradiating a non-single crystal semiconductor film with light having a predetermined light intensity distribution,
An illumination system that illuminates the light modulation element via a homogenizer having a plurality of cylindrical lens elements arranged along a predetermined direction;
An imaging optical system that forms the predetermined light intensity distribution based on light through the light modulation element;
A crystallization apparatus comprising a plurality of strip-like optical members provided at intervals of one for each of the plurality of cylindrical lens elements. 2. The crystallization apparatus according to claim 1, wherein the strip-shaped optical member imparts an optical path length difference equal to or greater than a temporal coherence length between two adjacent cylindrical lens elements. 3. The crystallization apparatus according to claim 1, wherein the strip-shaped optical member includes a plane-parallel plate disposed immediately before or after the cylindrical lens element. The crystallization apparatus according to any one of claims 1 to 3, wherein the plurality of strip-shaped optical members have the same length along the optical axis. 5. The illumination system includes a light source that supplies a light beam having a rectangular cross section, and a shaping optical system that reduces the light beam emitted from the light source along the predetermined direction. The crystallization apparatus according to 1. A crystallization method for generating a crystallized semiconductor film by irradiating a non-single crystal semiconductor film with light having a predetermined light intensity distribution,
An illumination step of illuminating the light modulation element via a homogenizer having a plurality of cylindrical lens elements arranged along a predetermined direction;
Forming the predetermined light intensity distribution on the non-single crystal semiconductor film based on light through the light modulation element;
An applying step of providing an optical path length difference equal to or greater than a temporal coherence length between two adjacent cylindrical lens elements by using a plurality of strip-like optical members provided every other cylindrical lens element; Including crystallization method. The crystallization method according to claim 6, wherein in the applying step, a parallel plane plate disposed immediately before or after the cylindrical lens element is used as the strip-shaped optical member. The crystallization method according to claim 6 or 7, wherein in the illuminating step, a light beam having a rectangular cross section emitted from a light source is reduced along the predetermined direction. A device manufactured using the crystallization apparatus according to any one of claims 1 to 5 or the crystallization method according to any one of claims 6 to 8.

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