JP2002280302A - Method of manufacturing semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form position-controlled crystal grains with high throughput, in a laser irradiation method which is high in interference. SOLUTION: When irradiating a semiconductor film with a laser beam using a laser which is high in interference as a light source, an interference fringe is made intentionally by optical system, so as to form form energy distribution which is cyclic in one direction of the laser beam. The relative transfer distance for each pulse of the laser beam to the above semiconductor film becomes mp±w, when defined that the width of the row of the crystal grains is w, that the pitch of the above cyclic energy distribution is p, and that the natural number is m, and position-controlled crystal grains with high throughput can be formed. Moreover, it becomes possible to crystallize all the region which is irradiated with one pulse of laser beam by optimizing the incident angle of the laser beam and the strength.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device manufactured by including a method of annealing a semiconductor film using laser light (hereinafter, referred to as laser annealing) in a process, and a manufacturing method thereof. Note that the semiconductor device here includes an electro-optical device such as a liquid crystal display device or a light-emitting device, and an electronic device including the electro-optical device as a component.

[0002]

2. Description of the Related Art In recent years, a technique for performing laser annealing on a semiconductor film formed on an insulating substrate such as glass to crystallize or improve crystallinity has been widely studied. Silicon is often used for the semiconductor film. In this specification, means for crystallizing a semiconductor film with laser light to obtain a crystalline semiconductor film is referred to as laser crystallization. Note that in this specification, a crystalline semiconductor film refers to a semiconductor film having a crystallized region, and includes a semiconductor film in which the entire surface is crystallized.

[0003] A glass substrate is less expensive than a synthetic quartz glass substrate which has been often used in the past, and is, for example, 600 × 7.
This has the advantage that a large area substrate such as 20 mm can be easily manufactured. This is the reason for the above research. A laser is preferably used for crystallization because the melting point of the glass substrate is low. The laser can apply high energy only to the semiconductor film without increasing the temperature of the substrate so much. Also, the throughput is much higher than that of the heating means using an electric heating furnace.

Since a crystalline semiconductor film formed by performing laser annealing has high mobility, a thin film transistor (TFT) is formed using the crystalline semiconductor film, and, for example, a thin film transistor is formed on a single glass substrate. It is widely used in monolithic liquid crystal electro-optical devices for producing TFTs for driving pixels and driving circuits.

Further, a pulse laser beam such as an excimer laser having a large output is formed by an optical system so that the shape on the irradiation surface or in the vicinity thereof becomes rectangular or linear, and the laser beam is scanned (or The method of performing laser annealing by moving the irradiation position of the laser beam relative to the irradiation surface) is preferably used because it has high mass productivity and is industrially excellent. Note that in this specification, a laser beam having a rectangular shape on or near the irradiation surface is referred to as a rectangular beam, and a linear laser beam is referred to as a linear beam. The linear beam is included in the rectangular beam. Shall be

In particular, when a linear beam is used, unlike the case of using a spot-shaped laser beam that requires scanning in the front, rear, left, and right directions, the entire irradiation surface is scanned only in a direction perpendicular to the long axis direction of the linear beam. Since the laser irradiation can be performed, mass productivity is high. Scanning is performed in a direction perpendicular to the long axis direction because it is the most efficient scanning direction. Due to this high mass productivity, the use of a linear beam formed by shaping a pulsed excimer laser beam with an appropriate optical system for the laser annealing method is currently becoming the mainstream of manufacturing technology for a liquid crystal display device using a TFT. .

However, the crystalline semiconductor film produced by the laser annealing method is formed by assembling a plurality of crystal grains, and the positions of the crystal grains are random. Could not be formed. But,
The crystalline semiconductor film produced by the laser annealing method was formed by assembling a plurality of crystal grains, and the positions and sizes of the crystal grains were random. A TFT manufactured on a glass substrate is formed by separating the crystalline semiconductor into island-shaped patterning for element isolation. In that case, it was not possible to form the crystal grains by specifying the position and size of the crystal grains. Compared with the inside of the crystal grain, the interface (crystal grain boundary) of the crystal grain has an infinite number of recombination centers and capture centers due to an amorphous structure, crystal defects, and the like. It is known that, when carriers are trapped in the trapping center, the potential of the crystal grain boundary increases and acts as a barrier for the carriers, so that the current transport characteristics of the carriers are reduced. Although the crystallinity of the semiconductor film in the channel formation region has a significant effect on the characteristics of the TFT, it is almost impossible to form the channel formation region with a single crystal semiconductor film by eliminating the influence of the crystal grain boundaries. there were.

[0008] In order to solve such a problem, various attempts have been made to form position-controlled crystal grains in a laser annealing method. Here, a process of solidifying the semiconductor film after irradiating the semiconductor film with laser light will be described.

It takes a certain amount of time until solid-phase nucleation occurs in a liquid semiconductor film completely melted by laser beam irradiation, and countless uniform (or non-uniform) nucleation occurs in a completely melted region. Then, the solidification process of the liquid semiconductor film is completed. In this case, the positions of the crystal grains obtained are random.

