JPH08129189A - Production of liquid crystal display substrate, apparatus therefor, method for evaluating semiconductor crystal, production of semiconductor crystal thin film and production device of semiconductor crystal thin film - Google Patents

Abstract

PURPOSE: To make it possible to assure the good performance of driving circuit parts in a process for producing an LCD substrate by forming the driving circuit parts on amorphous semiconductor films formed on a glass substrate. CONSTITUTION: The amorphous silicon film 2 is formed by a reduced pressure CVD on the glass substrate 1. This amorphous silicon film 2 is irradiated with laser beams in an island form to polycrystallize the irradiated regions. In such a case, for example, each region is irradiated with the energy below the irradiation energy necessary for the polycrystallization and is then irradiated with the necessary energy. The band gap spectral reflectivity of the reflected light of the irradiated regions and the spectral reflectivity of a reference are compared and the energy is controlled while the progressing condition of the crystallization state is recognized by the degree of approximation thereof. The interior of the irradiated regions is thereafter subjected repeatedly to a film forming treatment and etching, by which the driving circuit parts consisting of the semiconductor elements are formed. For example, the wiring with a previously formed TFTs 5 is executed by the film forming treatment in this stage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a liquid crystal display substrate, an apparatus therefor, a method for evaluating a semiconductor crystal, a method for producing a semiconductor crystal thin film, and an apparatus for producing a semiconductor crystal thin film.

[0002]

2. Description of the Related Art L using a TFT (thin film transistor)
CDs (Liquid Crystal Displays) have been attracting attention as they provide extremely high image quality. LCD of this kind
The substrate is a TFT on the glass substrate 1a as shown in FIG.
1b is formed and, for example, a pixel electrode 1c electrically connected to the drain electrode thereof is arranged with a gap between the pixel electrode 1c and the TFT 1b, and a large number of pixel units U combined in this way are arranged. For example, one side is several hundred μ
Hundreds of thousands of rectangular pixel units U of about m are arranged.

A transparent electrode 1d common to each pixel unit U is arranged so as to face each other on a glass substrate on which the pixel unit U is formed with a gap therebetween, and a liquid crystal 1e is sealed in the gap to form the pattern shown in FIG. As shown in FIG.
Is formed. Further, on the glass substrate 1a outside the pixel section 10, a plurality of IC chips 11 forming a packaged drive circuit section are arranged along the periphery of the pixel section 10, and the terminals of each IC chip 11 are arranged in the pixel section. The LCD substrate is configured by being connected to the gate wirings and the drain wirings which are the scanning electrode wirings corresponding to the respective 10 pixel units U.

Regarding the conventional method of manufacturing such an LCD substrate, first, for example, plasma CV is formed on the glass substrate 1a.
After forming a hydrogenated amorphous silicon film by D, a process such as film formation and etching is performed on this film to form a large number of TFTs and pixel electrodes and scan electrodes electrically connected to the TFTs. , To form a large number of pixel units U
After the above, the packaged IC chip 11 is attached to the glass substrate 1a, and the IC chip 11 and the scanning electrode wiring formed in the pixel unit are aligned and connected, and then the liquid crystal 1e is sealed. I am trying to do it.

[0005]

The TFT-LCD as described above is strongly desired to have a large area and high color display quality, and wiring from the gate drive circuit section (gate driver) and source drive circuit section ( There are some wirings from the source driver) to, for example, 400 lines and 1920 lines, respectively. For this reason, alignment of both of them for electrically connecting the drive circuit section 11 and each scanning electrode of the TFT liquid crystal pixel section is performed. The work requires a lot of man-hours, which is one of the factors for increasing the price of LCDs.

Therefore, if it is technically possible to perform film formation processing on the same glass substrate to form the switching elements of the drive circuit section and simultaneously perform the wiring between the drive circuit section and the pixel section, the drive circuit will be solved. Since the drive circuit portion and the scanning electrode wiring can be connected at the same time in the step of forming the portion, the step of attaching the IC chip on the glass substrate and the wiring work between the both are unnecessary, which is very effective. That's the method.

Here, regarding the TFT of the pixel unit,
Due to the function of displaying the pixels as an image, high speed is not required so much, so amorphous silicon can be used as the semiconductor layer, but the drive circuit part is equipped with a circuit that requires high-speed switching operation. Since the operating speed must be considerably faster than that of the TFT, that is, it must have a performance equivalent to that of an IC chip, the semiconductor layer has a field effect mobility higher than that of amorphous silicon. (Mobile
It is necessary to use polycrystalline silicon having a large ty).

On the other hand, in order to obtain polycrystalline silicon (polysilicon), it is necessary to heat the film to a temperature of about 600 ° C. or more by low pressure CVD to perform the film forming process, but a low cost glass substrate has a thermal strain point of 600 ° C. About 600 ℃
Since the glass substrate that can withstand a high temperature is expensive, the LCD price will eventually increase.

From the above, first, for example, plasma C
A large area hydrogenated amorphous silicon film (hereinafter referred to as "a-Si: H") is formed on a glass substrate in an atmosphere at a temperature of about 300 ° C. by VD.
Film)) and then irradiating the a-Si: H film with a laser beam to locally apply, for example, a surface temperature of 12
It is heated to about 00 ° C., whereby a-Si:
A method of forming a polycrystal silicon film by polycrystallizing the H film and using this as a semiconductor layer to form a drive circuit portion has been studied.

According to this method, since the heating temperature at the time of forming the a-Si: H film is low, a good quality film can be obtained at a low temperature on a large glass substrate, and the heat treatment by laser light, that is, laser annealing is performed. Since the amorphous silicon film is instantaneously heated (for example, 23 nsec in the case of KrF) to be polycrystallized, heat is not transmitted to the glass substrate, and therefore, a large heat resistance is not required for the glass substrate, so an inexpensive material is used. Therefore, a large-area transmissive liquid crystal display can be manufactured.

By the way, a method of polycrystallizing an a-Si: H film by laser light is a-Si: H at the time of laser light irradiation.
Since hydrogen is released from the film, it is necessary to avoid damage to the film due to hydrogen release. For this reason, various studies have been conducted on the amount of laser beam irradiation energy and the irradiation method. Here, the present inventor, when irradiating the laser light along the periphery of the pixel region, irradiates the surface of the a-Si: H film with the laser light in a pulsed manner to form the polycrystallized drive circuit portion region. A method of forming a strip shape along the periphery of the pixel area and arranging the drive circuit portions in the drive circuit portion area is being studied.

However, this method has the following problems. That is, FIG. 20 is a diagram showing the relationship between the movement of the laser light pulse and the field-effect mobility in the irradiation region, and the intensity distribution of the laser light is uniform in the irradiation surface direction. It is trapezoidal in the direction orthogonal to it. As shown in FIG. 20A, when there is no overlapping portion of the laser light pulses (pulse irradiation areas), the irradiation energy of the laser light is not substantially supplied at the pulse boundary portion, so a-Si: It remains H. Here, the field effect mobility (mo) of polycrystalline silicon and a-Si: H.
bilities) are, for example, 30 to 600 cm ² / V.
s, 0.3 to ¹ cm ² / V · s, and the field-effect mobility of polycrystalline silicon is two or more orders of magnitude higher than that of a-Si: H. Therefore, such an a-Si: H region is polycrystalline. When it is present in the silicon region, the semiconductor elements that form the drive circuit section have large variations.

