JP2002305208A - Method of manufacturing semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of laser annealing which charges sufficient energy of a laser into a source region and a drain region but will not charges energy more than necessary into a channel region or a low dose region provided in a Gold structure of TFT at the same time, in the case of applying a laser to a top gate type of TFT in the process of adding and activating a dopant in a semiconductor film grown on a glass substrate. SOLUTION: A laser is also applied to the vicinity of a channel formation region if it is applied to a glass board 10 from its rear where a semiconductor film is not grown, using the second higher harmonics of a transparent YAG laser or the like, however here if the worker seeks to give sufficient energy to the source region and the drain region 1031, energy adds to the channel region 1032 more than necessary, which lowers the performance of the TFT, so strong energy is given to only the source region and the drain region by applying the laser having passed the semiconductor film again from the surface side of the glass substrate, using a mirror or the like 106.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor device manufactured by activating a dopant added to a semiconductor film formed on a substrate by a laser or an intense light equivalent thereto. The semiconductor device generally refers to a device that can function by utilizing semiconductor characteristics,
For example, an electro-optical device typified by a liquid crystal display device, an electric device including the electro-optical device as a component, a light emitting device, and the like are also included in the category of the semiconductor device.

[0002]

2. Description of the Related Art There is a wide variety of techniques for performing laser annealing on a semiconductor film formed on an insulating substrate such as glass to crystallize or improve crystallinity or activate a dopant added to the semiconductor film. Has been studied. A silicon film is often used as the semiconductor film.

A glass substrate is often used as the insulating substrate. For a glass substrate, for example, 600 mm × 720
It can be processed into a large area substrate having a size of mm × 0.7 mm. A quartz substrate or the like is used other than the glass substrate, but it is difficult to increase the area of the quartz substrate. Although the advantage of using a glass substrate is great, there is a problem that the melting point of the glass substrate is lower than that of the quartz substrate. Since a relatively high temperature is required for annealing a semiconductor film, deformation of a glass substrate during annealing has been a problem. Laser annealing of a semiconductor film has been devised to solve this problem. Since a laser can emit very strong energy in a short time, an object can be heated in a non-equilibrium manner. Therefore, without increasing the temperature of the glass substrate
Only the temperature of the semiconductor film can be increased. That is, it is preferable to use a laser for annealing the semiconductor film formed on the glass substrate.

[0004] The crystalline semiconductor film obtained by the above technique is made of many crystal grains and is called a polycrystalline semiconductor film. The polycrystalline semiconductor film is compared with the amorphous semiconductor film,
Has a very high mobility. For this reason, when a polycrystalline semiconductor film is used, for example, an active matrix type liquid crystal display device (a pixel driving device) cannot be realized with a semiconductor device manufactured using a conventional amorphous semiconductor film. And a semiconductor device in which a thin film transistor (TFT) for a driver circuit is manufactured. As described above, a polycrystalline semiconductor film is a semiconductor film having extremely high characteristics as compared with an amorphous semiconductor film.

On the other hand, in the crystallization step of the amorphous semiconductor film, a method which can be performed by a heat treatment at a relatively low temperature has been devised.
Details of the above method are described in JP-A-7-183540. Here, the method will be briefly described. First, a small amount of an element such as nickel, palladium, or lead is added to an amorphous semiconductor film. As a method of addition, a plasma treatment method, an evaporation method, an ion implantation method, a sputtering method, a solution coating method, or the like may be used. After the addition, the amorphous semiconductor film is heated in, for example, a nitrogen atmosphere at 550 ° C. for 4 hours to obtain a polycrystalline semiconductor film. The optimum heating temperature and heating time for crystallization depend on the amount of the element added and the state of the amorphous semiconductor film. The example of the method of crystallizing an amorphous semiconductor film by heating has been described above.

As described above, crystallization by laser annealing can give high energy only to an amorphous semiconductor film without increasing the temperature of the substrate so much. , Plastic substrates and the like. The laser annealing step is also used in the step of activating the dopant added to the semiconductor film. This step is often performed by thermal annealing.

[0007] In the current mass production process, a laser used for laser annealing is an excimer laser. Excimer lasers are used in the mass production process because they have a large output due to a pulse oscillation type and have an extremely high absorption coefficient with respect to a silicon film often used for a semiconductor film. On the surface to be irradiated with a pulsed laser beam having a large output,
It is shaped by an optical system so that it becomes a square spot of m square or a linear shape with a length of 10 cm or more, and it is scanned with a laser beam
The method of performing laser annealing (or by moving the irradiation position of the laser beam relative to the irradiation surface) is preferably used because of high productivity and excellent industrial properties.

In particular, when a laser beam whose laser beam has a linear shape on the surface to be irradiated (hereinafter, referred to as a linear beam) is used, a case where a spot-shaped laser beam that needs to be scanned back, forth, left and right is used. In contrast, the laser beam can be irradiated on the entire surface to be irradiated by scanning only in a direction perpendicular to the linear direction of the linear beam, so that productivity is high. Scanning is performed in a direction perpendicular to the line direction because it is the most efficient scanning direction. Due to this high productivity, it is now becoming the mainstream for laser annealing to use a linear beam obtained by processing a laser with high output of pulse oscillation by an appropriate optical system. Linear beam is especially 600mm in size
This is effective in a mass production process using a large-area substrate such as × 720 mm × 0.7 mm.

[0009]

An object of the present invention is to activate a dopant added to a semiconductor film using a laser. When doping a semiconductor film, for example,
When manufacturing a top gate type TFT, doping is often performed using the gate electrode as a mask. Doping is mainly performed by ionizing the dopant and applying an accelerating voltage, thereby giving a speed to the ions and implanting the ions into the semiconductor film. After the doping, annealing by laser or heat is performed to activate the dopant in the semiconductor film. Alternatively, a method using both laser and heat is also used.

Generally, activation of a dopant by a laser is superior to activation of a dopant by heat in terms of lowering resistance. However, for example, in the case of activating a dopant with a laser for a top gate type TFT, a portion of the semiconductor film located below or near the gate electrode is shaded, so that the laser is not irradiated there. There was also a disadvantage. Particularly, in consideration of the reliability of a TFT as a semiconductor element, a low-concentration dopant is often added below the gate electrode. Such a structure is called Gold (Gate-Drain Overlapp
(ED LDD) structure. In this case, it is difficult to irradiate the dopant below the gate electrode with laser. In this case, if the laser is irradiated from the back side of the glass substrate, it is possible to irradiate the laser to the dopant below the gate electrode.However, since an excimer laser generally used for a semiconductor film does not transmit much through the glass, Poor energy efficiency and impractical. Note that, in this specification, the back surface of a glass substrate refers to a surface on which a semiconductor film is not formed. In this specification, the surface of a glass substrate refers to a surface on which a semiconductor film is formed. Even if there is no portion to which the low concentration dopant is added (hereinafter referred to as a low dose region), a high electric field is generated between the doped region and the undoped channel region. It is important to irradiate a laser beam with appropriate energy in order to reduce the defect density in this portion.

[0011] The transmittance of ultraviolet light such as that generated by an excimer laser to glass is relatively low, while visible light is almost transparent to glass. Therefore, it is easy to irradiate a visible light laser from the back surface side of the glass substrate to anneal the entire semiconductor film. However,
Generally, a visible light laser also has a light-transmitting property with respect to a semiconductor film, and is partially absorbed by the semiconductor film as heat, but the other part is transmitted as light. Due to this property of visible light, for example, in the process of manufacturing a top gate type TFT, when laser irradiation is performed from the back side of the glass substrate, the channel region located below the gate electrode with high light reflectance, The energy of the laser to be irradiated is changed between the source region and the drain region where the substance with a high rate is not disposed above. That is, there is no medium that reflects light particularly above the source region and the drain region, but above the channel region,
Since the gate electrode is located above the other low-dose regions (regions provided when the structure of the TFT is referred to as Gold), light reflected from the gate electrode is again reflected in the channel region and the above-described region. Since the low dose regions are irradiated, more energy is applied to these regions than to the source and drain regions.
Therefore, if energy for sufficiently activating both the source region and the drain region is applied, energy is applied more than necessary to a channel region and the like located below the gate electrode, and the crystal state may be deteriorated.

An object of the present invention is to supply sufficient laser energy to a source region and a drain region,
An object of the present invention is to provide a laser annealing method in which unnecessary energy is not applied to a channel region or a low-dose region provided in a Gold TFT.

[0013]

In order to achieve the above object, the present invention provides a laser having high transparency to a substrate or an intense light equivalent thereto (hereinafter, these are collectively referred to as light). Is irradiated from the back surface side of the substrate on which the semiconductor film is formed, and the light transmitted through the semiconductor film is reflected by a reflector disposed on the front surface side of the substrate. The method is characterized in that the drain region is irradiated with reflected light. The present invention provides a method devised based on such an idea. The present invention is excellent in productivity because it can be effectively applied to a large-area substrate. In this embodiment, the intense light corresponding thereto refers to a halogen lamp, a metal halide lamp, a high-pressure mercury lamp, a high-pressure sodium lamp, a xenon lamp, or the like. As the substrate, it is preferable to use a quartz substrate, a glass substrate, or a plastic substrate having high transmittance to visible light.

Specifically, for example, when activating a source region and a drain region of a top gate type TFT provided on a surface of a glass substrate and other low dose regions,
After a region to which a dose is added is formed by self-alignment using the gate electrode as a mask, a laser beam is irradiated at an appropriate intensity from the back surface of the glass substrate. This process is shown in FIG.
Explanation will be made along (a). In FIG. 1A, a glass substrate 10
1 and the base film 102 have a light-transmitting property with respect to the laser beam used in the activation step, so that sufficient laser energy can be applied to the active layer 103 even when the laser beam is incident from the glass substrate 101 side. Can be. N-type or P-type impurities are added to the source region and the drain region 1031 of the active layer 103 using the gate electrode 105 as a mask, and a channel region 1032 is formed between the source region and the drain region 1031. . Active layer 10
There is a gate insulating film 104 between the gate electrode 3 and the gate electrode 105. In order to form a structure called Gold, a low dose region may be provided below the gate electrode at both ends of the channel region 1032 in some cases.