Further, even when the semiconductor film is completely melted by the irradiation of the laser beam, a temperature distribution is generated in the semiconductor film, and the semiconductor film is solidified from a low temperature region to form a solid semiconductor region, or the semiconductor film is completely melted. If the solid-state semiconductor region partially remains without performing, crystal growth starts from the solid-state semiconductor region immediately after the irradiation with the laser beam. As described above, it takes some time for nucleation to occur in the completely melted region. Therefore, before nucleation occurs in the completely melted region, the solid-liquid interface, which is the tip of crystal growth, moves in a direction parallel to the film surface of the semiconductor film (hereinafter, referred to as a lateral direction). The crystal grains grow to a length several tens of times the film thickness.

[0011]

For example, a semiconductor film can be crystallized using a YAG laser which is one of typical lasers. At this time, the YAG laser modulates to a second harmonic using a non-linear optical element, and forms a linear beam using an optical system. The energy distribution of the linear beam is a Gaussian distribution in the short axis direction and uniform in the long axis direction. Such a linear beam 50
When 1 is irradiated to the one-pulse semiconductor film, crystal grains 506 having a width of several μm are formed as rows 508 in the long axis direction of the linear beam, and regions other than the rows of crystal grains 508 are regions where fine crystal grains are formed ( (Microcrystalline region) 505. (FIG. 5) This is because, since the energy distribution is a Gaussian distribution in the short axis direction of the linear beam, a region that is too high and a region that is too low than the energy density suitable for crystallization are microcrystalline regions 505,
From a region having an energy density 507 suitable for crystallization,
This is probably because lateral growth is performed toward a region where the melting time is long and the temperature is high.

In order to crystallize the whole semiconductor film using a linear beam, it is necessary to repeatedly irradiate the linear beam while shifting it by several μm, which is the width of a crystal grain. FIG. 6 shows this state. FIG. 6 is a schematic view of a cross section of a semiconductor film obtained by irradiation with the first pulse of the laser light 601.
It is shown in (A). Here, 606 indicates laterally grown crystal grains, and 605 indicates fine crystal grains. FIG. 6B is a schematic view of a cross section of the semiconductor film obtained by irradiation with the second pulse of the laser light 602 shifted by the width w of the crystal grains 606 in the direction of 604. Then, the movement of the width w of the crystal grain 606 and the irradiation of the laser beam are repeated, and a schematic diagram of a cross section of the semiconductor film obtained by irradiation of the few pulses 603 is
(C). For example, YAG with a frequency of 1 kHz
Using a laser, irradiating 1 pulse of laser light, width 1μ
When a row of m crystal grains is formed, only a 1 mm wide semiconductor film is crystallized per second. On the other hand, the size of a substrate to be used is increasing. For example, such an irradiation method requires 10 minutes to crystallize a semiconductor film formed on a substrate of 600 × 720 mm. As described above, even if a high-frequency laser oscillator is used, the relative movement distance of the laser light with respect to the semiconductor film for each pulse is only the width w of the crystal grain, so that the high-frequency characteristics cannot be utilized at all.

The YAG laser is a coherent light having a very high coherence. The coherent length of an excimer laser is several μm to several tens μm, while the coherent length of a YAG laser is around 10 mm. Therefore, it has been difficult to form a laser beam having a uniform energy distribution on or near the irradiation surface.

Accordingly, the present invention provides a laser irradiation method using a laser having high coherence, wherein a semiconductor film having crystal grains whose positions are controlled is formed at a high throughput, and the semiconductor film obtained in this manner is used. It is an object to provide a method for manufacturing a semiconductor device by using the method.

[0015]

The laser light has the characteristic that even if it is emitted from the same light source, it does not interfere with each other if the optical path difference is longer than the coherent length. Compared to excimer lasers, YAG lasers have much higher coherence. Coherent length of excimer laser is several μm to several tens μ
m, whereas the coherent length of the YAG laser is 1
It is around 0 mm.

Accordingly, the present invention provides a method of forming a laser beam having a periodic energy distribution by intentionally forming interference fringes utilizing the high coherence of a YAG laser, and irradiating the semiconductor film with the laser beam. The semiconductor film may be laterally grown by forming a temperature distribution.

The present invention will be described with reference to FIG. The laser beam 101 has a periodic energy distribution due to the effect of interference. Such a distribution can be obtained, for example, by dividing laser light emitted from the same light source into a plurality of parts with a slit, a half mirror, or the like, and combining the divided parts on the irradiation surface or in the vicinity thereof. In order to maintain the coherence of the laser light, the optical path difference between the plurality of laser lights is shorter than the coherent length of the laser light.

Many interference fringes are formed in the laser beam due to the effect of interference. The interference fringes are formed because the energy density of the laser beam has a wave-like distribution. When the semiconductor film 104 disposed on the irradiation surface is irradiated with such a laser beam 101, lateral growth occurs in a region irradiated with an energy density suitable for crystallization, and many rows 106 of crystal grains due to the lateral growth are formed. It is formed.

Here, in the laser beam 101, the interval between the rows of crystal grains on both sides of the portion having the highest energy density is p1, and the interval between the rows of crystal grains on both sides of the portion having the lowest energy density of the linear beam. Is defined as p2. The distances p1 and p2 between the rows 106 of crystal grains adjacent to each other depend on the angle of incidence of the divided laser light on the irradiation surface. In order to complement a space between adjacent crystal grains, for example, the semiconductor film may be irradiated with laser light again by moving the laser light in parallel by the width w of the crystal grain row 106. However, such an irradiation method does not improve the throughput at all.