In addition, as shown in FIG. 20 (b), when there is a portion where the pulses of the laser light overlap, the field effect mobility varies for the following reasons. That is, after the a-Si: H film is polycrystallized in the first irradiation region as shown in FIG.
When the irradiation region is polycrystallized, a region where the laser light is irradiated twice occurs in both regions. Therefore, even if the lateral mode of the laser light (laser power cross section) is uniform, many regions are irradiated. The melting points of crystalline silicon and a-Si: H are 1414 ° C. and 1000, respectively.
Since the melting point is 0 ° C. and the melting points are different, it is difficult to make the field effect mobility uniform at the joint of the irradiation region of the laser light, as can be seen from the field effect mobility diagram of FIG. Is.

The present invention has been made under such circumstances, and an object of the present invention is to provide a method for manufacturing an LCD substrate which does not deteriorate the performance of a drive circuit section, and a method for implementing the method. To provide a suitable device.

Another object of the present invention is to provide a method for evaluating a semiconductor crystal, which enables simple and low-cost real-time evaluation of a crystallized state of a semiconductor.

Still another object of the present invention is to provide a method for manufacturing a semiconductor thin film and a manufacturing apparatus therefor capable of easily and inexpensively evaluating the crystallized state of a semiconductor in real time and improving the yield of products. It is in.

[0017]

According to another aspect of the present invention, there is provided a liquid crystal display comprising a plurality of switching elements arranged in a pixel region on a substrate and a plurality of drive circuit sections for driving the switching elements. In the method of manufacturing a substrate, a step of forming an amorphous semiconductor film on the substrate,
A step of intermittently irradiating the amorphous semiconductor film with a pulse of laser light to polycrystallize the irradiated region to form a polycrystalline island-shaped region in the amorphous semiconductor film; In the region, a step of forming a drive circuit portion in which a polycrystalline region of this region is used as a semiconductor region, and a part of an amorphous semiconductor film being used as a semiconductor region, and a switching element electrically connected to the drive circuit portion is formed into a pixel. And a step of forming in the region.

According to a second aspect of the present invention, there is provided a method of manufacturing a liquid crystal display substrate comprising a switching element arranged in a pixel region on a substrate and a shift register for driving the switching element. A step of forming an amorphous semiconductor film, a step of irradiating the amorphous semiconductor film with a pulse of laser light in a plurality of islands to polycrystallize the amorphous semiconductor film, A step of dividing and generating the shift register in a pulse irradiation region, and a step of forming a wiring layer for electrically connecting the divided shift registers and the shift register and the switching element. It is characterized in that at least a transistor of the shift register is arranged in an irradiation region of a pulse of laser light.

A third aspect of the present invention is a method for evaluating the crystallization state of a semiconductor, which comprises irradiating a reference semiconductor crystal material in an optimum crystallization state with laser light and spectrally detecting the reflected light. The bandgap spectral reflectance distribution of the reference semiconductor crystal material obtained from the detected value.
Of storing information in advance, and irradiating a laser beam to the evaluation region of the semiconductor to be evaluated, and spectroscopically detecting the reflected light, and the second value related to the bandgap spectral reflectance distribution of the evaluation region from the detected value. It is characterized by including a step of acquiring information and a step of comparing the first information and the second information and evaluating the crystallization state of the semiconductor by the degree of approximation thereof.

A fourth aspect of the present invention is a method for producing a semiconductor crystal thin film while crystallizing an amorphous region of an object to be processed by a laser annealing treatment and evaluating the crystallized state thereof. The reference semiconductor crystal thin film in the state is irradiated with laser light, the reflected light is spectrally detected, and first information about the bandgap spectral reflectance distribution of the reference semiconductor crystal thin film acquired from the detected value is stored in advance. A second step relating to the bandgap spectral reflectance distribution of the laser irradiation region of the object to be processed from the detected value by spectrally detecting the reflected light from the evaluation region of the object to be processed while performing the laser annealing process. The step of obtaining the information of step 1 is compared with the first information and the second information, and the laser irradiation energy is adjusted so that the degree of approximation falls within a predetermined range. Characterized by comprising the that step.

According to a fifth aspect of the present invention, the processing chamber, means for supporting the object to be processed having the semiconductor crystal thin film in the processing chamber, and annealing the thin film by irradiating the semiconductor crystal thin film with laser light. Laser irradiation means, storage means for pre-storing first information on the bandgap spectral reflectance distribution regarding the reference semiconductor crystal thin film in the optimum crystallization state, and the processed surface of the object to be processed from the laser irradiation means. Laser spectroscopic detection means for spectroscopically detecting reflected light that has been irradiated onto the processing surface and reflected from the processing surface to obtain second information regarding the bandgap spectral reflectance distribution of the laser irradiation region of the processing surface; Comparison and evaluation means for comparing and evaluating the second information acquired by the laser spectroscopic detection means with the first information stored in the storage means; Based on the evaluation signal output from the comparison evaluation means, the laser irradiation energy of the laser irradiation means is adjusted so that the degree of approximation between the first information and the second information falls within a predetermined range. And a laser irradiation energy adjusting means.

According to a sixth aspect of the present invention, a step of forming an amorphous semiconductor film on a substrate, and a pulse of laser light is intermittently irradiated to the amorphous semiconductor film, and the irradiation area is increased. A step of crystallizing to form a polycrystalline island region in the amorphous semiconductor film; a step of forming a drive circuit section in which the polycrystalline island region is a semiconductor region in the polycrystalline island region; Forming a switching element electrically connected to the drive circuit section in a pixel region with a part of the crystalline semiconductor film as a semiconductor region, and irradiating a reference semiconductor crystal material in an optimal crystallized state with laser light Then, the reflected light is spectrally detected, and the first information regarding the bandgap spectral reflectance distribution of the reference semiconductor crystal material obtained from the detected value is stored in advance, and the polycrystalline island region is formed. In the process, from the amorphous semiconductor film The reflected light of the laser light is spectrally detected, and the step of acquiring the second information regarding the bandgap spectral reflectance distribution of the evaluation region from the detected value is compared with the first information and the second information. And a step of evaluating the crystallized state of the semiconductor according to the degree of approximation.

According to a seventh aspect of the present invention, there is provided a substrate loading section on which a cassette containing a plurality of unprocessed substrates is placed.
Alignment means for aligning the substrate to be processed,
A plurality of processing devices arranged on both sides of a common transfer path, a first transfer means for transferring a substrate to be processed in a cassette placed in the substrate loading section to an alignment means, and the common transfer path And a second transfer unit that moves the substrate to be processed between the position adjustment unit and each of the processing devices, and the substrate transfer unit, the position adjustment unit, the first transfer unit, and the second transfer unit. The transport path of the second transport means is characterized by being provided in the atmosphere or in a non-oxidizing gas atmosphere having a pressure of atmospheric pressure or higher.

According to an eighth aspect of the present invention, in the liquid crystal display substrate manufacturing apparatus according to the seventh aspect, the plurality of processing devices include a preheating device for preheating the substrate to be processed, and an amorphous semiconductor on the substrate to be processed. The apparatus includes a film forming processing apparatus for forming a film, a cooling apparatus for cooling the substrate to be processed, and a laser annealing apparatus for annealing the amorphous semiconductor film on the processing substrate with laser light to polycrystallize the film. It is characterized by

According to a ninth aspect of the invention, in the apparatus for manufacturing a liquid crystal display substrate according to the seventh or eighth aspect, the substrate unloading unit, in which a cassette for storing a plurality of processed substrates is placed, comprises: It is characterized in that it is provided in the transport area of one transport means, and the first transport means transfers the substrate to be processed from the alignment means into the cassette placed on the substrate unloading section.

According to a tenth aspect of the invention, in the liquid crystal display substrate manufacturing apparatus according to the seventh, eighth or ninth aspect, the second transfer means is a movable stage movable along a transfer path extending in the X-axis direction. , Provided on this moving stage,
The present invention is characterized by including a transport arm capable of rotating in the θ direction, advancing and retracting in the Y axis direction, and moving in the Z axis direction.