In the state shown in FIG. 1A, for example, when a laser beam of visible light is applied to the active layer 103 from the back side of the glass substrate 101, a part of the laser beam is absorbed by the active layer 103, but the other layer is absorbed. The part is transparent. Part of the transmitted light is reflected by the gate electrode 105 and is again returned to the channel region 1032.
Irradiated. Another part of the transmitted light passes through the source region and the drain region 1031 and passes out of the semiconductor film as it is. When the emitted laser beam is again irradiated on the active layer 103 by the reflector 106, the gate electrode 105 serves as a mask, so that only the source region and the drain region 1031 are irradiated with the laser beam, and the channel region 1032 is irradiated with the laser beam. No beam is emitted.

This makes it possible to irradiate the source region and the drain region with the same energy as that of a region such as a channel region located below the gate electrode. In the case of activating the source region and the drain portion of the bottom gate type TFT and other low dose regions, the object of the present invention can be achieved by performing laser annealing with the same concept. FIG. 1B shows a diagram of a bottom gate type TFT. Glass substrate 10
7, a gate electrode 108 is formed, and a gate insulating film 109 is formed thereon. Further thereon, a semiconductor film 110 is formed, and a channel region 1102 is provided immediately above the gate electrode 108, and a source region to which an impurity element imparting N-type or P-type is added is provided on both sides of the channel region 1102. And a drain region 1101.
In order to add a dopant to the source region and the drain region 1101, a mask may be formed immediately above the gate electrode, and then ion doping or ion implantation may be performed. Thereafter, the mask is removed. In this state, by irradiating a laser beam from the front side of the glass substrate and disposing the reflector 111 on the back side of the glass substrate, the same effect as that obtained by the top gate can be obtained.

It is preferable that the reflectors 106 and 111 be arranged at a certain distance from the glass substrate. In particular, when a laser is used as the light source, the laser beam 1 emitted from the back side of the glass substrate and the laser beam 2 emitted from the front side of the glass substrate interfere with each other, and the uniformity of the energy distribution deteriorates. Therefore, it is preferable that the optical path difference between the laser beam 1 and the laser beam 2 be equal to or longer than the coherent length of the laser. Also, if the reflected light from the reflector completely coincides with the optical path of the incident light, the laser beam may return to the laser oscillator and damage the laser oscillator.
It is important not to make the optical path of the incident light coincide with the optical path of the reflected light by devising, for example, configuring the reflector with two mirrors. Even if the irradiation positions of the reflected light and the incident light on the glass substrate are not completely matched, the essence of the present invention is not affected at all.
Use of only one reflector may be used.

If the energy of the laser beam alone is not sufficient at this time, it is preferable to perform the heating while heating the glass substrate with a lamp or a heater. For example, at this time, the heating means is arranged near the glass substrate. The presence of the heating means makes it possible to make up for the shortage of energy of the laser beam, so that when a linear beam is used, the length of the linear beam can be made longer. As a result, the area that can be laser-annealed at a time is increased, so that a substrate having a larger area can be efficiently processed. Alternatively, when the energy density of the light reflected from the reflector on the substrate surface is insufficient, the reflector may be a concave mirror to increase the energy density of the laser beam on the substrate surface. Further, a concave mirror may be used in combination with a lamp or a heater.

Next, an apparatus for realizing the laser irradiation method of the present invention will be described. Assuming that the board is installed horizontally, the method of irradiating light from the back side of the board is:
There is a method in which the substrate is turned upside down and light is irradiated from above, or a method in which light is irradiated from below the substrate. The method of turning the substrate upside down is not preferable because it greatly complicates the apparatus and lowers the productivity. Therefore, it is preferable that the surface of the substrate is directed upward and light is irradiated from below the substrate. In order to realize such an apparatus configuration, for example, the stage on which the substrate is disposed is preferably transparent to light. Alternatively, a gap may be provided in the stage on which the substrate is arranged, and light may be incident from the gap. In this case, in order to send the substrate relatively to light, the substrate may be sent using a method such as a belt conveyor system. At this time, the light used is preferably a linear beam because the gap can be elongated. That is, since the deflection of the substrate due to the provision of the gap in the stage is minimized, the deviation of the focus position of the linear beam is minimized. In particular, when a glass substrate having a large area is used, the deflection of the substrate is not negligible, so that it is necessary to adopt a device configuration for suppressing the deflection of the substrate. In general, since the linear beam is very thin, the energy density fluctuates greatly even if the focus position deviates by only a few mm.
It is necessary to keep it below.

The present invention is enumerated below. One aspect of the present invention is to form a semiconductor film on a surface of a substrate, form an insulating film on the semiconductor film, form a gate electrode on the insulating film,
An impurity element is added to the semiconductor film using the gate electrode as a mask, a first light is irradiated from the back surface side of the glass substrate, a second light is irradiated from the front surface side of the substrate, and the second light is irradiated. Is a method for manufacturing a semiconductor device, in which part of the first light is light transmitted through the substrate and the semiconductor film and reflected by a reflector provided on a front surface side of the substrate.

Another aspect of the present invention is to form a semiconductor film on a surface of a substrate, form an insulating film on the semiconductor film, form a gate electrode on the insulating film, and use the gate electrode as a mask. An impurity element is added to the semiconductor film, a first light is irradiated from the back side of the glass substrate, a second light is irradiated from the front side of the substrate, and the second light is irradiated with the first light. Part of the light is light transmitted through the substrate and the semiconductor film and reflected by a reflector provided on the front surface side of the substrate, and is an optical path from the back surface of the substrate to the front surface of the substrate via the reflector. The length is longer than the coherent length of the first light.

Another aspect of the present invention is to form a semiconductor film on a surface of a substrate, form an insulating film on the semiconductor film, form a gate electrode on the insulating film, and use the gate electrode as a mask. An impurity element is added to the semiconductor film, a first light is irradiated from the back side of the glass substrate, a second light is irradiated from the front side of the substrate, and the second light is irradiated with the first light. Part of the light is light transmitted through the substrate and the semiconductor film and reflected by a reflector provided on the front surface side of the substrate, and the second light reaches the reflector from the back surface of the substrate. A semiconductor device that reaches the surface of the substrate by an optical path different from the optical path to the substrate.

In the above invention, the first light and the second light are laser light or light equivalent thereto. This is preferable because the productivity is high.

Further, in the above invention, the first light includes a second harmonic of a YAG laser, a second harmonic of a YLF laser, a second harmonic of a glass laser, a second harmonic of a YVO ₄ laser, and Ar The present invention can be applied to a glass substrate, a transparent substrate, or the like if the light is any one of lasers or a combination thereof.

In the above invention, if the substrate is a glass substrate, a semiconductor device may be manufactured at low cost.

In the above invention, the reflector may be
It is preferable to use a cylindrical concave mirror because the energy density of the second light on the substrate surface can be increased.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In this embodiment, an example will be described in which laser annealing is performed on a TFT to which a low-concentration dopant is added below a gate electrode. In order to irradiate the laser below the gate electrode, as described above, it is effective and effective to irradiate the second harmonic of, for example, a YAG laser from the back surface side of the substrate. Since the second harmonic of the YAG laser is green, it is visible light.

FIG. 2 shows a laser irradiation apparatus according to the present invention. The laser oscillator 201 is a YAG laser. Laser oscillator 2
01 from the optical systems 202 to 20
6 is processed into a linear beam. Since the YAG laser generally has high coherence, in order to make the energy distribution uniform, a method of dividing the laser beam into a plurality of parts and combining them (a well-known method of homogenizing a beam) is used. It is necessary to take measures such as providing optical path differences to each other. The optical path difference may be made, for example, by irradiating a laser beam onto the glass plate 202 processed in a stepwise manner in FIG. The laser beam incident on each step of the staircase has an optical path difference because the refractive index of the glass is greater than one. If the optical path difference is longer than the coherent length of the laser beam, the coherence of the laser beam is greatly reduced, so that a known beam homogenization method can be used. Each of the laser beams having an optical path difference is made incident on a cylindrical lens forming the cylindrical lens array 203, thereby splitting the laser beam. The laser beam emitted from each cylindrical lens is applied to the cylindrical lens 204.
Is combined into one at or near the irradiation surface.
As a result, a linear beam having a uniform energy distribution is obtained.

In order for the laser beam to be incident below the glass substrate, the laser beam passing through the optical system is mirror 20
5 is folded upward. The laser beam is applied to a glass substrate 209 over which a semiconductor film is formed.
The glass substrate 209 is in the state shown in FIG. At this time, in order to secure the energy density of the laser beam, the linear beam may be narrowed by using the condensing cylindrical lens 206. Further, it is not preferable that the laser beam is perpendicularly incident on the glass substrate 209 because reflected light from the back surface of the glass substrate and reflected light from the semiconductor film interfere with each other and cause uneven laser annealing. Therefore, the interference may be suppressed by appropriately changing the angle of incidence of the laser beam by changing the angle of the mirror 205 or the like.

The glass substrate 209 is placed on a stage 207 provided with a gap for passing a linear beam. The transport means 20 such as a belt conveyor is provided on the stage 207.
8 are provided, and serve to send the glass substrate 209 in one direction. Thus, the entire surface of the glass substrate 209 is irradiated with the laser beam. As described above, since a part of the laser beam passes through the glass substrate 209, the transmitted light is turned back by the mirror 210, and
9 is irradiated. Since the laser beam turned back by the mirror 210 is applied to the front of the glass substrate,
The source region and the drain region are irradiated,
It is not irradiated to a channel region or the like provided below the gate electrode. In order to uniformly irradiate the element provided on the glass substrate 209 with a laser beam, the glass substrate 209 is moved by the transport means 208 while irradiating the laser beam, and the entire surface of the glass substrate 209 is irradiated with the laser beam. To do.