Therefore, in order to dramatically improve the throughput, for example, the parallel movement distance is set to the width w of the row of crystal grains.
Instead, p ± w. Here, p is the pitch of the energy distribution, and p = p1 + p2. By repeating the parallel movement at p ± w and the laser irradiation, almost all regions of the semiconductor film can be completely filled with the laterally grown crystal grains. However, this is possible when w (n−1) ≧ p ± w (1) as the number n of the pitches of the periodic energy distribution in the laser beam. Of course, the parallel movement distance is m
If p ± w (where m is a natural number), the throughput can be further improved.

For example, as shown in FIG. 2, when a semiconductor film is irradiated with a laser beam 202 having a periodic energy distribution, crystal grains 20 formed by lateral growth are formed.
Assume that a semiconductor film having 6 and microcrystalline grains 205 is obtained. (FIG. 2A) and the second pulse laser beam 20
2 is moved by p + w relative to the semiconductor film to irradiate the semiconductor film as shown in FIG. 2B, and further moved by p + w relative to the semiconductor film to obtain 3. When the laser beam 203 of the pulse is irradiated, FIG.
A semiconductor film as shown in (C) is obtained. in this way,
When the semiconductor film is moved by p ± w with respect to each irradiation of the laser light, the throughput can be improved.

In a special case such as p1 = p2,
The number of rows 106 of crystal grains at equal intervals is doubled,
Since the conditional expression can be considered by replacing n in the expression (1) with 2n, it is possible to further improve the throughput.

In the irradiation method of the present invention, a region in which crystallization is performed and crystal grains are formed by lateral growth is irradiated with laser light many times. FIG. 4 shows a graph of the absorption coefficient with respect to the wavelength of the amorphous silicon film and the crystalline silicon film. From FIG. 4, at 370 to 650 nm, the absorption coefficient of the amorphous silicon film is higher than that of the crystalline silicon film. Therefore, 370-650n
When a laser beam having a wavelength in the range of m is used, the amorphous silicon film is more absorbed than the crystalline silicon film. Therefore, if an appropriate energy is selected, laser crystallization can be performed without affecting the crystallization region. it can.

The pitch of the interference fringes formed by the plurality of divided laser beams can be adjusted to the width of the crystal grains. As shown in FIG. 7A, when the laser beam 1 and the laser beam 2 are incident, interference fringes as shown in FIG. 7B are formed on the irradiation surface. At this time, the pitch p of the interference fringes depends on the incident angle θ of the laser beam. By optimizing the incident angle θ, as shown in FIG. 7C, the entire area irradiated with the laser beam is completely filled with the crystal grains having the width w. At this time, the pitch p of the interference fringes is twice the width w of the crystal grains. Therefore, the incident angle θ of the laser light is represented by sin θ = λ / p (where p = 2w) (2) from FIG. As described above, when one pulse of the laser light is irradiated at the incident angle θ that satisfies the expression (2), the region irradiated with the laser light is completely filled with the crystal grains. Therefore, every time the laser light is irradiated, the laser light can be moved relative to the semiconductor film by the width or the length of the laser light in the direction in which the periodic energy distribution of the laser light is formed. Possible, and the throughput is further improved.

However, if the energy densities of the divided laser beams are completely equal, the energy density at the nodes of the interference fringes becomes zero, and a temperature gradient suitable for crystallization may not be obtained in the semiconductor film. In this case, it is preferable to create mutually independent components in the polarization components of the plurality of laser beams to suppress the degree of interference. When a polarized laser beam is used as a light source, an element such as a λ / 2 plate or a Faraday rotator is used in an optical path of at least one of the divided laser beams to reduce the difference in the intensity of interference. It is desirable. By using such an element and rotating the polarization component of at least one laser beam at an angle greater than 0 degree and less than 90 degrees, even if a plurality of laser beams are combined on or near the irradiation surface, orthogonal polarization is obtained. Since the components do not interfere with each other, it is possible to obtain an energy distribution that does not generate a node where the energy density becomes zero.

The present invention uses a laser having high coherence, intentionally forms interference fringes to form a periodic energy distribution in laser light, and irradiates the semiconductor film with the laser light to efficiently control the position. Characterized in that they form formed crystal grains.

At this time, it is desirable that the laser beam is shaped into a rectangular beam, particularly a linear beam by an optical system, and is irradiated. It should be noted that the term “linear” here does not mean a “line” in a strict sense, but means a rectangle (or a long ellipse) having a large aspect ratio. For example, an aspect ratio of 10 or more (preferably 100 to 1000)
0).

As the laser, a generally known laser can be used, and a YAG laser (usually Nd: YAG) is used.
Laser), Nd: YLF laser, Nd: YVO ₄
Laser, Nd: YAlO ₃ laser, ruby laser, T
i: A sapphire laser, a glass laser, or the like can be used. In particular, a YAG laser which is superior in pulse energy is preferable.

However, since the fundamental wave (first harmonic) of the YAG laser has a long wavelength of 1064 nm, the second harmonic (532 nm) is used. The formation of this harmonic may be in accordance with a known technique.

Further, a Q switch method (Q modulation switch method) often used in a YAG laser may be used. This is from the state where the Q value of the laser resonator is sufficiently low,
This is a method of outputting a steep pulse laser having a very high energy value by rapidly increasing the Q value. In addition, by using the Q-switch method, high-frequency pulse oscillation can be performed. This is a known technique.