[0027]

According to the first and second aspects of the invention, the amorphous semiconductor film is irradiated with a pulse of laser light in an island shape to be polycrystallized, and at least the semiconductor element of the drive circuit portion is formed in the irradiation region. Therefore, the entire irradiation region is uniformly and favorably polycrystallized, and therefore, good performance can be obtained without variation in any driving circuit unit.

According to the third aspect of the present invention, the crystallization state of the amorphous semiconductor can be evaluated in real time by a simple and low-cost method without using a special and expensive optical system. . According to the method for manufacturing a semiconductor crystal thin film (the invention of claim 4) and the apparatus (the inventions of claims 5 and 6) using the above evaluation method, the crystallization treatment of the amorphous semiconductor is performed by the laser annealing method. However, the crystallization state of the amorphous semiconductor can be evaluated in real time by a low-cost method, and the crystallization process can be feedback-controlled in real time based on the evaluation result, improving product yield and throughput. Can be improved.

According to the invention of claims 7 to 10, it is possible to easily cope with an increase in the number of processes and the number of substrates to be processed, and it is possible to manufacture a liquid crystal display substrate with a high throughput. Since it can be used, the substrate to be processed can be reliably transported at high speed.

[0030]

EXAMPLES Examples of the present invention will be described below. In the examples of the present invention, first, as shown in FIG. 1A, an amorphous semiconductor film is formed on a transparent substrate such as a glass substrate 1 by low pressure CVD. A certain amorphous silicon film 2 is formed. When this step is performed by the low pressure CVD method, for example, monosilane (SiH ₄ ) gas or disilane gas (Si ₂ H ₆ ) is used as a reaction gas, and the substrate temperature is 450 ° C. to 520 ° C., for example.
An amorphous semiconductor film is formed under the reaction condition of pressure Torr.

Next, as shown in FIG. 1B, a laser beam having a square beam cross-sectional shape, for example, one side of which is several millimeters, is applied by the laser beam irradiation unit 3 to one side of the amorphous silicon film 2 in the vertical direction. Irradiate intermittently along one side. As a result, the island-shaped, for example, rectangular irradiation region 21
The mutual distance d is formed to be, for example, about several millimeters. In this irradiation region, amorphous silicon is polycrystallized (polycrystallized) and converted into polycrystalline silicon (polysilicon) by appropriately selecting irradiation conditions as described later.

Regarding the irradiation of laser light, for example, one pulse of laser light having a power density (irradiation energy per unit area) sufficient to polycrystallize an amorphous silicon film by an excimer laser is applied. However, before that, one pulse or a plurality of pulses having a power density smaller than the power density may be irradiated. As the excimer laser, KrF (pulse width 23 nsec) or XeCl (pulse width 25 nsec) is used.
Etc. can be used.

Thereafter, as shown in FIGS. 1C and 2A, the laser light irradiation region 21 of the amorphous silicon film 2 is etched and / or the laser light irradiation region 21 of the vapor deposition film 2 is etched on the region 21 (polycrystalline silicon region). Inside), the prescribed film formation process,
The etching process is repeated to form the drive circuit unit 4 made of a semiconductor element (switching element) having a known configuration, for example, an LSI. These drive circuit units 4 are TFTs described later.
2 is divided into a gate drive circuit portion 41 arranged vertically in FIG. 2 so as to drive the gate electrode thereof and a source drive circuit portion 42 arranged horizontally so as to drive the source electrode of the TFT.

In this embodiment, a group of gate drive circuit sections 41 arranged vertically in a row constitutes a gate shift register, and a group of source drive circuit sections 42 arranged horizontally in a row. The source shift register is constituted by the above. That is, as shown in FIG. 2B, the gate shift register (same as the source shift register) is composed of a plurality of island-shaped shift register units, and a plurality of island regions (irradiation regions 21) each have a plurality of islands. The switching element formed of a transistor is formed, and the shift register portions in these island regions are electrically connected to each other by a wiring layer 40. These wiring layers 40 can be formed together during the manufacturing process of the transistor or TFT at the time of manufacturing them. For example, a conductive material such as aluminum or copper is formed on a portion of the polycrystalline silicon region 21 between the drive circuit portions 4 and an amorphous silicon portion between the portions through an insulating film such as a silicon oxide film. It can be formed by forming a film and selectively etching the film. Note that reference numeral 5
Reference numeral 1 denotes a wiring layer such as a gate bus line or a source bus line described later, which is connected to the pixel region 50 in this example.

Further, a predetermined film forming process and etching are repeatedly performed in the pixel region 50 of the amorphous silicon film 2 to thereby perform a TFT (Thin Fi) functioning as a switching element.
lmTransistors) 5 are formed by arranging in a matrix form vertically and horizontally by the number corresponding to the number of pixels. This T
In this embodiment, the electrical connection between the FT 5 and the drive circuit unit 4 is, for example, the step of forming the TFT 5, the film forming process, the linography, and the etching are repeated to form the gate electrode and the source electrode and the gate bus line simultaneously. This can be performed by forming a wiring layer 51 (see FIG. 5B) made of, for example, aluminum such as a source bus line or the like (the wiring layer 40 can also be formed in the same step). These wiring layers 40 and 51 may be formed at the same time as the electrodes of the semiconductor element of the drive circuit unit 4 are formed, or at the same time when the electrodes of the drive circuit unit 4 and the TFT 5 are formed and at the same time when the electrodes are formed. Alternatively, it may be formed after the TFT 5 and the drive circuit unit 4 are generated.

Further, the semiconductor element and the T forming the drive circuit unit 4
Various device types such as a planar type and an inverted stagger type can be selected for the FT 5, and thus the amorphous silicon film 2 and the polycrystalline silicon region 21 are used to drive the FT 5.
Also, in order to form the TFT 5, an electrode or the like may be located under the amorphous silicon film 2 depending on the type of device. Further, in the above example, the TFT 5 is generated after the drive circuit unit 4 is generated, but the TFT 5 may be generated first, or the drive circuit unit 4 and a part of the TFT 5 may be generated at the same time. . In this way, the LCD substrate 10 is manufactured, a transparent substrate is bonded to the LCD substrate 10, and then liquid crystal is sealed to form an LCD panel.

In the above-mentioned embodiment, the amorphous silicon film 2 is irradiated with a pulse of laser light in an island shape along the periphery of the substrate, that is, the laser light having a cross section having the same dimension as the dimension of the island is irradiated. A large number of laser light irradiation areas 21
Since (island regions) are formed and each island region is polycrystallized, the irradiation energy of the laser light is uniform in the irradiation region 21 of the laser light, and therefore the irradiation energy of the laser light is set to an appropriate value. By so doing, any of the island regions can be uniformly and well polycrystallized. Therefore, the semiconductor element forming the drive circuit portion 4 formed by repeating the film forming process and the etching on the region, that is, on the polycrystalline silicon film, that is, the semiconductor element using polycrystalline silicon as the semiconductor layer is good. As a result, in manufacturing an LCD substrate, a driving circuit part using an amorphous silicon film is formed, and the driving circuit part and T
Since wiring can be realized by the film formation process of FT, LCD
Manufacturing of the substrate is facilitated.