The laser annealing method has been described above. Next, a specific method for manufacturing a TFT will be described.

A method for manufacturing an active matrix substrate composed of a TFT in which a low-dose dopant is added below a gate electrode will be described with reference to FIG. In this embodiment, a substrate 2 made of Corning # 1737 glass is used.
11 is used. Note that as the substrate 211, another glass substrate or a quartz substrate may be used. Further, a plastic substrate having heat resistance that can withstand the processing temperature of the present embodiment may be used. It is important that the substrate 211 has high translucency with respect to the second harmonic of YAG.

First, a base film 212 made of an insulating film is formed on a substrate 211. As the base film 212, an insulating film containing silicon such as a silicon oxide film or a silicon nitride oxide film (SiOxNy) may be used by a known means (a sputtering method, an LPCVD method, a plasma CVD method, or the like). Of course, the base film is not limited to a single layer but may be a stacked layer.

Next, a semiconductor film 213 is formed on the base film. As the semiconductor film 213, a semiconductor film having an amorphous structure is formed with a thickness of 25 to 80 nm (preferably 30 to 60 nm) by a known means (a sputtering method, an LPCVD method, a plasma CVD method, or the like). Although there is no limitation on the material of the semiconductor film, it is preferable to use silicon or a silicon germanium (SiGe) alloy. Subsequently, the crystalline semiconductor film obtained by performing a known crystallization treatment (eg, a laser crystallization method, a thermal crystallization method, or a thermal crystallization method using a catalyst such as nickel) is patterned into a desired shape.

An insulating film 214 is formed on the patterned semiconductor film 215 from a silicon oxide film or a silicon nitride oxide film (SiOx
An insulating film containing silicon such as Ny) is formed, and then a conductive film 216 is formed. Although there is no particular limitation on the material of the conductive film, the conductive film may be formed using an element selected from Ta, W, Ti, Mo, Cu, Cr, and Nd, or an alloy material or a compound material containing the element as a main component. . Alternatively, a semiconductor film typified by a crystalline silicon film doped with an impurity element such as phosphorus may be used. Further, an AgPdCu alloy may be used. Of course, the conductive film may be a stacked layer instead of a single layer. Subsequently, etching is performed to form a gate electrode 2 having a tapered end.
17 is formed.

Then, a doping process is performed to introduce an impurity element. In the doping treatment, an impurity element imparting N-type or P-type is introduced by an ion doping method, an ion implantation method, or the like. By the doping process, a region 218 into which the impurity element is introduced at a high concentration, a region 219 which is tapered at the end of the gate electrode and is introduced at a low concentration, and a region (channel region) 220 into which the impurity is not introduced are formed.

Thereafter, the recovery of the crystallinity of the semiconductor layer and the activation of the dopant added to the semiconductor layer are performed by the laser annealing method described in the first half of the embodiment of the invention.
As the laser, for example, the second harmonic of a YAG laser is used, and a suitable optical system, for example, the optical system shown in FIG. Thereafter, the TFT is completed by, for example, a known method. Alternatively, the TFT may be manufactured by a method devised by the practitioner. In a later example, an example of a TFT manufacturing process will be described.

[0038]

[Embodiment 1] In this embodiment, another example of a laser beam irradiation method will be described. At the time of laser beam irradiation, if the substrate to be irradiated has insufficient flatness, it is difficult to control the focus position of the laser beam and the position of the substrate. In this embodiment, an example of a method for performing laser beam irradiation while sufficiently maintaining the flatness of a substrate will be described. In the present embodiment, an example is shown in which the substrate is scanned while air is levitated above a very flat plate, and laser annealing is performed on the entire surface of the substrate.

This embodiment will be described with reference to FIG. The stage 221 is provided with a plurality of air outlets 222, and the substrate 224 is caused to float by the force of the air injected from the outlets 222. The air used is
It suffices that the semiconductor elements such as nitrogen and air have no adverse effect. The air is supplied from a cylinder 225.
A gap for introducing the linear beam 223 is provided on the stage 221, and the linear beam 223 is irradiated on the substrate 224 through the gap. The laser annealing is performed on the entire surface of the substrate 224 by moving the substrate in a direction parallel to the stage 221 while irradiating the substrate 224 with the linear beam 223.
There are various methods for moving the substrate, but since the substrate is in a state of air floating, by means not shown,
The pressing may be performed by pressing the edge of the substrate or by gripping and pulling the edge of the substrate.

As a laser oscillator to be used, for example, a power light 9030 manufactured by Continum is converted into a second harmonic by using an SHG crystal and used. This laser oscillator has the ability to emit 800 mJ of energy per pulse.
Up to 30 pulses can be emitted per second. The beam spot is a circle having a diameter of 9 mm. The laser beam emitted from this laser oscillator is converted into a linear beam by the optical system shown in FIG. 2, for example, and is used in this embodiment.
Since the coherent length d of the YAG laser is usually about 10 mm, the coherence can be suppressed by setting the step of the stepped glass plate 202 to be d / (n-1). Since the refractive index of the glass plate is about 1.5 with respect to the wavelength of the second harmonic of the YAG laser, it is understood that the step should be set to 20 mm.

The cylindrical lens array 203 is formed by using, for example, three cylindrical lenses having a focal length of 30 mm and a width of 3 mm. From this, the number of steps of the glass plate 202 processed in a stepped manner may be two. The laser beam that does not pass through the glass plate 202 processed in a step shape is
The optical system is arranged so as to be incident on the outermost cylindrical lens of the cylindrical lens array 203. The laser beam passing through each step of the glass plate 202 processed in a step shape is incident on each of the cylindrical lenses forming the cylindrical lens array.

The laser beam emitted from the cylindrical lens array 203 enters the cylindrical lens 204, and is combined into one on the irradiation surface. At this time, the focal length of the cylindrical lens 204 is set to 1500
mm, the length of the resulting linear beam is 150 mm. In this state, a sufficient energy density cannot be obtained on the irradiation surface, so that the cylindrical lens 206 forms a thinner linear beam to increase the energy density. In order to suppress the influence of interference, the focal length of the cylindrical lens 206 is preferably 400 mm or more. As a result, a linear beam having a relatively uniform energy distribution with little influence of interference is obtained. In order to avoid interference with the light reflected on the back surface of the glass substrate, the linear beam is made incident from an oblique direction on the glass substrate. This angle may be appropriately determined by a practitioner, but a suitable value is approximately 10 ° as a guide. The light transmitted through the glass substrate is again irradiated on the glass substrate by a reflection mirror, and is used for annealing the source region and the drain region. The laser beam turned back by the reflection mirror is reflected at a slight angle so as not to return to the laser oscillator. Great care must be taken because returning the laser beam to the oscillator can damage the rod of the solid state laser.

The energy density of the linear beam may be appropriately determined by a practitioner. If the object to be irradiated is a semiconductor film having a thickness of about 50 nm, about 50 to 250 mJ / cm 2 may be used as a guide.

[Embodiment 2] In this embodiment, another example of a laser beam irradiation method will be described. In the case of the present invention, the laser beam irradiated from the back side of the substrate is focused on the back side of the substrate. Therefore, when the laser beam transmitted through the substrate is again irradiated from the front side of the substrate by a mirror or the like, the laser beam is focused. The position may not be appropriate. In such a case, the laser beam may be condensed again using a concave mirror or the like as a mirror to secure a sufficient energy density on the surface of the substrate.

This embodiment will be described with reference to FIG. In the figure,
4 are the same as those in FIG. The linear beam 223 that has passed through the substrate 224 is reflected by the cylindrical concave mirror 227 and is again irradiated on the substrate 224. At this time, the height of the condensing position of the linear beam formed by the cylindrical concave mirror 227 may be the same as the height of the condensing position of the linear beam formed by the linear beam 223. As a result, the linear beam emitted from the back side and the linear beam emitted from the front side of the glass substrate have substantially the same short axis width (in this specification, the short side when the linear beam is viewed as a rectangle). .)).

If the width of the short axis of the linear beam is too small, the productivity is poor, and if it is too large, the energy density cannot be secured. Therefore, it must be carefully adjusted. Therefore, it is important that the short-axis width of the linear beam emitted from the back side of the glass substrate and the short-axis width of the linear beam emitted from the front side of the glass substrate be the same. Example 1
Assuming that the laser oscillator described above is used, the short-axis width of an appropriate linear beam is about 50 to 1000 μm. 5
If a short axis width of 0 μm or less is secured, a very special optical system and a laser oscillator with high beam quality are required, which makes it difficult to configure the apparatus. 1000 μm
If the above short axis width is secured, the output of the laser oscillator is likely to be insufficient. Alternatively, a very short linear beam is formed to secure the energy density. In this case, the productivity is low and the significance of forming a linear beam is reduced.

The energy density of the linear beam may be appropriately determined by a practitioner. Since a concave mirror is used for the reflector, the required energy density is slightly smaller than that shown in the first embodiment. If the object to be irradiated is a semiconductor film having a thickness of about 50 nm, the target may be about 50 to 200 mJ / cm ² .

[Embodiment 3] In this embodiment, an example in which the substrate is heated in the laser beam irradiation method of the present invention will be described. In the case of the present invention, it is preferable to use a linear beam because of high productivity. Also, since the length of the linear beam is closely related to productivity, it is important to obtain a linear beam as long as possible. However, since the linear beam cannot be made longer than the capability of the laser oscillator, in this embodiment,
A method of obtaining a longer linear beam by adding another energy that supplements the energy of the laser beam will be described.