The present invention realizes formation of a semiconductor film having position-controlled crystal grains with high throughput in a laser irradiation apparatus having a lower running cost and a laser irradiation method using the same as compared with the prior art. Things.

By obtaining a crystalline semiconductor film having a large crystal grain size, the performance of the semiconductor device can be greatly improved. For example, taking a TFT as an example,
By increasing the crystal grain size, the number of crystal grain boundaries that can be included in the channel formation region can be reduced. That is,
It is also possible to manufacture a TFT having one, preferably zero crystal grain boundaries in the channel formation region. Also,
Since individual crystal grains have crystallinity that can be regarded as substantially a single crystal, high mobility (field-effect mobility) equal to or higher than that of a transistor using a single crystal semiconductor
It is also possible to get

Furthermore, since the number of times carriers cross the crystal grain boundary can be extremely reduced, the on-current value (TFT
It is also possible to reduce variations in the drain current value flowing when the TFT is in the ON state, the OFF current value (the drain current value flowing when the TFT is in the OFF state), the threshold voltage, the S value, and the field effect mobility. Become.

[0034]

[First Embodiment] FIG. 3 is a diagram showing an example of the configuration of a laser irradiation apparatus according to the present invention. This laser irradiation device includes a laser oscillator 301, a nonlinear optical element 302,
Optical system 303 for forming laser light into a linear shape, irradiation surface 304
have. The laser oscillator 301 oscillates linearly polarized laser light and is modulated by the nonlinear optical element 302 to a second harmonic. An optical system for forming a linear laser beam on the irradiation surface 304 includes, for example, a beam expander 3031 that combines a cylindrical lens with a long focal length for enlarging the laser beam, and narrowly condenses the laser beam. Focal length cylindrical lens 3 for
032 is used. Here, the reason for using a cylindrical lens having a long focal length is to suppress aberration as much as possible and to obtain a beam having a uniform energy distribution on the irradiation surface 304. A cylindrical array lens 3033 is arranged in front of the cylindrical lens 3032, and divides a laser beam into a plurality of laser beams. These split laser beams are transmitted by a cylindrical lens 3032.
The laser beam is synthesized at or near the irradiation surface 304 and shaped into a laser beam having interference fringes with controlled energy distribution.
Further, a reflection mirror 3034 is provided above the cylindrical array lens 3033 so that the traveling direction of the laser light can be changed. The irradiation surface 304 is provided with a stage that operates in a direction perpendicular to the long axis direction of the linear beam formed by the optical system 303.

When a semiconductor film is irradiated with laser light using such a laser irradiation apparatus, a row of crystal grains formed by n lateral growths is formed by one irradiation. When the pitch of the periodic energy distribution of the laser light is p and the width of the row of crystal grains is w, if the moving distance of the laser light is p ± w, high throughput can be realized. Of course, if mp ± w (where m is a natural number), the throughput can be further improved.

If a TFT is manufactured using the crystalline semiconductor film formed in this manner, the TFT has good electrical characteristics.

[Embodiment 2] FIG. 8 is a diagram showing an example of the configuration of a laser irradiation apparatus according to the present invention. This laser irradiation device includes a laser oscillator 801, a nonlinear optical element 802, an irradiation surface 8
07 or its vicinity, an optical system 803 to 80 for shaping into a laser beam having a periodic energy distribution
6. It has an irradiation surface 807. The laser oscillator 801 oscillates linearly polarized laser light and is modulated by the nonlinear optical element 802 to a second harmonic. An optical system for shaping a laser beam having a periodic energy distribution on or near the irradiation surface 807 includes, for example, beam expanders 803 and 804 combined with a long focal length cylindrical lens for enlarging the laser beam. And a mirror 805 for splitting the laser light in two directions, mirrors 806a and 806b for synthesizing the laser light split in the two directions on or near the irradiation surface, and a λ / 2 plate 810 for rotating the polarization direction. The laser light is synthesized by the mirrors 805 and 806 on or near the irradiation surface 204, and shaped into laser light having interference fringes with controlled energy distribution. When the λ / 2 plate 810 is appropriately rotated, the interference fringes formed on or near the irradiation surface do not have a node having an energy density of zero. The irradiation surface 807 is provided with a stage 808 that operates in a direction 809 parallel to the direction in which the periodic energy distribution of the laser light formed by the optical systems 803 to 806 is formed.

The mirrors 806a and 806b are
The laser beams divided into two directions by the laser beam 5 are incident on the irradiation surface at an incident angle θ satisfying the expression (2) on the irradiation surface. Also, the mirror 80
Reference numeral 5 designates a λ / 2 plate 810 for rotating the polarization direction in order to divide the laser light in two directions with the same intensity, thereby preventing the energy distribution of interference fringes on the irradiation surface from becoming zero.

Of course, when the energy densities of the laser beams divided in two directions by the mirror 805 do not completely match, even if the λ / 2 plate 810 is not provided, the interference fringes formed on the irradiation surface or in the vicinity thereof Has no nodes with zero energy density.

The crystalline semiconductor film obtained by such laser annealing can be filled with crystal grains formed by lateral growth. In addition, since the laser beam can be moved for each beam width, the throughput is improved and the process time can be reduced. And
Using the crystalline semiconductor film thus formed, TF
When T is manufactured, the electrical characteristics of the TFT become good.