In the above, the method of forming the amorphous silicon film 2 is not limited to the low pressure CVD, but may be formed by plasma CVD. In this case, for example, monosilane gas and hydrogen gas are used, and the reaction temperature is 180 ° C. 300 ° C,
The film can be formed under the condition of a pressure of 0.8 Torr. Here, when plasma CVD is used, hydrogen is taken into the amorphous silicon film to form an a-Si: H film (hydrogenated amorphous silicon film). In the process, it is desirable to irradiate the laser light in the following manner, for example, in order to suppress damage to the film due to rapid release of hydrogen during laser annealing.

That is, the output energy of the laser light is aS
i: H energy is lower than the energy required for polycrystallizing, and is first made small and irradiated with one pulse or a plurality of pulses, and then the energy is increased successively, for example, with one pulse or a plurality of pulses, respectively. In this way, the irradiation region is polycrystallized by gradually releasing the hydrogen in the a-Si: H film and then irradiating, for example, one pulse with an energy equal to or more than the energy required for the polycrystallization at the end. Subsequently, another region is similarly irradiated with laser light to form a polycrystalline silicon region in an island shape. When multiple pulses of laser light are emitted for each energy, the amount of hydrogen released is monitored, and after that amount does not change much for each pulse, the energy is set to the next large value and the same applies. It is desirable to perform the process of.

According to such a method, since hydrogen corresponding to a small energy is sequentially released to hydrogen corresponding to a large energy, hydrogen in the a-Si: H film is released stepwise, and a Since the hydrogen content in the film is already small when a large amount of energy required to polycrystallize the —Si: H film is applied, the film is not damaged even if the hydrogen is released all at once.

Next, a laser annealing device and a monitoring device used for irradiating the amorphous silicon film 2 with a laser beam to polycrystallize it and a method of using these will be described in detail. This apparatus uses an air support mechanism 6 utilizing air pressure as a base of the apparatus as shown in FIGS. 3 and 4.
The air support mechanism 6 is supported by an air suspension in a state where a support plate 61 made of a rigid material such as metal is floated by air pressure, and the air pressure is controlled so that it is always horizontal. A processing chamber, for example, an airtight cylindrical vacuum chamber 63 made of aluminum is mounted and fixed on the support plate 61 via a hollow support base 62. Substrate 2 with an amorphous silicon film on a glass substrate
0 for holding the processed surface downward,
A mounting table 64 is arranged. Reference numeral 64a is a holding portion that holds the peripheral edge of the glass substrate, and 64b is a support rod.

An exhaust pipe 65 connected to, for example, a vacuum pump (not shown) is connected to the vacuum chamber 63, and the amount of hydrogen generated from the amorphous silicon film on the substrate 20 is measured. A mass spectrometer 66 is installed, and a gate valve G for loading / unloading the substrate 20 between the vacuum chamber and the outside (atmosphere).
(Not shown in FIG. 4) is provided. A window 6 made of, for example, synthetic quartz glass is provided on the bottom wall of the vacuum chamber 63 facing the substrate so that a laser beam described later can be transmitted therethrough.
7 are formed.

On the support plate 61 below the vacuum chamber 63, a laser beam irradiation section 7 in which a reflecting mirror 7a (see FIG. 5) is arranged, and this laser beam irradiation section 7 are provided.
A moving mechanism 70 for moving the horizontal direction, for example, the X direction and the Y direction is arranged. The moving mechanism 70 includes, for example, a rail 71 installed on the support plate 61 in the X direction.
The X moving unit 72 moving along the X moving unit 72 and the Y moving unit 74 moving along the rail 73 installed in the Y direction on the X moving unit 72. The Y moving unit 74 is irradiated with the laser beam. The part 7 is mounted.

As shown in FIG. 5, an excimer laser light oscillation source 92 is disposed on the side of the air support mechanism 6 with its laser light emission port facing the reflecting mirror 7a. An optical system beam homogenizer 93 is provided between the excimer laser 92 and the reflecting mirror 7 so that the laser beam emitted from the laser source 92 is shaped into a beam having a predetermined dimension and is incident on the reflecting mirror. ing. In this preferred embodiment, the laser source is a KrF laser which emits a laser beam having a wavelength of 248 nm with a pulse width of 23 nsec or 2
A XeCl laser emitting with a pulse width of 5 nsec is used, and the beam homogenizer 93 is
It is a known one composed of a diffusing member for diffusing an incident laser beam at a wide angle and a fisheye lens for condensing the diffusing light in a predetermined range. The laser source 92 is driven by a laser power source 91 connected to it. The laser source drive signal of the laser power source 91 is controlled by the CPU 90. The CPU 90 is required to operate this device, such as drive information for driving the moving mechanism 70, control information for the laser power source, reference information regarding a bandgap spectral reflectance distribution for evaluating a semiconductor crystal described later, and the like. A memory 94 storing various information is connected. In the figure, reference numeral 86 is arranged outside the support mechanism 6 and is used for the substrate 2
The spectroscope which receives the reflected light from 0 and detects the spectral characteristic of a silicon film is shown.

Next, a method for polycrystallizing the amorphous silicon film 2 using the above-mentioned apparatus will be described. First, the gate valve G is opened and the substrate 20 is moved by a transfer mechanism (not shown).
Is placed on a mounting table 64 in the vacuum chamber 63 with the surface to be processed facing downward, and then the gate valve G is closed, and then the inside of the vacuum chamber 63 is pressurized via the exhaust pipe 65 by a vacuum pump (not shown). Evacuate to a vacuum atmosphere of 2.5 × 10 ⁻⁷ Torr. Thereafter, under the control of the CPU 90, the laser light irradiation unit 7 is intermittently moved in the horizontal direction (X and Y directions) via the moving mechanism 70, and laser light is emitted from the excimer laser light oscillation source. Oscillate toward the part 7. As a result, the transmitted laser light is reflected vertically upward by the reflecting mirror 7a of the laser light irradiation unit 7 and enters the amorphous silicon film of the substrate 20 through the transparent window 67, and this irradiation region is polycrystalline. Turn into. C at this time
The control signal to the laser power source of the PU 20 is set according to the moving time, stop time, moving distance, moving direction, etc. of the moving mechanism 70 stored in the memory 94, and the amorphous silicon film is irradiated with the laser light. The distance between island-shaped irradiation areas, the total length, the direction, etc. are determined. The irradiation area is, for example,
It is set to a rectangular shape of 0.65 cm × 0.65 cm, which is substantially equal to the cross section of the incident laser light, which is determined by the beam homogenizer 93. Therefore, by setting data in the CPU 90 and exchanging or changing the beam homogenizer 93, irradiation regions of arbitrary dimensions, that is, polycrystalline silicon regions can be formed in arbitrary directions at arbitrary intervals. Also, the CPU 9
Under the control of 0, each irradiation region can be irradiated with laser light with a plurality of times of the same energy or different energies as described later.

For example, when irradiating each irradiation region with laser light once to polycrystallize, the pulse width is, for example, 23 ns.
One pulse of a laser light pulse of ec is applied, and then the moving mechanism 70 is driven to irradiate the area similarly separated from the irradiation area by a predetermined distance. By controlling the moving mechanism 70 in this way, the laser light is irradiated to the peripheral edge of the substrate 20. Irradiation can be carried out in the form of islands vertically and horizontally along the part.

Here, plasma C is used as an amorphous silicon film.
It has already been described that when an a-Si: H film is formed on a glass substrate by VD, it is desirable to increase the irradiation energy stepwise when irradiating the a-Si: H film with laser light. However, the results of experiments conducted to confirm the advantages of the method are shown in FIGS. 6 and 7. In the figure, the vertical axis is the output current of the mass spectrometer (corresponding to the amount of hydrogen released), and the horizontal axis is the irradiation energy density of the laser beam.
-Si: H film is divided into 6 regions, and the irradiation energy of the laser beam (oscillation side) for each region 1 to 6 as shown in Table 1.
Is being increased stepwise to check the amount of hydrogen released.