This embodiment will be described with reference to FIG. In the figure,
4 are the same as those in FIG. The linear beam 223 transmitted through the substrate 224 is reflected by the reflector 226.
And is again irradiated on the substrate 224. Further, when the substrate is heated by the lamp 230, shortage of energy of the laser beam can be compensated. Lamp 23
For 0, a halogen lamp, a metal halide lamp, a high-pressure mercury lamp, a high-pressure sodium lamp, a xenon lamp, or the like may be used. Since the light of the lamp is generally emitted in all directions, it is preferable to use the lamp umbrella 229 to restrict the direction of the light and increase the light use efficiency.

The irradiation position of the lamp 230 on the glass substrate 224 may be around the irradiation position of the linear beam. Generally, the strain point temperature of the glass substrate is about 600 ° C., so it is safe to set the maximum temperature of the glass substrate 224 by the lamp to about 600 ° C. or less. However, since the irradiation time of the lamp at an arbitrary point on the glass substrate 224 is short, the lamp may be used at a temperature exceeding the strain point temperature in some cases. The practitioner needs to determine the optimum combination in consideration of both the productivity and the durability of the glass substrate.

The energy density of the linear beam may be appropriately determined by a practitioner. Since a lamp is used, the required energy density is slightly smaller than that shown in the first embodiment. If the object to be irradiated is a semiconductor film having a thickness of about 50 nm, the target may be about 50 to 200 mJ / cm ² .

[Embodiment 4] In this embodiment, another example of a laser beam irradiation method will be described. As described above, it is very important to consider a countermeasure for return light in a laser device. When the laser beam transmitted through the glass substrate is reflected by the reflector and irradiated on the glass substrate again, if the laser beam is returned to exactly the same place, it is highly possible that the laser beam returns to the laser oscillator. Therefore, in all of the above-described inventions, the position of the laser beam irradiated from the front side and the position of the laser beam irradiated from the back side must be shifted. However, by devising the form of the reflector, it is possible to bring about a problem of return light without any problem.

This embodiment will be described with reference to FIG. In the figure,
4 are the same as those in FIG. The linear beam 223 transmitted through the substrate 224 is reflected by the reflector 231.
And 232, and is again irradiated on the substrate 224. When the two reflectors are properly arranged, the glass substrate 2
The direction of the linear beam incident on the front surface of the glass substrate 224 and the direction of the linear beam incident on the back surface of the glass substrate 224 can be different from each other. Therefore, there is no need to worry that the reflected light from the reflector returns to the laser oscillator.

One side of the reflectors 231 and 232 may be a concave mirror, and the energy density on the irradiation surface may be increased by condensing the laser beam. Further, in order to reduce the laser energy required for annealing the semiconductor film, it may be combined with a lamp. Further, instead of the linear beam 223 incident on the back side of the glass substrate, only a lamp may be used.

This embodiment can be used in combination with any of the other embodiments.

Embodiment 5 In this embodiment, a method for manufacturing an active matrix substrate will be described with reference to FIGS. In this specification, a substrate in which a CMOS circuit, a driver circuit, a pixel portion having a pixel TFT, and a storage capacitor are formed on the same substrate is referred to as an active matrix substrate for convenience.

First, in this embodiment, Corning # 70
A substrate 300 made of glass such as barium borosilicate glass represented by 59 glass or # 1737 glass, or aluminoborosilicate glass is used. Note that a quartz substrate may be used as the substrate 300. Further, a plastic substrate which has heat resistance enough to withstand the processing temperature of this embodiment and has a light-transmitting property with respect to the laser used in this embodiment may be used.

Next, a base film 301 made of an insulating film such as a silicon oxide film, a silicon nitride film, or a silicon oxynitride film is formed on the substrate 300. Although a two-layer structure is used as the base film 301 in this embodiment, a single-layer film of the insulating film or a structure in which two or more layers are stacked may be used. As the first layer of the base film 301, SiH ₄ , N 2
The silicon oxynitride film 301a formed by using H ₃ and N ₂ O as a reaction gas is formed to a thickness of 10 to 200 nm (preferably 50 to 10 nm).
0 nm). In this embodiment, a 50 nm-thick silicon oxynitride film 301a (composition ratio: Si = 32%, O = 27%,
N = 24%, H = 17%). Next, as a second layer of the base film 301, a plasma CVD
A silicon oxynitride film 301b formed by using iH ₄ and N ₂ O as a reaction gas has a thickness of 50 to 200 nm (preferably 100 nm).
(About 150 nm). In this embodiment, a 100-nm-thick silicon oxynitride film 301b (composition ratio Si =
32%, O = 59%, N = 7%, H = 2%).

Next, the semiconductor layers 402 to 406 shown in FIG. 8B are formed on the base film. Semiconductor layers 402 to 40
Reference numeral 6 denotes a method of forming a semiconductor film with a thickness of 25 to 80 nm (preferably 30 to 60 nm) by a known means (sputtering method, LPCVD method, plasma CVD method, or the like), and a known crystallization method (laser crystallization method). , A thermal crystallization method using an RTA or a furnace annealing furnace, a thermal crystallization method using a metal element that promotes crystallization, or the like). Examples of the semiconductor film include an amorphous semiconductor film, a microcrystalline semiconductor film, and a crystalline semiconductor film. A compound semiconductor film having an amorphous structure such as an amorphous silicon germanium film may be used. In this embodiment, an amorphous silicon film 302 having a thickness of 55 nm is formed by a plasma CVD method. Then, for example, a solution containing nickel is held on the amorphous silicon film so that the metal-containing layer 30 is formed.
3 and dehydrogenation (500 ° C.,
1 hour), and then heat crystallization (550 ° C., 4 hours)
To form a crystalline silicon film.

Subsequently, a resist mask is formed directly on the semiconductor layers 402 to 406 by photolithography, and an element belonging to Group 15 or a rare gas or an element belonging to Group 15 and An impurity region is formed by adding an element belonging to group III. The doping treatment may be performed by an ion doping method or an ion implantation method. The condition of the ion doping method is that the dose is 5 × 10 ¹³ / cm ²
As described above, the acceleration voltage is set to 10 to 100 keV. In this embodiment, the dose is set to 5 × 10 ¹⁵ / cm ² and the acceleration voltage is set to 30 keV. Here, Ar is used as an element belonging to the rare gas.

Next, heat treatment for gettering the metal element used to promote crystallization to the impurity region is performed. The heat treatment is performed by a thermal annealing method using a furnace annealing furnace. The thermal annealing is performed at 400 ° C. or more in a nitrogen atmosphere having an oxygen concentration of 1 ppm or less, preferably 0.1 ppm or less. In this embodiment, 55
Heat treatment was performed at 0 ° C. for 4 hours. Thus, the nickel content of the gettering region can be significantly reduced.

The resist is removed, and the impurity region of the crystalline semiconductor film after the gettering is removed to remove the semiconductor layer 40.
2 to 406 are formed.

When a crystalline semiconductor film is formed by a laser crystallization method, a pulse oscillation type or continuous emission type excimer laser, YAG laser, YVO ₄ laser, YLF
A laser, a YAlO ₃ laser, a glass laser, a ruby laser, a Ti: sapphire laser, or the like can be used.
In the case of using these lasers, a method in which a laser beam emitted from a laser oscillator is linearly condensed by an optical system and irradiated to a semiconductor film is preferably used. The crystallization conditions are appropriately selected by the practitioner. When an excimer laser is used, the pulse oscillation frequency is set to 300 Hz, and the laser energy density is set to 100 to 700 mJ / cm ² (typically 200 to 700 mJ / cm ² ).
300 mJ / cm ² ). When a YAG laser is used, its second harmonic is used to generate a pulse oscillation frequency of 30 to 3.
000 Hz and laser energy density of 300 to 10
MJ / cm ² may (typically 350~500mJ / cm ²⁾ to. And a width of 50 to 1000 μm, for example 400 μm
Irradiates the laser light condensed linearly over the entire surface of the substrate,
At this time, the overlapping ratio (overlap ratio) of the linear beams may be set to 50 to 98%.

After the formation of the semiconductor layers 402 to 406, a slight amount of impurity element (boron or phosphorus) may be doped in order to control the threshold value of the TFT.

Next, a gate insulating film 407 covering the semiconductor layers 402 to 406 is formed. The gate insulating film 407 is formed by a plasma CVD method or a sputtering method and has a thickness of 40 to
The insulating film containing silicon is formed to have a thickness of 150 nm. In this embodiment, a silicon oxynitride film (composition ratio: Si = 32%, O = 59%, N =
7%, H = 2%). Needless to say, the gate insulating film is not limited to the silicon oxynitride film, and another insulating film containing silicon may be used as a single layer or a stacked structure.

When a silicon oxide film is used, TEOS (Tetraethyl Orthosilicate) is formed by a plasma CVD method.
And O ₂ , a reaction pressure of 40 Pa and a substrate temperature of 300 to
400 ° C., high frequency (13.56 MHz) power density 0.
It can be formed by discharging at 5 to 0.8 W / cm ² .
The silicon oxide film thus manufactured is thereafter
Good characteristics as a gate insulating film can be obtained by thermal annealing at up to 500 ° C.

Next, as shown in FIG. 8B, a first conductive film 408 having a thickness of 20 to 100 nm and a second conductive film 40 having a thickness of 100 to 400 nm are formed on the gate insulating film 407.
9 are laminated. In this embodiment, a 30 nm-thick T
a first conductive film 408 made of an aN film and a film thickness of 370 nm
A second conductive film 409 made of a W film was laminated. T
The aN film was formed by a sputtering method, and was sputtered using a Ta target in an atmosphere containing nitrogen. The W film was formed by a sputtering method using a W target. In addition, thermal CV using tungsten hexafluoride (WF ₆ )
It can also be formed by Method D. In any case, it is necessary to lower the resistance in order to use it as a gate electrode,
It is desirable that the resistivity of the W film be 20 μΩcm or less. The resistivity of the W film can be reduced by enlarging the crystal grains. However, when the W film contains many impurity elements such as oxygen, the crystallization is inhibited and the resistance is increased. Therefore, in this embodiment, the W film is formed by a sputtering method using a high-purity W (purity of 99.9999%) target, and further taking care not to mix impurities from the gas phase during film formation. By forming, a resistivity of 9 to 20 μΩcm could be realized.