The present invention having the above configuration will be described in more detail with reference to the following embodiments.

[0042]

[Embodiment 1] An embodiment of the present invention will be described.

FIG. 3 is a diagram showing an example of the configuration of the laser irradiation apparatus of the present invention. This laser irradiation device is a laser oscillator 3
01, a non-linear optical element 302, an optical system 303 for shaping a laser beam into a linear shape, and an irradiation surface 304. The laser oscillator 301 oscillates linearly polarized laser light and is modulated by the nonlinear optical element 302 to a second harmonic. Irradiation surface 30
The optical system for forming a linear laser beam in 4 includes, for example, a beam expander 3031 combining a cylindrical lens with a long focal length for enlarging the laser beam long, and a beam expander 3031 for condensing the laser beam thinly. A long focal length cylindrical lens 3032 is used. A cylindrical array lens 3033 is arranged in front of the cylindrical lens 3032, and divides a laser beam into a plurality of laser beams. These split laser beams are combined by the cylindrical lens 3032 on or near the irradiation surface 204, and shaped into laser beams having interference fringes with controlled energy distribution. A reflection mirror 303 is provided above the cylindrical array lens 3033.
4 is provided so that the traveling direction of the laser beam can be changed. The irradiation surface 304 is provided with a stage that operates in a direction perpendicular to the long axis direction of the linear beam formed by the optical system 303.

In the present embodiment, a flash lamp pumped YAG laser having a frequency of 30 Hz is used as the laser oscillator 301. The laser light oscillated from the YAG laser is modulated to the second harmonic by the nonlinear optical element 302, and the energy density becomes 800 mJ / pulse. The focal length of the cylindrical lens 3032 is 200 mm. The cylindrical array lens 3033 has a focal length of 200 m.
An array of eight m cylindrical lenses is used. The width of the cylindrical lens is 2 mm and the length is 6
0 mm. The irradiation surface 304 is located at the focal position of the cylindrical lens 3032, that is, the cylindrical lens 3
It is arranged 200 mm rearward from 032. By providing such an optical system, the irradiation surface 304 has a number of interference fringes of 50.
In this case, a linear beam with p = 0.05 mm can be formed. At this time, the width w of the crystal grain formed by the lateral growth is about 1 μm. By substituting these values into equation (1), left side = w × (n−1) = 1 μm × (50-1) ≒ 0.05 mm right side = p ± w = 0.05 mm ± 1 μm ≒ 0.05 mm Satisfies the right side. Therefore, it is possible to fill almost the entire surface of the semiconductor film with crystal grains formed by lateral growth.

Therefore, if the moving distance of the laser beam is p ± w, a high throughput can be realized. Of course, if the number n of rows of crystal grains formed by one irradiation is sufficiently large and the moving distance of the laser beam can be mp ± w (where m is a natural number), the throughput can be further improved. Becomes possible.

In this embodiment, the laser beam is irradiated with p + w = 0.05 mm + 1 μm ≒ 0.05 mm relative to the irradiation surface.
After moving by the distance, the next pulse was irradiated. The frequency of the laser oscillator in this embodiment is 30H
Because of z, the moving speed of the stage is 0.05 ÷ (1/30) = 1.5 [mm / s]. However, if the moving distance of the irradiation surface between the pulses of the laser light completely matches p, it is not possible to completely fill the gap between the crystal grains formed by the lateral growth. It is necessary to fine-tune s.

When laser annealing is performed by such an irradiation method, the throughput is improved and the process time can be reduced. Further, the crystalline semiconductor film obtained by such laser annealing can be filled with crystal grains formed by lateral growth. Then, when a TFT is manufactured using the crystalline semiconductor film formed in this manner, the electrical characteristics of the TFT are improved.

[Embodiment 2] In this embodiment, a crystalline semiconductor film formed by performing laser annealing using the optical system shown in FIG. 9 will be described.

FIG. 9 is a view showing an example of the configuration of the laser irradiation apparatus of the present invention. However, the same reference numerals are used for the portions corresponding to FIG. This laser irradiation device has a laser oscillator 30.
1, a nonlinear optical element 302, an optical system 953 for linearly forming a laser beam, and an irradiation surface 304. The laser oscillator 301 oscillates linearly polarized laser light and is modulated by the nonlinear optical element 302 to a second harmonic. Irradiation surface 304
Optical systems for forming linear laser light in
For example, a beam expander 3031 combined with a long focal length cylindrical lens for extending laser light for a long time, and a long focal length cylindrical lens 3032 for condensing laser light finely are used. Then, the irradiation surface 30 is formed by the cylindrical lens 3032.
4 or the vicinity thereof, and shaped into a laser beam having interference fringes with controlled energy distribution. Further, a reflection mirror 303 is provided above the cylindrical lens 3032.
4 is provided so that the traveling direction of the laser beam can be changed.