[0048]

[Table 1] However, in FIGS. 5 and 6, the film thickness of the a-Si: H film is 500, respectively.
Angstrom, 300 Angstrom, 2
0 Hz and 10 Hz are laser pulse frequencies.
Also, the optical path length from the laser oscillation source to the substrate is 230 mm,
The beam size is 0.65 cm × 0.65 cm, the pressure in the vacuum chamber is 1.0 × 10 ⁻⁷ Torr in the case of FIG.
In the case of FIG. 7, it is 2.0 × 10 ⁻⁷ Torr. As can be seen from the results of this experiment, the amount of hydrogen released does not increase sharply by increasing the irradiation energy stepwise, so that damage to the film due to hydrogen release can be suppressed.

As described above, instead of irradiating a single irradiation region with laser beams having different energies a plurality of times, it is also meaningful to irradiate the amorphous silicon with laser beams having the same energy a number of times. By irradiating the same portion of the amorphous silicon with laser light having an energy preferably lower than the melting temperature a number of times, the grain size is increased and the orientation is increased, and the amorphous silicon becomes (111 This is because the) surface approaches the silicon single crystal that becomes the irradiation surface and the mobility becomes faster than that of polycrystalline silicon. In this case, it is desirable to carry out under the following conditions.

1. Thickness of amorphous silicon film: 300 to 1500 angstroms, more preferably 500 to 1000 angstroms: If the thickness of the amorphous silicon film is less than this range, it is unsuitable as a semiconductor film, and if it is more than this range, orientation is difficult. .

1. Heating temperature of substrate (amorphous silicon film) Room temperature to 400 ° C. If the temperature is higher than this, the amorphous silicon is softened.

1. Irradiation number (shot number) 30 to 1000 times If the number of shots is less than this range, the effect is small, and if it is more than this range, the time is too long and defects are likely to occur in the formed film, which is not practical.

The number of shots is 32 in FIGS. 8A to 8C.
And the measurement results when the integrated intensity distributions of 128 and 1024 are measured with a goniometer. The conditions for this measurement are as follows: amorphous silicon is formed by PRCVD, its thickness is 700 A °; film temperature is 400 ° C .; laser light source is that of the above-mentioned embodiment; voltage is 40 KV; tube current is 30 mA. Met. As can be understood from this measurement result, when the number of shots is 32 (FIG. 8A), it is 2
Although the intensity peak value at the 8.632 position is not so high as compared with the intensity at other positions, it can be understood that the intensity peak value at the 28.632 position increases as the number of shots increases. It can be understood that it is well known in this field that the higher the intensity peak value at the 28.632 position, the closer to the silicon single crystal having the (111) plane.

Next, with reference to FIGS. 5 and 9, a method for converting the amorphous silicon into polycrystalline silicon and a method for evaluating the crystallinity of polycrystalline silicon will be described.

When performing the laser light irradiation process, in step S1, the CPU 2 based on a signal from the memory 94 in which the control program according to the present invention is incorporated is used as a reference.
The laser power supply 91 is turned on by a command from 0, the laser is transmitted from the excimer laser source 92 through the homogenizer 93 to the laser reflecting mirror 7a, and the laser is further transmitted to the object to be processed on the lower surface of the substrate 20, that is, the non-processing target. Directed toward the desired region within the crystalline silicon film, and
By appropriately driving the moving mechanism 70, the amorphous silicon film in the desired region is sequentially scanned and irradiated with a laser.

Next, in step S2, the substrate 20 is
The reflected light of the laser which has been irradiated onto the amorphous silicon and has been subjected to laser annealing treatment on a desired amorphous silicon region to form polycrystalline silicon is spectrally detected by the spectroscope 86.

Next, in step S3, the spectral reflectance distribution of the band gap reflected in the semiconductor crystal region of the object to be processed is compared with the previously stored band gap spectral reflectance distribution of the reference semiconductor crystal material.
As will be described later, a sample showing a desired semiconductor crystal state is
Since it is known that a certain degree of spectral reflectance distribution is shown, the reference spectral reflectance distribution is compared with the spectral reflectance distribution of the object to be spectrally detected, and the approximation degree of the object The crystallized state, that is, the progress of the laser annealing process can be determined.

As a result of the comparison, when it is determined that the crystallized state of the object to be processed has not reached the standard, the CPU 90 sends a command signal for enhancing the laser irradiation energy to the system, and step S4 At, the laser irradiation energy is adjusted. Note that it is usually preferable that the laser irradiation energy be gradually increased as described above.

The laser irradiation energy can be adjusted by changing the output of the excimer laser source 22, changing the laser irradiation interval in the case of spot irradiation, or driving the reflecting mirror 7a in the XY directions. There is a method of adjusting the moving speed of the driving mechanism 70, and these methods can be adopted individually or in combination to adjust the laser irradiation energy to a desired value.

In accordance with the instruction from step S4, laser irradiation (step-S1) and spectroscopic detection (step-S).
The sequence of 2) and crystal state evaluation (step-S3) is repeated until the crystallized state of the object to be processed reaches the reference stored in the memory 94. Step S3 above
When it is determined that the crystallized state of the object to be processed has reached the reference in step S5, the drive mechanism 70 is driven to scan and irradiate the next irradiation region with the laser. In this way, the sequence from step S1 to step S5 is repeated until it is determined in step S6 that the laser annealing process has been completed for all the regions to be processed.

As described above, according to the method or apparatus for producing a polycrystalline semiconductor thin film using the method for evaluating a semiconductor crystal state related to the present invention, a special and expensive apparatus such as Raman spectrometer is not used, Since it is possible to judge the crystallization state by the spectral reflectance distribution in which the characteristics of the crystallization state of the semiconductor are prominent and to perform feedback control of the laser irradiation energy in real time, it is possible to perform laser annealing processing easily and at low cost. It is possible to manufacture a TFT liquid crystal display with high yield and high throughput.

When the semiconductor crystal thin film manufacturing process is completed by the above sequence, the inside of the vacuum chamber 63 is returned to atmospheric pressure, the gate valve G is opened, and the substrate 20 is transferred to the outside by a transfer mechanism (not shown). Take it out to
Subsequent film formation processing is performed in a semiconductor processing station including a film formation processing station and a lithography station. In this film formation process, LC on the same substrate
In the pixel portion region and the driving portion region of the D substrate, the TFTs forming a part of the pixel unit and the switching elements of the driving portion are integrally formed at the same time by using a mask having a predetermined pattern. Further, in this step, scan electrode wirings connecting the pixel portion and the driving portion are also formed at the same time. Therefore, the conventional L
A complicated drive part L that was necessary in the CD substrate manufacturing process
It is possible to omit the SI chip mounting process and the wiring process.

Next, the laser reflectivity distribution of the semiconductor bandgap, which serves as a reference for carrying out the method and apparatus for evaluating a semiconductor crystal according to the present invention, will be described.

As is well known, the energy band of a silicon crystal has a structure as shown in FIG. 10, and its band gap has a width of about 3.43 eV at the Γ point and about 4.40 eV at the X point. Have A reference semiconductor crystal having the above-mentioned bandgap structure and a film thickness of 500 angstroms is, for example, a rectangular beam having dimensions of 0.65 (cm) × 0.65 (cm) = 0.43 (c).
m ² ) can be irradiated with a laser having a laser energy of, for example, 400 mj through a transmission window having an optical transmittance of 75%.