In this embodiment, the first conductive film 408
Is TaN and the second conductive film 409 is W, but there is no particular limitation, and any of Ta, W, Ti, Mo, Al, Cu,
It may be formed of an element selected from Cr and Nd, or an alloy material or a compound material containing the element as a main component.
Alternatively, a semiconductor film typified by a crystalline silicon film doped with an impurity element such as phosphorus may be used. AgP
A dCu alloy may be used. A first conductive film formed of a tantalum (Ta) film, a second conductive film formed of a W film, a first conductive film formed of a titanium nitride (TiN) film, and a second conductive film formed of a titanium nitride (TiN) film; Are combined with a W film, the first conductive film is formed of a tantalum nitride (TaN) film, and the second conductive film is formed of an Al film, and the first conductive film is formed of a tantalum nitride (TaN) film. Alternatively, a combination of the second conductive film and the Cu film may be used. A first conductive film is formed of a tantalum nitride (TaN) film, a second conductive film is formed of an Al film,
Further, a Ti film may be combined as the third conductive film.

Next, resist masks 410 to 415 are formed by photolithography, and a first etching process for forming electrodes and wirings is performed.
The first etching process is performed under the first and second etching conditions. In this embodiment, as the first etching condition, an ICP (Inductively Coupled Plasma) etching method is used, and C is used as an etching gas.
Using F ₄ , Cl ₂ and O ₂ , each gas flow ratio was 2
At 5/25/10 (sccm), 500 W RF (13.56 MHz) power was applied to the coil-type electrode at a pressure of 1 Pa to generate plasma and perform etching. Here, a dry etching apparatus (Model E645- □ ICP) using ICP manufactured by Matsushita Electric Industrial Co., Ltd. was used. A 150 W RF (13.56 MHz) power is also applied to the substrate side (sample stage), and a substantially negative self-bias voltage is applied.
The W film is etched under the first etching conditions to make the end of the first conductive layer tapered.

Then, a mask 410 made of resist is formed.
The second etching condition was changed without removing 415, CF ₄ and Cl ₂ were used as etching gases, the respective gas flow ratios were 30/30 (sccm), and the pressure was 1 Pa to form a coil-type electrode. RF (13.56 MHz) power of 500 W was applied to generate plasma, and etching was performed for about 30 seconds. The substrate side (sample stage) also has a 20 W RF (13.56
MHz) power is applied and a substantially negative self-bias voltage is applied. Under the second etching condition in which CF ₄ and Cl ₂ are mixed, the W film and the TaN film are etched to the same extent. Note that in order to perform etching without leaving a residue on the gate insulating film, the etching time is preferably increased by about 10 to 20%.

In the first etching process, the shape of the mask made of resist is made appropriate so that
The ends of the first conductive layer and the second conductive layer are tapered due to the effect of the bias voltage applied to the substrate side. The angle of the tapered portion is 15 to 45 °. In this manner, the first shape conductive layers 417 to 422 (the first conductive layers 417a to 422a and the second conductive layers 417b to 417b) formed of the first conductive layer and the second conductive layer by the first etching process.
2b) is formed. 416 is a gate insulating film,
The region not covered by the conductive layers 417 to 422 having the
A region that is etched and thinned by about 50 nm is formed.

Then, a first doping process is performed without removing the resist mask to add an impurity element imparting n-type to the semiconductor layer. (FIG. 9A) The doping treatment may be performed by an ion doping method or an ion implantation method. The condition of the ion doping method is that the dose amount is 1 × 10
^{13 to} 5 × 10 ¹⁵ / cm ² and an acceleration voltage of 60 to 100
Performed as keV. In this embodiment, the dose amount is 1.5 ×
The test was performed at 10 ¹⁵ / cm ² and an acceleration voltage of 80 keV. As the impurity element imparting n-type, an element belonging to Group 15 of the periodic table, typically phosphorus (P) or arsenic (As) is used. Here, phosphorus (P) is used. In this case, the conductive layer 4
Reference numerals 17 to 421 serve as masks for the impurity element imparting n-type, and the first high-concentration impurity regions 306 are self-aligned.
To 310 are formed. First high concentration impurity region 306
To 310, an impurity element imparting n-type is added in a concentration range of 1 × 10 ²⁰ to 1 × 10 ²¹ / cm ³ .

Next, a second etching process is performed without removing the resist mask. Here, the W film is selectively etched using CF ₄ , Cl ₂ and O _{2 as} an etching gas. At this time, second conductive layers 428b to 433b are formed by a second etching process. on the other hand,
The first conductive layers 417a to 422a are hardly etched to form second shape conductive layers 428 to 433.

Next, a second doping process is performed as shown in FIG. 9B without removing the resist mask. In this case, the dose is lower than that of the first doping process, and at a high acceleration voltage of 70 to 120 keV,
An impurity element imparting n-type is introduced. In this embodiment, the dose is 1.5 × 10 ¹⁴ / cm ² and the acceleration voltage is 90
It was performed as keV. In the second doping process, the second shape conductive layers 428 to 433 are used as masks and the second doping process is performed.
The impurity element is also introduced into the semiconductor layer below the conductive layers 428b to 433b, and the second high concentration impurity regions 423a to 427a and the low concentration impurity regions 423b are newly added.
To 427b are formed.

Next, after removing the mask made of resist, masks 434a and 434a made of resist are newly added.
34b is formed, and a third etching process is performed as shown in FIG. SF ₆ and Cl ₂ were used as etching gases, and the gas flow ratio was 50/10 (scc
m) and a pressure of 1.3 Pa and 500
An RF (13.56 MHz) power of W is applied to generate plasma, and an etching process is performed for about 30 seconds. 10 W RF (13.56 MH) on the substrate side (data stage)
z) Turn on the power and apply a substantially non-self bias voltage. Thus, the p-channel type TFT and the TFT (pixel T
The TaN film (FT) is etched to form third shape conductive layers 435 to 438.

Then, after removing the resist mask, the gate insulating film 416 is selectively removed using the second shape conductive layers 428 and 430 and the second shape conductive layers 435 to 438 as masks. Insulating layers 439-44
4 is formed. (FIG. 10A)

Next, a mask 4 made of a new resist
45a to 445c are formed and a third doping process is performed. By the third doping treatment, the impurity region 4 in which the impurity element imparting the conductivity type opposite to the one conductivity type is added to the semiconductor layer serving as the active layer of the p-channel TFT.
46 and 447 are formed. Second conductive layers 435a, 43
8a is used as a mask for the impurity element, and an impurity element imparting p-type is added to form an impurity region in a self-aligned manner. In this embodiment, the impurity regions 446 and 447 are formed by an ion doping method using diborane (B ₂ H ₆ ). (FIG. 10B) In this third doping process, the semiconductor layers forming the n-channel TFT are covered with masks 445a to 445c made of resist. Phosphorus is added at different concentrations to the impurity regions 446 and 447 by the first doping process and the second doping process, and the concentration of the impurity element imparting p-type is set to 2 × in each of the regions. 10 ^{20 to} 2 ×
By performing the doping treatment to have a density of 10 ²¹ / cm ³ , no problem arises because the p-type TFT functions as a source region and a drain region. In this embodiment, since a part of the semiconductor layer serving as the active layer of the p-channel TFT is exposed, there is an advantage that an impurity element (boron) can be easily added.

Through the above steps, impurity regions are formed in the respective semiconductor layers.

Next, a mask 445a made of resist is used.
To 445c are removed to form a first interlayer insulating film 461. As the first interlayer insulating film 461, plasma C
Using a VD method or a sputtering method, a thickness of 100 to 200
The insulating film containing silicon is formed as nm. In this embodiment, a silicon oxynitride film with a thickness of 150 nm is formed by a plasma CVD method. Of course, the first interlayer insulating film 461
Is not limited to a silicon oxynitride film, and another insulating film containing silicon may be used as a single layer or a stacked structure.

Next, as shown in FIG. 10C, the processing by the laser disclosed in the present invention is performed. As a result, the crystallinity of the semiconductor layer is restored, and the impurity element added to each semiconductor layer is activated. Further, if there is a light source that can replace the laser, it may be used. The procedure of this step is shown below. Laser irradiation is performed from the rear surface side of the substrate 300, and the impurity regions 446 and 447 are laser-annealed. At this time, the laser beam transmitted through the substrate 300 is reflected by the reflection mirror 106, and is again irradiated on the impurity regions 446a, 446b, 447a, and 447b from the front side of the substrate 300. As a result, without increasing the laser energy incident on the impurity regions 446c, 446d, 447c, and 447d, the impurity regions 44
The laser energy incident on 6a, 446b, 447a, 447b can be increased. In order to perform uniform laser annealing on the entire surface of the substrate 300, for example, the linear beam described in the embodiment may be used. Alternatively, a laser of a point light source may be scanned by a galvanometer or the like to irradiate the entire surface of the substrate with a laser beam.

Further, a heat treatment is performed at 300 to 550 ° C. for 1 to 12 hours in an atmosphere containing 3 to 100% of hydrogen to hydrogenate the semiconductor layer. In this embodiment, heat treatment was performed at 410 ° C. for one hour in a nitrogen atmosphere containing about 3% of hydrogen. In this step, dangling bonds in the semiconductor layer are terminated by hydrogen contained in the interlayer insulating film. As another means of hydrogenation, plasma hydrogenation (using hydrogen excited by plasma) may be performed.