In this embodiment, a flash lamp pumped YAG laser having a frequency of 30 Hz is used as the laser oscillator 301. The laser light oscillated from the YAG laser is modulated by the nonlinear optical element 302 to the second harmonic. The focal length of the cylindrical lens 3032 is 400 mm.
The irradiation surface 304 is located at the focal position of the cylindrical lens 3032, that is,
It is arranged 0 mm behind. Further, in this example, in order to form interference fringes in the semiconductor film, the silicon wafer 951 was placed on the substrate placed on the irradiation surface. Since there was a slight gap between the substrate and the silicon wafer, diffraction occurred, and a periodic intensity distribution was formed in the major axis direction of the laser beam. (FIG. 10B) When the semiconductor film is irradiated with one pulse of such a laser beam, a crystalline semiconductor film having crystal grains 1001 and microcrystal grains 1002 as shown in FIG. 10C is formed. Become.

In this embodiment, 1737 is used as the semiconductor film.
A 50 nm-thick silicon oxynitride film (composition ratio Si = 32%, O
= 59%, N = 7%, H = 2%) and a film thickness of 100 nm
Silicon oxynitride film (composition ratio: Si = 32%, O = 27
%, N = 24%, H = 17%).
nm of an amorphous silicon film was formed. Then, in order to improve the laser resistance of the film, the film was exposed to a nitrogen atmosphere at a temperature of 500 ° C. for one hour to reduce the amount of hydrogen contained.

FIG. 11 shows a crystalline semiconductor film obtained by irradiating such a semiconductor film with one pulse of laser light using the optical system shown in FIG. 9, and FIG. 12 is a schematic diagram thereof. It can be seen that the crystal grains are laterally growing from a low temperature region to a high temperature region. 11 and 12, the width w of the crystal grain and the pitch p of the interference fringes are p = 2w
Meet the relationship.

When a TFT is manufactured using the crystalline semiconductor film thus formed, the electrical characteristics of the TFT are improved.

Third Embodiment An embodiment different from the first and second embodiments of the present invention will be described.

FIG. 13 is a diagram showing an example of the configuration of the laser irradiation apparatus of the present invention. This laser irradiation apparatus includes an optical system 803 to 806 for shaping a laser beam having a periodic energy distribution at or near a laser oscillator 801, a nonlinear optical element 802, an irradiation surface 807, and an irradiation surface 8.
07. The laser oscillator 801 oscillates linearly polarized laser light and is modulated by the nonlinear optical element 802 to a second harmonic. An optical system for shaping a laser beam having a periodic energy distribution on or near the irradiation surface 807 includes, for example, beam expanders 803 and 804 combined with a long focal length cylindrical lens for enlarging the laser beam. And a mirror 805 for splitting the laser light in two directions, and a mirror 80 for synthesizing the laser light split in the two directions on or near the irradiation surface.
6a and 806b are arranged. The laser light is synthesized on or near the irradiation surface 807 by the mirrors 805 and 806, and shaped into laser light having interference fringes with controlled energy distribution. The optical system 80 is provided on the irradiation surface 807.
A stage 808 is provided that operates in a direction 809 parallel to the direction in which the periodic energy distribution of the laser light formed in steps 3 to 806 is formed.

If laser annealing is performed by such an irradiation method, the throughput can be improved and the process time can be shortened. Further, the crystalline semiconductor film obtained by such laser annealing can be filled with crystal grains formed by lateral growth. Then, when a TFT is manufactured using the crystalline semiconductor film formed in this manner, the electrical characteristics of the TFT are improved.

[Embodiment 4] FIG. 8 is a diagram showing an example of the configuration of a laser irradiation apparatus according to the present invention. However, the same reference numerals are used for the portions corresponding to FIG. This laser irradiation apparatus includes an optical system 803 to 8 for shaping a laser beam having a periodic energy distribution at or near a laser oscillator 801, a nonlinear optical element 802, an irradiation surface 807, or the like.
06, and an irradiation surface 807. Laser oscillator 801
Oscillates linearly polarized laser light, and outputs the nonlinear optical element 802.
Is modulated to the second harmonic. An optical system for shaping a laser beam having a periodic energy distribution on or near the irradiation surface 807 includes, for example, beam expanders 803 and 804 combined with a long focal length cylindrical lens for enlarging the laser beam. When,
A mirror 805 for splitting laser light in two directions, mirrors 806a and 806b for synthesizing the laser light split in two directions on or near an irradiation surface, and a λ / 2 plate 810 for rotating the polarization direction are arranged. The laser light is synthesized by the mirrors 805 and 806 on or near the irradiation surface 204, and shaped into laser light having interference fringes with controlled energy distribution. Further, the interference fringe formed on or near the irradiation surface by the λ / 2 plate 810 does not have a node having an energy density of zero. In addition, on the irradiation surface 807,
A direction 809 parallel to the direction in which the periodic energy distribution of the laser light formed by the optical systems 803 to 806 is formed.
Stage 808 is provided.

The mirrors 806a and 806b
The laser beams divided into two directions by the laser beam 5 are incident on the irradiation surface at an incident angle θ satisfying the expression (2) on the irradiation surface. Also, the mirror 80
Reference numeral 5 designates a λ / 2 plate 810 for rotating the polarization direction in order to divide the laser light in two directions with the same intensity, thereby preventing the energy distribution of interference fringes on the irradiation surface from becoming zero.

In this embodiment, a YAG laser is used as the laser oscillator 801, and the second
Laser light modulated to a harmonic of 532 nm is used. Here, the incident angle θ of the laser light is calculated. When the width of the formed crystal grain is estimated to be 0.1 to 5 μm,
From equation (2), sin θ = 532 nm / (1 to 10 μm)） θ ≒ 3 to 32 degrees.