FIG. 11 shows the bandgap spectral reflectance distribution when the reference semiconductor crystal is irradiated with the laser under the above conditions. As shown in the figure, the band gap spectral reflectance distribution of the reference semiconductor crystal has a wavelength of around 284 nm and 364 n.
There are peak values at two locations near m, and the respective peak values correspond to points X and Γ of special points in the first Brillouin zone of the silicon crystal.

For reference, the band gap spectral reflectance distribution of amorphous silicon is shown in FIG. As shown in the figure, it is known that the band gap spectral reflectance distribution of amorphous silicon shows a downward-sloping distribution with no peak value.

As described above, as can be easily understood by comparing FIG. 11 and FIG. 12, since the contour shape of the bandgap spectral reflectance distribution of the reference semiconductor crystal has a unique shape, such band The first information regarding the gap spectral reflectance distribution is stored as the reference information in the memory 94 in advance, and the second information regarding the band gap spectral reflectance distribution acquired by the spectroscope 86 in real time during the annealing treatment of the object to be processed. By comparing the information and the information by a known method by a comparator provided in the spectroscope 86,
The crystallization state of the object to be processed can be known in real time.

For example, when the laser irradiation energy transmitted from the laser source 22 is a value insufficient for promoting crystallization of the object to be processed, such as 200 mj, the reflected light from the object to be processed is As shown in FIG. 13, the bandgap spectral reflectance distribution detected from the sample has a curved contour shape with an unclear peak value and rising to the right. On the other hand, if the laser irradiation energy transmitted from the laser source 22 is too strong for semiconductor detection, such as 600 mj, the band detected from the reflected light from the object to be processed is shown. As shown in FIG. 14, the gap spectral reflectance distribution has a contour shape in which the entire film is damaged and the entire spectral reflectance distribution is shifted downward. It is considered that such a phenomenon occurred as a result of the formation of silicon oxide on the surface.

Therefore, when the bandgap spectral reflectance distribution as shown in FIG. 13 is spectrally detected, the laser irradiation energy should be gradually increased so as to approach the reference distribution as shown in FIG. The system can be feedback controlled in real time. Therefore, it is preferable to control the laser irradiation energy before the film damage as shown in FIG. 14 occurs. Further, if the band gap spectral reflectance distribution as shown in FIG. 14 is spectrally detected, the sample can be extracted as a defective product.

However, as described above, it is usually preferable to control so that the laser irradiation energy is gradually increased, that is, the distribution shown in FIG. 13 approaches the distribution shown in FIG. This is because when the laser irradiation energy more than necessary is suddenly applied, the hydrogen contained in the amorphous silicon film may be blown out at once and damage the silicon film, and the sample becomes a defective product. .

Further, the comparison between the reference reflectance distribution and the reflectance distribution of the object to be processed cannot be a perfect match due to the characteristics of the analysis method. Is performed by the method of seeing. For example, when comparing the peak values at the X point (about 284 nm) and the Γ point (about 364 nm), it is possible to allow an error of about ± 20 nm. Further, the crystallization state of the object to be processed is evaluated by tracing the contour shape of the spectral reflectance distribution using a technique well known in the figure recognition field, and comparing the data with a certain degree of tolerance. It is also possible.

In the above, in the present invention, the irradiation method of the laser beam is not limited to the above-mentioned embodiment, and for example, after irradiating one pulse at a certain irradiation energy in an island shape,
A method of sequentially irradiating these irradiation regions with a larger irradiation energy may be used.

The laser light irradiation method is, for example, an optical system in which a large number of laser light beams are arranged in a line at intervals and the laser light beams are simultaneously irradiated to the amorphous silicon film. A large number of island-shaped other crystal regions may be simultaneously formed. Furthermore, FIG.
As shown in (a), the amorphous semiconductor film 2 may be irradiated with a band-shaped laser beam having a cross-sectional shape of, for example, about several millimeters × 100 millimeters from the laser light irradiation section 3, or alternatively, FIG.
As shown in (b), laser light having a L-shaped cross section may be irradiated. That is, in the present invention, irradiating a pulse of laser light in an island shape corresponds to both a case of forming a plurality of island-shaped irradiation areas and a case of forming one island-shaped irradiation area. The shape and size may be selected by appropriately designing the optical system.

Then, as shown in FIGS. 15 (a) and 15 (b), if a wide irradiation area 51 is formed and a plurality of driving circuit parts such as gate drivers or source drivers are formed therein, the optical system is designed. This is preferable because it is easy, and the position of the irradiation region of the laser beam and the mask mask pattern of lithography can be easily matched, and the throughput is increased.

In the present invention, the switching element for controlling the on / off of the voltage to the pixel electrode is not limited to the TFT, and the amorphous semiconductor film is polycrystallized to perform switching on the polycrystallized film. Elements may be created.

Next, an example of a manufacturing apparatus suitable for mass-producing LCD substrates by laser annealing will be described with reference to FIG. This manufacturing system systematically integrates a plurality of processing units and substrate loading / unloading units into a single system, so that multiple processes in the manufacturing process of a liquid crystal display substrate can be carried out in this system as a whole. Is configured. Input / output area 30 in the figure
The loading unit (substrate loading unit) and the unloading unit (substrate unloading unit) included in 7 are cassette 303,
This is a part for loading and unloading 306 with the outside, and for example, a cassette stage is arranged. Here, the cassette is a container for accommodating, for example, 25 substrates to be processed, and the cassettes 303 and 306 are staged so that the substrates 302 and 305 to be processed are vertically arranged with a horizontal interval. Placed on.

A first transfer means having two upper and lower transfer arms 311 and 312 for transferring the substrate to be processed in the input / output area 307 so as to be rotatable around the Z axis and along the X stage 314. The upper transfer arm 311 is used to take out the unprocessed substrate 302 from the cassette 303 and deliver it to the transfer means 322 in the processing unit described later, and the lower transfer arm 312. The processed substrate 305 after processing to the cassette 30
Used to deliver within 6. The X stage 31
4 is a cassette 303, along the Y stage 315 extending in the Y direction between the loading section and the unloading section.
It is configured to move between a row of 305. Positioning means 316 is provided on the X stage 311 for aligning the orientation and center position of the target substrate so that the target substrate is placed in a predetermined orientation in the processing section.

The processing section 300 adjacent to the input / output area 307
A second transport means 322 that moves along a transport path 325 extending in the X direction is provided inside. This transport path 3
25 is common to each processing device described later, and the transfer means 322 is movable in the Y direction, movable in the Z axis direction (vertical direction), and movable around the Z axis on the moving stage 324. Transport arm 32 that can rotate (rotate in θ direction)
3 is provided and configured. A plurality of processing devices, for example, a preheating device 319, a film forming device 320, a cooling device 321, and a laser annealing device 318 are provided on both sides of the transport path 325.
And a cooling device 317 are provided. The transport means 3
Reference numeral 22 is for transferring a substrate to be processed between these processing devices and the alignment means 316.

Further, the input / output unit 307 and the processing unit 300
Is at atmospheric pressure or an atmosphere at atmospheric pressure or higher with an inert gas such as N ₂ gas. Since a vacuum chuck can be used with such a gas atmosphere, a vacuum chuck is provided on the rotary stages of the transfer arms 311, 312, 323 and the alignment means 316.
The substrate to be processed can be adsorbed.