Next, a second interlayer insulating film 462 made of an inorganic insulating material or an organic insulating material is formed on the first interlayer insulating film 461. In this embodiment, the film thickness is 1.6 μm
Was formed, but the viscosity was 10 to 1000
cp, preferably 40 to 200 cp, and those having irregularities on the surface were used.

In the present embodiment, in order to prevent specular reflection, irregularities are formed on the surface of the pixel electrode by forming a second interlayer insulating film having irregularities on the surface. In addition, a projection may be formed in a region below the pixel electrode in order to obtain light scattering by providing unevenness on the surface of the pixel electrode. In that case, the projection can be formed using the same photomask as that for forming the TFT, so that the projection can be formed without increasing the number of steps. Note that the protrusions may be appropriately provided on the substrate in the pixel portion region other than the wiring and the TFT portion. Thus, irregularities are formed on the surface of the pixel electrode along irregularities formed on the surface of the insulating film covering the convex portions.

As the second interlayer insulating film 462, a film whose surface is flattened may be used. In that case, after forming the pixel electrode, the surface is made uneven by adding a process such as a known sand blasting method or an etching method to prevent specular reflection and increase whiteness by scattering reflected light. Is preferred.

Then, in drive circuit 506, wirings 463 to 467 electrically connected to the respective impurity regions, respectively.
To form Note that these wirings are made of a 50 nm thick T
A laminated film of an i film and a 500 nm-thick alloy film (an alloy film of Al and Ti) is formed by patterning.

In the pixel portion 507, a pixel electrode 470, a gate wiring 469, and a connection electrode 468 are formed. (FIG. 11) With the connection electrode 468, the source wiring (the lamination of 443b and 449) is electrically connected to the pixel TFT. The gate wiring 469 is connected to the pixel T
An electrical connection is formed with the gate electrode of the FT. Also,
The pixel electrode 470 is electrically connected to the drain region 442 of the pixel TFT, and is also electrically connected to the semiconductor layer 458 functioning as one electrode forming a storage capacitor. In addition, as the pixel electrode 470, a material having excellent reflectivity, such as a film containing Al or Ag as a main component or a stacked film thereof, is preferably used.

As described above, the n-channel TFT 50
1 and a CMOS circuit comprising a p-channel TFT 502;
And driving circuit 506 having n-channel TFT 503
And a pixel portion 507 having a pixel TFT 504 and a storage capacitor 505 can be formed over the same substrate. Thus, an active matrix substrate is completed.

The n-channel TFT 50 of the driving circuit 506
Reference numeral 1 denotes a low-concentration impurity region 42 overlapping the channel region 423c and the first conductive layer 428a forming a part of the gate electrode.
3b (GOLD region) and a high-concentration impurity region 423a functioning as a source region or a drain region. A p-channel TFT 502 connected to the n-channel TFT 501 via an electrode 466 to form a CMOS circuit
Include a channel region 446d, impurity regions 446b and 446c formed outside the gate electrode, and a high-concentration impurity region 446a functioning as a source region or a drain region.
have. The n-channel TFT 503 includes a channel region 425c and a first region forming a part of a gate electrode.
Low concentration impurity region 425b overlapping with conductive layer 430a of
(GOLD region) and a high-concentration impurity region 425a functioning as a source region or a drain region.

The pixel TFT 504 in the pixel portion has a channel region 426c, a low concentration impurity region 426b (LDD region) formed outside the gate electrode, and a high concentration impurity region 426a functioning as a source region or a drain region. . The semiconductor layers 447a and 447b functioning as one electrode of the storage capacitor 505 are each doped with an impurity element imparting p-type. Storage capacity 50
5 is formed with electrodes (lamination of 438a and 438b) and semiconductor layers 447a to 447c using the insulating film 444 as a dielectric.

Further, in the pixel structure of this embodiment, the end of the pixel electrode is arranged so as to overlap with the source wiring so that the gap between the pixel electrodes is shielded from light without using a black matrix.

FIG. 12 is a top view of a pixel portion of an active matrix substrate manufactured in this embodiment. Note that the same reference numerals are used for portions corresponding to FIGS.
A chain line AA ′ in FIG. 11 corresponds to a cross-sectional view cut along a chain line AA ′ in FIG. The chain line B in FIG.
-B 'corresponds to a cross-sectional view taken along a chain line BB' in FIG.

[Embodiment 6] In this embodiment, a process for fabricating a reflection type liquid crystal display device from the active matrix substrate produced in Embodiment 5 will be described below. FIG. 13 is used for the description.

First, according to the fifth embodiment, after obtaining the active matrix substrate in the state shown in FIG. 11, an alignment film 567 is formed on at least the pixel electrode 470 on the active matrix substrate shown in FIG. Note that in this embodiment, before forming the alignment film 567, a columnar spacer 572 for maintaining a substrate interval was formed at a desired position by patterning an organic resin film such as an acrylic resin film. Instead of the columnar spacers, spherical spacers may be spread over the entire surface of the substrate.

Next, a counter substrate 569 is prepared. Next, the coloring layers 570 and 571 and the planarizing film 573 are formed over the counter substrate 569. The red coloring layer 570 and the blue coloring layer 572 are overlapped to form a light shielding portion. Alternatively, the light-blocking portion may be formed by partially overlapping the red coloring layer and the green coloring layer.

In this embodiment, the substrate shown in the fifth embodiment is used. Therefore, FIG. 1 shows a top view of the pixel portion of the fifth embodiment.
2, at least the gate wiring 469 and the pixel electrode 470
, The gap between the gate wiring 469 and the connection electrode 468, and the gap between the connection electrode 468 and the pixel electrode 470 need to be shielded from light. In this embodiment, the colored layers are arranged such that the light-shielding portion formed of the colored layers is overlapped at the positions where the light is to be shielded, and the opposing substrates are bonded to each other.

As described above, the number of steps can be reduced by shielding the gap between each pixel with the light-shielding portion composed of the colored layers without forming a light-shielding layer such as a black mask.

Next, a counter electrode 576 made of a transparent conductive film was formed on at least the pixel portion on the flattening film 573, an alignment film 574 was formed on the entire surface of the counter substrate, and rubbing treatment was performed.

Then, the active matrix substrate on which the pixel portion and the driving circuit are formed and the opposing substrate are sealed with a sealing material 568.
Paste in. A filler is mixed in the sealant 568, and the two substrates are bonded to each other at a uniform interval by the filler and the columnar spacer. afterwards,
A liquid crystal material 575 is injected between the two substrates, and completely sealed with a sealant (not shown). A known liquid crystal material may be used for the liquid crystal material 575. Thus, the reflection type liquid crystal display device shown in FIG. 13 is completed. Then, if necessary, the active matrix substrate or the opposing substrate is cut into a desired shape. Further, a polarizing plate (not shown) was attached only to the counter substrate. Then, using a known technique, F
PC was pasted.

The liquid crystal display panel manufactured as described above can be used as a display section of various electronic devices.

This embodiment can be freely combined with any one of the first to fifth embodiments.

[Embodiment 7] In this embodiment, an example in which a light emitting device is manufactured will be described. In this specification, a light-emitting device refers to a display panel in which a light-emitting element formed over a substrate is sealed between the substrate and a cover material, and a light-emitting element formed on the display panel.
This is a generic term for display modules on which C is mounted.
Note that the light-emitting element has a layer (light-emitting layer) containing an organic compound capable of obtaining luminescence (Electro Luminescence) generated by applying an electric field, an anode layer, and a cathode layer.
In addition, luminescence in an organic compound includes light emission (fluorescence) when returning from a singlet excited state to a ground state and light emission (phosphorescence) when returning from a triplet excited state to a ground state. Alternatively, both light emissions are included.

FIG. 14 is a sectional view of the light emitting device of this embodiment. 14, the switching TFT 603 provided on the substrate 700 is the n-channel TFT 50 of FIG.
3 is formed. Therefore, for the description of the structure, the description of the n-channel TFT 503 may be referred to.

Although the present embodiment has a double gate structure in which two channel regions are formed, a single gate structure in which one channel region is formed or a triple gate structure in which three channel regions are formed may be used.

The drive circuit provided on the substrate 700 is shown in FIG.
It is formed using one CMOS circuit. Therefore, the description of the structure is made of the n-channel TFT 501 and the p-channel TFT
Reference may be made to the description of 502. In this embodiment, a single gate structure is used, but a double gate structure or a triple gate structure may be used.

The wirings 701 and 703 function as a source wiring of a CMOS circuit, and the wiring 702 functions as a drain wiring.
The wiring 704 is connected to the source wiring 708 and the switching T
The wiring 705 functions as a wiring for electrically connecting the source region of the FT to the source region.
It functions as a wiring for electrically connecting the drain region of the FT.

The current control TFT 604 corresponds to p
It is formed using a channel type TFT 502. Therefore,
For the description of the structure, the description of the p-channel TFT 502 can be referred to. In this embodiment, a single gate structure is used, but a double gate structure or a triple gate structure may be used.

A wiring 706 is a source wiring (corresponding to a current supply line) of the current control TFT, and 707 is an electrode which is electrically connected to the pixel electrode 710 by being superposed on the pixel electrode 710 of the current control TFT. is there.

Reference numeral 710 denotes a pixel electrode (anode of a light emitting element) made of a transparent conductive film. As a transparent conductive film,
A compound of indium oxide and tin oxide, a compound of indium oxide and zinc oxide, zinc oxide, tin oxide, or indium oxide can be used. Further, a material obtained by adding gallium to the transparent conductive film may be used. The pixel electrode 710 has a flat interlayer insulating film 7 before forming the wiring.
11 is formed. In this embodiment, it is very important to flatten the steps due to the TFT using the flattening film 711 made of resin. Since a light-emitting layer formed later is extremely thin, poor light emission may be caused by the presence of a step. Therefore, it is desirable to planarize the pixel electrode before forming it so that the light emitting layer can be formed as flat as possible.