A crystalline semiconductor film obtained by irradiation with a laser beam having such an incident angle can be filled with crystal grains formed by lateral growth. In addition, since the laser beam can be moved for each beam width, the throughput is improved and the process time can be reduced. Then, when a TFT is manufactured using the crystalline semiconductor film formed in this manner, the electrical characteristics of the TFT are improved.

Embodiment 5 In this embodiment, a method for manufacturing an active matrix substrate will be described with reference to FIGS.

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 as the substrate 300, a quartz substrate, a silicon substrate, a metal substrate, or a stainless steel substrate on which an insulating film is formed may be used. Further, a plastic substrate having heat resistance enough to withstand the processing temperature of 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, a semiconductor film 302 is formed on the base film. As the semiconductor film 302, 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 the laser crystallization method is patterned into a desired shape to form semiconductor layers 402 to 406. Of course, in addition to the laser crystallization method, it is performed in combination with other known crystallization treatments (such as a thermal crystallization method using an RTA or a furnace annealing furnace or the like, a thermal crystallization method using a catalyst such as nickel). Is also good.

In the laser crystallization method, a pulse oscillation type or continuous emission type excimer laser, YAG laser, YV
An O ₄ 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 30 to 300 Hz, and the laser energy density is set to 100 to 800 mJ / cm ² (typically, 200 to 700 mJ / cm ² ).
cm ² ). When a YAG laser is used, its second harmonic is used to set the pulse oscillation frequency to 1 to 300 Hz, and the laser energy density is set to 300 to 1000 mJ / cm ^2.
(Typically 350 to 800 mJ / cm ² ). A linearly focused laser beam having a width of 100 to 1000 μm, for example, 400 μm, is irradiated over the entire surface of the substrate.

In this embodiment, a plasma CVD method is used.
After forming a 55 nm amorphous silicon film, a crystalline silicon film is formed by a laser crystallization method to which the laser irradiation method of the present invention is applied. Then, semiconductor layers 402 to 406 are formed by patterning the crystalline silicon film using a photolithography method.

After forming the semiconductor layers 402 to 406, T
A small amount of impurity element (boron or phosphorus) may be doped in order to control the threshold value of FT.

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. 14B, a first conductive film 408 having a thickness of 20 to 100 nm and a second conductive film 4 having a thickness of 100 to 400 nm are formed on the gate insulating film 407.
09 is laminated. In this embodiment, a first conductive film 408 made of a TaN film having a thickness of 30 nm and a
A second conductive film 409 made of a W film was formed by lamination.
The TaN 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.

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.

Thereafter, 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, by making the shape of the mask made of resist suitable,
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 °. Thus, the first-shaped conductive layers 417 to 422 (the first conductive layers 417 a to 422 a and the second conductive layers 417 b to 422) 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 n-type impurity element to the semiconductor layer. (FIG. 15A) 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 × 1.
0 ^{13 to} 5 × 10 ¹⁵ / cm ² and an acceleration voltage of 60 to 10
The operation is performed at 0 keV. In this embodiment, the dose is 1.5
X 10 ¹⁵ / cm ² , and the acceleration voltage was set to 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 layers 417 to 421 serve as a mask for the impurity element imparting n-type, and the first high-concentration impurity regions 30 are self-aligned.
6 to 310 are formed. First high concentration impurity region 30
To 6 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, without removing the resist mask, a second doping process is performed as shown in FIG. In this case, the dose is lower than that of the first doping process, and an n-type impurity element is introduced at a high acceleration voltage of 70 to 120 keV. In this embodiment, the dose is set to 1.5 × 10 ¹⁴ / cm ² and the acceleration voltage is set to 90 keV. The second doping process uses the second shape conductive layers 428 to 433 as a mask,
The impurity element is also introduced into the semiconductor layer below the second conductive layers 428b to 433b, and the second high concentration impurity regions 423a to 427a and the low concentration impurity regions 42 are newly added.
3b to 427b are formed.

Next, after removing the resist mask, new masks 434a and 434a are formed.
After forming 34b, 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.

Next, 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. 16A)

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. 16B) 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. 16C, heat treatment is performed to recover the crystallinity of the semiconductor layers and activate the impurity elements added to the respective semiconductor layers. This heat treatment is performed by a thermal annealing method using a furnace annealing furnace. As a thermal annealing method, an oxygen concentration of 1 pp
m, preferably 0.1 ppm or less in a nitrogen atmosphere at 400 to 700 ° C., typically 500 to 550 ° C. In this example, the activation treatment was performed by heat treatment at 550 ° C. for 4 hours. . In addition to the thermal annealing method, a laser annealing method or a rapid thermal annealing method (RTA)
Law) can be applied.

Further, heat treatment may be performed before forming the first interlayer insulating film. However, when the wiring material used is weak to heat, an active layer is formed after an interlayer insulating film (an insulating film containing silicon as a main component, for example, a silicon nitride film) is formed to protect the wiring and the like as in this embodiment. It is preferable to carry out a chemical treatment.

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 perform a step of hydrogenating 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.

When a laser annealing method is used as the activation treatment, it is preferable to irradiate a laser beam such as an excimer laser or a YAG laser after performing the above hydrogenation.

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.