The operation of the apparatus shown in FIG. 16 will be described. For example, a cassette 303 containing 25 processed substrates, for example, soda glass substrates 302 whose surfaces have been cleaned, is transferred into the input / output section 307, and then the transfer arm is carried. The substrate 302 to be processed is taken out from the cassette 303 by 311. The substrate 302 to be processed is aligned by the alignment means 316 and then transported to the preheating device 319 via the transport means 322, where the temperature is set to a temperature near the amorphous silicon film formation temperature of 600 ° C., for example, 350 to 400 ° C. Be heated. This preliminary heating is performed in order to form a film quickly in the next step and to obtain an amorphous silicon film of good quality with few defects. Next, the substrate to be processed is transferred to the film forming apparatus 320, and after being evacuated to a predetermined degree of vacuum in the film forming apparatus 320, a process gas is supplied and plasma is generated using, for example, high frequency power, and the temperature is increased to, for example, about 600 ° C. On the heated substrate to be processed, for example, 300 to
An amorphous silicon film having a thickness of 1500 Å is obtained. Note that, for example, a load lock chamber (not shown) is connected to the film forming apparatus 320, and the substrate to be processed is carried in and out through the load lock chamber. Further, the substrate to be processed is cooled to a temperature of, for example, 400 ° C. or lower by the cooling device 321, and then, in the laser annealing device 318, a laser beam is applied to each predetermined region of the amorphous silicon film on the substrate to be processed as described above. Pulse is, for example, 30 to
The substrate to be processed is irradiated 1000 times to form island-shaped regions of the polysilicon film.
After being cooled to a temperature of 0 ° C. or lower, the conveying means 322 to the aligning means 316 and the conveying arm 312.
It is conveyed into the cassette 305 via.

According to such a device, a series of processing devices are arranged in one device and a common transfer path 325 is provided.
Since a plurality of processing devices are arranged on both sides of the above, it is possible to easily cope with an increase in the number of processes and the number of substrates to be processed by simply increasing the number of processing devices. Further, it is possible to easily cope with an arbitrary combination of a plurality of processes by changing the transfer route of the substrate to be processed between the plurality of processing apparatuses. Note that the plurality of processing devices may be processing devices that perform different processes, or may be processing devices that perform the same process.

Further, since the carrier passage and the like in the manufacturing apparatus are in an inert gas atmosphere, the growth of the natural oxide film and the alteration of the film quality are suppressed, and the surface cleaning step is not necessary. In addition, since the substrate to be processed is transferred in the gas atmosphere at atmospheric pressure or higher, a vacuum chuck can be used for the transfer arm and the like, and therefore reliable holding and high-speed transfer with little displacement can be performed. It can be constructed at low cost.

In the above, an example of the apparatus configuration for making the inside of the manufacturing apparatus into the inert gas atmosphere as described above will be described with reference to FIG. 17. The housing 402 is installed in a clean room, and the cassette as described above is installed. A loading section and an unloading section for storing the above, a transfer area of each processing apparatus and a common transfer unit, and the like are stored.

A gas supply source 403 of an inert gas such as N ₂ gas is provided outside the housing 402.
A mass flow controller 404 and a gas pipe 404 via a valve are connected to the gas supply source. The outlet of the gas pipe 404 communicates with a plurality of gas supply ports 407 on the housing 402, and the gas supply ports 407 are connected to each other.
The filter 4 for removing particles forming the ceiling portion of the housing 402 is provided on the lower side of the housing via the fans 408, respectively.
09 are provided. The filter 409 and the fan 4
The upper and lower positions of 08 may be reversed.

A large number of holes 412 are formed in the bottom surface 411 of the housing 402, and a fan 413 is provided on the lower side thereof to exhaust N ₂ gas in the housing 402 to the space 400 on the lower side. It is like this.
Exhaust means 415 for exhausting air to the outside of the factory is connected to this space 400 via an exhaust port 414, while the suction port 4
16, an air supply tube 418 equipped with a fan 417 on the way
Are in communication. The discharge side of the air supply pipe 418 communicates with the gas supply port 7. Therefore, fresh N ₂ gas is replenished in the housing 402 and circulates while forming a substantially vertical downward laminar flow. A pressure controller 420 is provided in the exhaust control system of this embodiment, and the pressure controller 420 is based on the output value and the set pressure value of the pressure detection unit 419 that is installed in the housing 402 and detects the gas pressure. The flow rate controller 405 and the exhaust means 415 are controlled so that the pressure in the housing 402 is adjusted to a predetermined value, that is, the pressure is neither too high nor too low.

The housing 402 has a door 4 for loading or unloading the cassette.
30 are provided. The pressure in the housing 402 is
The pressure is always set to be higher than that of the outside, and therefore, when the door 430 is opened and the cassette is carried in and out, it is possible to prevent the outside air from entering the housing 402, that is, the particles.

[0087]

As described above, according to the first and second aspects of the invention, the amorphous semiconductor film is polycrystallized by irradiating the amorphous semiconductor film with a pulse of laser light, and the drive circuit portion is provided in the irradiation region. Since at least the semiconductor element is formed, the entire irradiation region is uniformly and favorably polycrystallized, and therefore, good performance can be obtained without variation in any driving circuit portion.
As a result, in the manufacture of the LCD substrate, it is possible to realize the generation of the drive circuit portion using the amorphous semiconductor film and the wiring by the film formation process of the switching element in the drive circuit portion and the pixel region, so that the pixel region and the drive region are separated from each other. Realized in the same process,
The LCD substrate is easy and inexpensive to manufacture.

According to the third aspect of the invention, the crystallized state of the amorphous semiconductor can be evaluated in real time by a simple and low-cost method without using a special and expensive optical system. . According to the method for manufacturing a semiconductor crystal thin film (the invention of claim 4) and the apparatus (the inventions of claims 5 and 6) using the above evaluation method, the crystallization treatment of the amorphous semiconductor is performed by the laser annealing method. However, the crystallization state of the amorphous semiconductor can be evaluated in real time by a low-cost method, and the crystallization process can be feedback-controlled in real time based on the evaluation result, improving product yield and throughput. Can be improved.

According to the inventions of claims 7 to 10, it is possible to easily cope with an increase in the number of processes and the number of substrates to be processed, a liquid crystal display substrate can be manufactured with high throughput, and a vacuum chuck can be provided. Since it can be used, the substrate to be processed can be reliably transported at high speed.

[Brief description of drawings]

FIG. 1 is a perspective view showing steps of a method for manufacturing a liquid crystal display substrate according to an embodiment of the present invention.

FIG. 2A is a plan view showing a relationship between a laser light irradiation region and a drive circuit portion formation region.

FIG. 2B is a plan view showing a part of a drive circuit section and wiring.

FIG. 3 is a vertical cross-sectional side view showing an example of a laser annealing apparatus used in an example of the present invention.

FIG. 4 is a perspective view showing a laser annealing apparatus used in an example of the present invention.

FIG. 5 is a block diagram showing a laser emitting unit and a semiconductor crystal evaluation unit of the same apparatus.

FIG. 6 is a characteristic diagram showing a relationship between laser beam irradiation energy density and hydrogen release amount in a hydrogenated amorphous silicon film forming process.

FIG. 7 is a characteristic diagram showing a relationship between laser beam irradiation energy density and hydrogen release amount in hydrogenated amorphous silicon film formation processing.

FIG. 8 is a diagram for explaining the relationship between the number of laser shots and polycrystallization of a single crystal.

FIG. 9 is a flowchart for explaining a semiconductor evaluation method according to an example of the present invention.

FIG. 10 is a structural diagram showing an energy band structure of a silicon crystal.

FIG. 11 is a graph showing a bandgap spectral reflectance distribution of a reference semiconductor crystal.

FIG. 12 is a graph showing a bandgap spectral reflectance distribution of amorphous silicon.

FIG. 13 is a graph showing a bandgap spectral reflectance distribution when laser irradiation energy is insufficient.

FIG. 14 is a graph showing a bandgap spectral reflectance distribution when laser irradiation energy is excessive.