After forming the wirings 701 to 707, a bank 712 is formed as shown in FIG. Bank 712 is 10
The insulating film or the organic resin film containing silicon having a thickness of 0 to 400 nm may be formed by patterning.

Since the bank 712 is an insulating film,
Attention must be paid to electrostatic breakdown of the element during film formation.
In this embodiment, carbon particles or metal particles are added to the insulating film that is a material of the bank 712 to lower the resistivity and suppress generation of static electricity. At this time, the resistivity is 1 × 10 ⁶ to 1 × 1.
The addition amount of the carbon particles and the metal particles may be adjusted so as to be 0 ¹² Ωm (preferably 1 × 10 ⁸ to 1 × 10 ¹⁰ Ωm).

A light emitting layer 713 is formed on the pixel electrode 710. Although only one pixel is shown in FIG. 14, in this embodiment, light emitting layers corresponding to each of R (red), G (green), and B (blue) are separately formed. In this embodiment, the low molecular weight organic light emitting material is formed by a vapor deposition method.
Specifically, a copper phthalocyanine (CuPc) film having a thickness of 20 nm is provided as a hole injection layer, and a light emitting layer is formed on the copper phthalocyanine film.
It has a laminated structure in which a 0 nm thick tris-8-quinolinolato aluminum complex (Alq ₃ ) film is provided. The emission color can be controlled by adding a fluorescent dye such as quinacridone, perylene or DCM1 to Alq ₃ .

However, the above example is an example of the organic light emitting material that can be used as the light emitting layer, and it is not necessary to limit the present invention to this. A light-emitting layer (a layer for performing light emission and carrier movement therefor) may be formed by freely combining a light-emitting layer, a charge transport layer, or a charge injection layer. For example, in this embodiment, an example in which a low molecular weight organic light emitting material is used as the light emitting layer has been described, but a high molecular weight organic light emitting material may be used. It is also possible to use an inorganic material such as silicon carbide for the charge transport layer and the charge injection layer. Known materials can be used for these organic light emitting materials and inorganic materials.

Next, a cathode 714 made of a conductive film is provided on the light emitting layer 713. In this embodiment, an alloy film of aluminum and lithium is used as the conductive film. Of course, a known MgAg film (an alloy film of magnesium and silver)
May be used. As the cathode material, a conductive film made of an element belonging to Group 1 or 2 of the periodic table or a conductive film to which those elements are added may be used.

When the cathode 714 is formed, the light emitting element 715 is completed. The light emitting element 71 here
Reference numeral 5 denotes a diode formed by the pixel electrode (anode) 710, the light emitting layer 713, and the cathode 714.

It is effective to provide the passivation film 716 so as to completely cover the light emitting element 715. As the passivation film 716, an insulating film including a carbon film, a silicon nitride film, or a silicon nitride oxide film is used, and the insulating film is used in a single layer or in a stacked layer.

At this time, a film having good coverage is preferably used as a passivation film, and a carbon film, particularly, a D film is preferably used.
It is effective to use an LC (diamond-like carbon) film. Since the DLC film can be formed in a temperature range from room temperature to 100 ° C. or lower, it can be easily formed above the light-emitting layer 713 having low heat resistance. In addition, the DLC film has a high blocking effect against oxygen, and the light-emitting layer 713
Can be suppressed. Therefore, the problem that the light emitting layer 713 is oxidized during the subsequent sealing step can be prevented.

Further, a sealing material 717 is provided on the passivation film 716, and a cover material 718 is attached. As the sealing material 717, an ultraviolet curable resin may be used, and it is effective to provide a substance having a moisture absorbing effect or a substance having an antioxidant effect inside. In this embodiment, a cover material 718 having a carbon film (preferably a diamond-like carbon film) formed on both surfaces of a glass substrate, a quartz substrate, or a plastic substrate (including a plastic film) is used.

Thus, a light emitting device having a structure as shown in FIG. 14 is completed. Note that it is effective to continuously process the steps from the formation of the bank 712 to the formation of the passivation film 716 without exposing to the atmosphere using a multi-chamber (or in-line) film forming apparatus. . Further, by further developing, it is also possible to continuously perform processing up to the step of bonding the cover material 718 without releasing to the atmosphere.

Thus, the n-channel type T
FTs 601 and 602, a switching TFT (n-channel TFT) 603, and a current control TFT (n-channel TFT) 604 are formed. The number of masks required in the manufacturing steps up to this point is smaller than that of a general active matrix light emitting device.

That is, the manufacturing process of the TFT is greatly simplified, and an improvement in yield and a reduction in manufacturing cost can be realized.

Further, as described with reference to FIG.
By providing an impurity region overlapping the gate electrode with an insulating film interposed therebetween, n is resistant to deterioration caused by the hot carrier effect.
A channel type TFT can be formed. for that reason,
A highly reliable light-emitting device can be realized.

In this embodiment, only the structure of the pixel portion and the driving circuit is shown. However, according to the manufacturing process of this embodiment, other components such as a signal dividing circuit, a D / A converter, an operational amplifier, a gamma correction circuit, and the like can be used. Can be formed on the same insulator, and a memory and a microprocessor can also be formed.

Further, the light emitting device of this embodiment after performing a sealing (or enclosing) step for protecting the light emitting element will be described with reference to FIG. Note that the reference numerals used in FIG.

FIG. 15A is a top view showing a state in which the light-emitting element has been sealed, and FIG. 15B is a cross-sectional view of FIG. 15A taken along the line CC ′. 80 shown by dotted line
Reference numeral 1 denotes a source side driving circuit, 806 denotes a pixel portion, and 807 denotes a gate side driving circuit. Reference numeral 901 denotes a cover material;
Denotes a first sealant, 903 denotes a second sealant, and a sealant 907 is provided inside the first sealant 902.

Reference numeral 904 denotes wiring for transmitting signals input to the source-side driving circuit 801 and the gate-side driving circuit 807, and a video signal or a clock signal from an FPC (flexible print circuit) 905 serving as an external input terminal. Receive. Although only the FPC is shown here, this FPC has a printed wiring board (P
WB) may be attached. The light emitting device in this specification includes not only the light emitting device body but also an FPC
Alternatively, this also includes a state where the PWB is attached.

Next, a sectional structure will be described with reference to FIG. A pixel portion 806 and a gate driver circuit 807 are formed above the substrate 700.
Is formed by a plurality of pixels including a current control TFT 604 and a pixel electrode 710 electrically connected to its drain. The gate side drive circuit 807 is an n-channel type TF
It is formed using a CMOS circuit (see FIG. 15) in which T601 and p-channel TFT 602 are combined.

The pixel electrode 710 functions as an anode of a light emitting element. Further, banks 712 are provided at both ends of the pixel electrode 710.
Are formed, and a light-emitting layer 713 and a cathode 714 of a light-emitting element are formed over the pixel electrode 710.

The cathode 714 also functions as a common wiring for all pixels, and is electrically connected to the FPC 905 via the connection wiring 904. Further, all elements included in the pixel portion 806 and the gate driver circuit 807 are covered with the cathode 714 and the passivation film 567.

The cover member 901 is attached by the first seal member 902. Note that a spacer made of a resin film may be provided to secure an interval between the cover member 901 and the light emitting element. The inside of the first sealant 902 is filled with a sealant 907. Note that an epoxy resin is preferably used for the first sealant 902 and the sealant 907. Further, it is desirable that the first sealant 902 be a material that does not transmit moisture and oxygen as much as possible. Further, a substance having a moisture absorbing effect or a substance having an antioxidant effect may be contained in the sealing material 907.

[0130] The sealing material 907 provided so as to cover the light emitting element also functions as an adhesive for bonding the cover material 901. In this embodiment, FRP (FRP) is used as the material of the plastic substrate 901a constituting the cover member 901.
iberglass-Reinforced Plastics), PVF (polyvinyl fluoride), mylar, polyester or acrylic can be used.

Further, the cover material 90 is formed by using the sealing material 907.
After bonding, the second sealing material 903 is provided so as to cover the side surface (exposed surface) of the sealing material 907. Second sealing material 90
For 3, the same material as the first sealant 902 can be used.

With the above structure, the light emitting element is sealed with the sealing material 90.
By encapsulating the light-emitting element in the light-emitting element 7, the light-emitting element can be completely shut off from the outside, and a substance such as moisture or oxygen, which promotes deterioration of the light-emitting layer due to oxidation, can be prevented from entering from the outside. Therefore, a highly reliable light emitting device can be obtained.

[Embodiment 8] By applying the present invention, various electro-optical devices (active matrix type liquid crystal display device, active matrix type light emitting device, active matrix type EC display device) can be manufactured. That is, the present invention can be applied to all electronic devices in which the electro-optical device is incorporated in the display unit.

Examples of such electronic devices include a video camera, a digital camera, a projector, a head-mounted display (goggle type display), a car navigation, a car stereo, a personal computer, a portable information terminal (a mobile computer, a mobile phone, an electronic book, etc.). ). An example of them is shown in FIG.
FIG. 17 and FIG.

FIG. 16A shows a personal computer, which comprises a main body 2001, an image input section 2002, and a display section 20.
03, a keyboard 2004 and the like. Display unit 2 of the present invention
003 can be applied.

FIG. 16B shows a video camera, which includes a main body 2101, a display portion 2102, an audio input portion 2103, operation switches 2104, a battery 2105, and an image receiving portion 210.
6 and so on. The present invention can be applied to the display portion 2102.

FIG. 16C shows a mobile computer (mobile computer), which includes a main body 2201, a camera section 2202, an image receiving section 2203, operation switches 2204, a display section 2205, and the like. The present invention can be applied to the display portion 2205.