FIG. 15 is an explanatory diagram showing a laser light irradiation region according to another embodiment of the present invention.

FIG. 16 is a plan view showing an apparatus for manufacturing a liquid crystal display substrate according to an embodiment of the present invention.

FIG. 17 is a cross-sectional view showing an apparatus for manufacturing a liquid crystal display substrate according to another embodiment of the present invention.

FIG. 18 is a configuration diagram schematically showing the structure of a liquid crystal display substrate.

FIG. 19 is a perspective view showing a liquid crystal panel.

FIG. 20 is an explanatory view showing the relationship between the overlapping state of laser light pulses and the electric field efficiency mobility in the conventional method.

[Explanation of symbols]

 1 Glass Substrate 2 Amorphous Silicon Film 3 Laser Light Irradiation Sections 4, 41, 42 Drive Circuit Section 5 TFT 50 Pixel Region 63 Vacuum Chamber 7 Laser Light Irradiation Section 70 Moving Mechanism 313 First Transfer Means 322 Second Transfer Means 325 Conveyance path 317-321 Processing device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location H01L 21/336

Claims (10)

[Claims] 1. A method of manufacturing a liquid crystal display substrate, comprising: a plurality of switching elements arranged in a pixel region on a substrate; and a plurality of drive circuit units for driving the switching elements, the method comprising: A step of forming an amorphous semiconductor film, and irradiating the amorphous semiconductor film with a pulse of laser light intermittently to polycrystallize the irradiated region to form a polycrystalline island in the amorphous semiconductor film. A step of forming a rectangular region, a step of forming a drive circuit portion in the polycrystalline island region having a polycrystalline region of this region as a semiconductor region, and a part of the amorphous semiconductor film being a semiconductor region, And a step of forming a switching element electrically connected to the drive circuit section in the pixel region, the method comprising: 2. A method of manufacturing a liquid crystal display substrate comprising a switching element arranged in a pixel region on a substrate and a shift register for driving the switching element, the amorphous semiconductor being on the substrate. A step of forming a film; a step of irradiating the amorphous semiconductor film with a pulse of laser light in a plurality of islands to polycrystallize the amorphous semiconductor film; and an irradiation region of the pulse of laser light And a step of forming a wiring layer for electrically connecting the divided shift registers and between the divided shift registers and the switching element to each other. Of at least the transistor
A method for manufacturing a liquid crystal display substrate, characterized in that the liquid crystal display substrate is arranged in an irradiation region of a pulse of light. 3. A method for evaluating the crystallization state of a semiconductor, which comprises irradiating a reference semiconductor crystal material in an optimum crystallization state with laser light, spectrally detecting the reflected light, and detecting the detected value. A step of pre-storing the first information on the bandgap spectral reflectance distribution of the reference semiconductor crystal material obtained above, irradiating the evaluation region of the semiconductor to be evaluated with laser light,
A step of spectrally detecting the reflected light, obtaining second information regarding the bandgap spectral reflectance distribution of the evaluation region from the detected value, and comparing the first information and the second information, A method for evaluating a semiconductor crystal, which comprises the step of evaluating the crystallized state of the semiconductor according to the degree of approximation. 4. A method for producing a semiconductor crystal thin film while crystallizing an amorphous region of an object to be processed by laser annealing and evaluating the crystallized state thereof, which is a reference semiconductor in an optimum crystallized state. Irradiating the crystal thin film with laser light, spectrally detecting the reflected light, and pre-storing first information regarding the bandgap spectral reflectance distribution of the reference semiconductor crystal thin film acquired from the detected value; While performing the annealing process, the reflected light from the evaluation region of the object to be processed is spectrally detected, and the second information regarding the band gap spectral reflectance distribution of the laser irradiation region of the object to be processed is acquired from the detected value. And a step of comparing the first information with the second information and adjusting laser irradiation energy so that the degree of approximation falls within a predetermined range. A method for manufacturing a semiconductor crystal thin film. 5. A processing chamber, means for supporting an object to be processed having a semiconductor crystal thin film in the processing chamber, and laser irradiation means for annealing the thin film by irradiating the semiconductor crystal thin film with laser light. Storage means for pre-storing first information on the bandgap spectral reflectance distribution regarding the reference semiconductor crystal thin film in the optimum crystallization state, and the laser irradiation means irradiates the processed surface of the object to be processed, Laser spectroscopic detection means for spectroscopically detecting the reflected light reflected from the processing surface to obtain second information on the bandgap spectral reflectance distribution of the laser irradiation region of the processed surface, and the laser spectroscopic detection means. A comparison and evaluation means for comparing and evaluating the acquired second information with the first information stored in the storage means; Based on the evaluation signal output from
Laser irradiation energy adjusting means for adjusting the laser irradiation energy of the laser irradiation means so that the degree of approximation between the first information and the second information falls within a predetermined range. And an apparatus for manufacturing a semiconductor crystal thin film. 6. A step of forming an amorphous semiconductor film on a substrate, and the amorphous semiconductor film is intermittently irradiated with a pulse of laser light to polycrystallize the irradiated region to form an amorphous state. Forming a polycrystalline island region in the crystalline semiconductor film, forming a drive circuit portion in the polycrystalline island region having a polycrystalline region of this region as a semiconductor region, and The step of forming a switching element electrically connected to the drive circuit section in a part of the semiconductor region in the pixel region, and irradiating the reference semiconductor crystal material in the optimal crystallized state with laser light and reflecting the reflected light In a step of pre-storing first information about the bandgap spectral reflectance distribution of the reference semiconductor crystal material obtained by spectral detection of the reference semiconductor crystal material, and a step of forming the polycrystalline island region. Of laser light from a high quality semiconductor film A step of spectrally detecting light and acquiring second information regarding the bandgap spectral reflectance distribution of the evaluation region from the detected value, the first information and the second information are compared, and the degree of approximation thereof is compared. And a step of evaluating the crystallized state of the semiconductor according to the above. 7. A substrate carry-in section on which a cassette containing a plurality of unprocessed substrates to be processed is placed, alignment means for aligning the substrates to be processed, and both sides of a common transport path. A plurality of processing devices, a first transfer unit that transfers a substrate to be processed in a cassette placed in the substrate loading unit to an alignment unit, and a first transfer unit that moves along the common transfer path A second means for transporting the substrate to be processed between the aligning means and each of the processing devices
The substrate loading unit, the alignment unit, the first transport unit and the second transport unit are provided in the atmosphere or in a non-oxidizing gas atmosphere having a pressure higher than atmospheric pressure. An apparatus for manufacturing a liquid crystal display substrate, which is characterized in that 8. The plurality of processing devices include a preheating device for preheating a substrate to be processed, a film formation processing device for forming an amorphous semiconductor film on the substrate to be processed, and a cooling device for cooling the substrate to be processed. The apparatus for manufacturing a liquid crystal display substrate according to claim 7, further comprising: an apparatus and a laser annealing apparatus for annealing the amorphous semiconductor film on the substrate to be processed with laser light to polycrystallize it. 9. A substrate unloading unit, on which a cassette for storing a plurality of processed substrates to be processed is placed, is provided in a transfer area of the first transfer unit, and the alignment unit is arranged by the first transfer unit. 9. The apparatus for manufacturing a liquid crystal display substrate according to claim 7, wherein the substrate to be processed is transferred to a cassette mounted on the substrate unloading section. 10. The second transfer means is a movable stage movable along a transfer path extending in the X-axis direction, and is provided on the movable stage to rotate in the θ direction, move forward / backward in the Y-axis direction and Z. 10. The liquid crystal display substrate manufacturing apparatus according to claim 7, further comprising a transfer arm that is movable in the axial direction.