FIG. 16D shows a goggle type display, which comprises a main body 2301, a display portion 2302, and an arm portion 230.
3 and so on. The present invention can be applied to the display portion 2302.

FIG. 16E shows a player using a recording medium on which a program is recorded (hereinafter, referred to as a recording medium).
3, a recording medium 2404, an operation switch 2405, and the like. This player uses a DVD (D
digital Versatile Disc), CD
And the like, it is possible to perform music appreciation, movie appreciation, games, and the Internet. The present invention can be applied to the display portion 2402.

FIG. 16F shows a digital camera, which includes a main body 2501, a display section 2502, an eyepiece section 2503, operation switches 2504, an image receiving section (not shown), and the like. The present invention can be applied to the display portion 2502.

FIG. 17A shows a front type projector, which includes a projection device 2601, a screen 2602, and the like. The present invention can be applied to the liquid crystal display device 2808 forming a part of the projection device 2601 and other driving circuits.

FIG. 17B shows a rear type projector, which includes a main body 2701, a projection device 2702, and a mirror 270.
3, including a screen 2704 and the like. The present invention relates to a projection device 2
The present invention can be applied to a liquid crystal display device 2808 forming a part of the LCD 702 and other driving circuits.

FIG. 17C is a diagram showing an example of the structure of the projection devices 2601 and 2702 in FIGS. 17A and 17B. Projection devices 2601, 27
02 denotes a light source optical system 2801, mirrors 2802, 280
4 to 2806, dichroic mirror 2803, prism 2807, liquid crystal display device 2808, retardation plate 280
9, the projection optical system 2810. Projection optical system 28
Reference numeral 10 denotes an optical system including a projection lens. In the present embodiment, an example of a three-plate type is shown, but there is no particular limitation, and for example, a single-plate type may be used. In addition, the practitioner may appropriately provide an optical system such as an optical lens, a film having a polarizing function, a film for adjusting a phase difference, and an IR film in an optical path indicated by an arrow in FIG. Good.

FIG. 17D is a diagram showing an example of the structure of the light source optical system 2801 in FIG. 17C. In this embodiment, the light source optical system 2801 includes a reflector 2811, a light source 2812, a lens array 2813,
814, a polarization conversion element 2815, and a condenser lens 2816. Note that the light source optical system shown in FIG. 17D is an example and is not particularly limited. For example, a practitioner may appropriately provide an optical system such as an optical lens, a film having a polarizing function, a film for adjusting a phase difference, and an IR film in the light source optical system.

However, in the projector shown in FIG. 17, a case in which a transmissive electro-optical device is used is shown, and an application example in a reflective electro-optical device and a light emitting device is not shown.

FIG. 18A shows a mobile phone,
01, audio output unit 2902, audio input unit 2903, display unit 2904, operation switch 2905, antenna 2906
And so on. The present invention can be applied to the display portion 2904.

FIG. 18B shows a portable book (electronic book), which includes a main body 3001, display portions 3002 and 3003, a storage medium 3004, operation switches 3005, and an antenna 3006.
And so on. The present invention can be applied to the display units 3002 and 3003.

FIG. 18C shows a display, which includes a main body 3101, a support 3102, a display portion 3103, and the like.
The present invention can be applied to the display portion 3103. The display of the present invention is particularly advantageous when the screen is enlarged, and is advantageous for a display having a diagonal of 10 inches or more (particularly 30 inches or more).

As described above, the applicable range of the present invention is extremely wide, and can be applied to electronic devices in all fields. Further, the electronic apparatus according to the present embodiment can be realized by using any combination of the embodiments 1 to 7.

[0150]

According to the present invention, when the present invention is applied to a manufacturing process of a semiconductor device, the resistance of an impurity region of a semiconductor film can be reduced as compared with the case of heat treatment, and a crystal defect near a TFT channel region can be repaired. Therefore, the characteristics are improved. Also,
In a manufacturing process of a semiconductor device, the number of heat steps can be reduced, so that productivity is increased.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is a three-dimensional view showing one embodiment of the present invention.

FIG. 3 is a side view illustrating an example of a manufacturing process of a semiconductor device.

FIG. 4 is a three-dimensional view showing one embodiment of the present invention.

FIG. 5 is a three-dimensional view showing one embodiment of the present invention.

FIG. 6 is a three-dimensional view showing one embodiment of the present invention.

FIG. 7 is a three-dimensional view showing one embodiment of the present invention.

FIG. 8 is a side view illustrating an example of a manufacturing process of a semiconductor device.

FIG. 9 is a side view illustrating an example of a manufacturing process of a semiconductor device.

FIG. 10 is a side view illustrating an example of a manufacturing process of a semiconductor device.

FIG. 11 is a side view illustrating an example of a manufacturing process of a semiconductor device.

FIG. 12 is a top view illustrating an example of a manufacturing process of a semiconductor device.

FIG. 13 is a side view illustrating an example of a manufacturing process of a semiconductor device.

FIG. 14 is a side view illustrating an example of a structure of a light-emitting device.

15A and 15B are a top view and a side view illustrating an example of a structure of a light-emitting device.

FIG. 16 illustrates an example of a semiconductor device.

FIG. 17 illustrates an example of a semiconductor device.

FIG. 18 illustrates an example of a semiconductor device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 101 Glass substrate 102 Base film 103 Active layer 1031 Source region and drain region 1032 Channel region 104 Gate insulating film 105 Gate electrode 106 Reflector 107 Glass substrate 108 Gate electrode 109 Gate insulating film 110 Semiconductor film 1101 Source region and drain region 1102 Channel region 111 Reflector 201 Laser Oscillator 202 Stepped Glass Plate 203 Cylindrical Lens Array 204 Cylindrical Lens 205 Mirror 206 Condensing Cylindrical Lens 207 Stage 208 Transport Means 209 Glass Substrate 210 Mirror 211 Substrate 212 Base Film 213 Semiconductor Film 214 Insulating film 215 Patterned semiconductor film 216 Conductive film 217 Gate electrode 218 Impurity element is introduced at high concentration Region 219 Region where impurity element is introduced at low concentration 220 Region where impurity is not introduced 221 Stage 222 Air outlet 223 Linear beam 224 Substrate 225 Cylinder 226 Reflector 227 Cylindrical concave mirror 228 Reflector 229 Shade 230 Lamp 231 Reflector 232 reflector

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 21/268 H01L 27/08 331E 27/08 331 29/78 627F 29/786 627G 616L F term (Reference) 2H092 GA59 JA25 JA26 KB04 KB24 KB25 MA05 MA08 MA15 MA27 MA30 MA42 NA21 NA27 NA28 NA29 PA01 PA06 PA07 PA12 RA05 RA10 5C094 AA21 AA43 BA03 BA29 BA43 CA19 DA14 DA15 DB04 EA04 EA07 EB02 GB10 5F048 AC04 BA16 BA07 A07 BB07 A07 BB07 CA04 DA02 DA03 DB02 DB03 DB07 FA06 JA01 5F110 AA30 BB02 BB04 CC02 CC08 DD01 DD02 DD03 DD13 DD14 DD15 DD17 EE01 EE02 EE03 EE04 EE06 EE14 EE23 EE28 EE44 EE45 FF02 FF04 FF28 FF30 FF36 GG13 GG12 GG13 GG02 GG02 HJ13 HJ23 HL06 HM15 NN03 NN04 NN22 NN27 NN34 NN72 PP01 PP02 PP03 PP34 PP35 QQ11 QQ24 QQ25 QQ28

Claims (7)

[Claims] A step of forming a semiconductor film on a surface of a substrate; a step of forming an insulating film on the semiconductor film; a step of forming a gate electrode on the insulating film; A step of adding an impurity element to the semiconductor film, and irradiating first light from a back surface side of the glass substrate,
Irradiating a second light from the front surface side of the substrate, wherein the second light has a part of the first light transmitted through the substrate and the semiconductor film, and a surface of the substrate A method of manufacturing a semiconductor device, wherein the light is reflected by a reflector provided on the side. A step of forming a semiconductor film on the surface of the substrate, a step of forming an insulating film on the semiconductor film, a step of forming a gate electrode on the insulating film, and using the gate electrode as a mask. A step of adding an impurity element to the semiconductor film, and irradiating first light from a back surface side of the glass substrate,
Irradiating a second light from the front surface side of the substrate, wherein the second light has a part of the first light transmitted through the substrate and the semiconductor film, and a surface of the substrate Semiconductor light, which is light reflected by a reflector provided on the side, and wherein the optical path length from the back surface of the substrate to the front surface of the substrate via the reflector is longer than the coherent length of the first light. Method for manufacturing the device. A step of forming a semiconductor film on the surface of the substrate; a step of forming an insulating film on the semiconductor film; a step of forming a gate electrode on the insulating film; A step of adding an impurity element to the semiconductor film, and irradiating first light from a back surface side of the glass substrate,
Irradiating a second light from the front surface side of the substrate, wherein the second light has a part of the first light transmitted through the substrate and the semiconductor film, and a surface of the substrate Light reflected by a reflector installed on the side, and the second light is
A method for manufacturing a semiconductor device, comprising: arriving at a front surface of the substrate through an optical path different from an optical path from the back surface of the substrate to the reflector. 4. The method for manufacturing a semiconductor device according to claim 1, wherein the first light and the second light are laser light or light equivalent thereto. 5. The method according to claim 1, wherein the first light is a second harmonic of a YAG laser, YL.
F laser second harmonic, glass laser second harmonic, Y
A method for manufacturing a semiconductor device, characterized in that the light is light composed of one or a combination of a second harmonic of a VO ₄ laser and an Ar laser. 6. The method for manufacturing a semiconductor device according to claim 1, wherein the substrate is a glass substrate. 7. The method for manufacturing a semiconductor device according to claim 1, wherein the reflector is a cylindrical concave mirror.