Further, a film whose surface is flattened may be used as second interlayer insulating film 462. 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.

In the 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. 17) By 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
1 includes a channel formation region 423c, a low-concentration impurity region 423b (a GOLD region) overlapping with a first conductive layer 428a which forms part of a gate electrode, and a high-concentration impurity region 423a functioning as a source or drain region. ing. A p-channel TFT 5 connected to the n-channel TFT 501 via an electrode 466 to form a CMOS circuit
02 has a channel formation 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. Also, an n-channel TFT 50
3 includes a channel formation region 425c, a low-concentration impurity region 425b (GOLD region) overlapping with the first conductive layer 430a which forms part of the gate electrode, and a high-concentration impurity region 425a functioning as a source or drain region. are doing.

The pixel TFT 504 in the pixel portion includes a channel forming 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.
have. 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. The storage capacitor 505 includes an electrode (438) using the insulating film 444 as a dielectric.
a and 438b), and the semiconductor layers 447a to 447c.
And formed.

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. 18 is a top view of the pixel portion of the 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. 17 is a chain line AA ′ in FIG.
It corresponds to the cross-sectional view cut by. The dashed line BB ′ in FIG. 17 corresponds to the cross-sectional view cut along the dashed line BB ′ in FIG.

This embodiment can be freely combined with Embodiments 1 to 4.

[Embodiment 6] In this embodiment, a process of manufacturing a reflective liquid crystal display device from the active matrix substrate manufactured in Embodiment 5 will be described below. Figure 19 for explanation
Is used.

First, according to the fifth embodiment, after obtaining the active matrix substrate in the state shown in FIG. 17, 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.
8, 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. 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 stacked 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 counter 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. 19 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 Embodiments 1 to 5.

[Embodiment 7] In this embodiment, an example in which a light emitting device is manufactured using the present invention will be described. In this specification, a light emitting device is a general term for a display panel in which a light emitting element formed on a substrate is sealed between the substrate and a cover material, and a display module in which an IC is mounted on the display panel. is there. 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. 20 is a sectional view of the light emitting device of this embodiment. 20, the switching TFT 603 provided on the substrate 700 is the same as the n-channel TFT 50 shown in 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 forming regions are formed, a single gate structure in which one channel forming region is formed or a triple gate structure in which three channel forming regions are formed. good.

The driving circuit provided on the substrate 700 is shown in FIG.
7 CMOS circuits. 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. Although the present embodiment has a single gate structure, it may have a double gate structure or a triple gate structure.

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. Although the present embodiment has a single gate structure, it may have a double gate structure or a triple gate structure.

A wiring 706 is a source wiring (corresponding to a current supply line) of the current control TFT, and an electrode 707 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 step due to the TFT using the flattening film 711 made of resin. Since a light-emitting layer formed later is very thin, light emission failure may occur due to 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, the resistivity is reduced by adding carbon particles or metal particles to the insulating film used as the material of the bank 712 to suppress the generation of static electricity. At this time, the resistivity is 1 × 10 ⁶ to 1 × 1.
The addition amount of the carbon particles and 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. 20, 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 20-nm-thick copper phthalocyanine (CuPc) film is provided as a hole-injecting layer, and
It has a stacked 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 less, 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. 20 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.

In this manner, the n-channel TFTs 601, 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 process up to this point is
Less than a typical 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 configuration of the pixel portion and the drive 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 γ 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 the sealing (or enclosing) step for protecting the light emitting element will be described with reference to FIG. The reference numerals used in FIG. 20 are referred to as needed.

FIG. 21A is a top view showing a state in which the light emitting element has been sealed, and FIG. 21B is a cross-sectional view of FIG. 21A taken along the line CC ′. 81 shown by dotted line
5 is a source side drive circuit, 816 is a pixel portion, and 817 is a gate side drive circuit. 901 is a cover material, 902
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 driver circuit 815 and the gate driver circuit 817, 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 cross-sectional structure will be described with reference to FIG. A pixel portion 816 and a gate driver circuit 817 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 817 is an n-channel type TF
It is formed using a CMOS circuit (see FIG. 14) 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 816 and the gate driver circuit 817 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.

[0136] 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 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 enclosing 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.

Note that this embodiment can be freely combined with Embodiments 1 to 5.

[Embodiment 8] By applying the present invention, CMOS circuits and pixel portions formed by carrying out the present invention can be various electro-optical devices (active matrix liquid crystal displays,
Active matrix type EC display and active matrix type light emitting display). 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 equipment 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 or an electronic book, etc.). ). An example of them is shown in FIG.
FIG. 23 and FIG.

FIG. 22A shows a personal computer, which includes a main body 3001, an image input section 3002, and a display section 30.
03, a keyboard 3004 and the like. Display unit 3 of the present invention
003 can be applied.

FIG. 22B shows a video camera, which includes a main body 3101, a display portion 3102, an audio input portion 3103, operation switches 3104, a battery 3105, and an image receiving portion 310.
6 and so on. The present invention can be applied to the display portion 3102.

FIG. 22C shows a mobile computer (mobile computer), which includes a main body 3201, a camera section 3202, an image receiving section 3203, operation switches 3204, a display section 3205, and the like. The present invention can be applied to the display portion 3205.

FIG. 22D shows a goggle type display, which comprises a main body 3301, a display section 3302, and an arm section 330.
3 and so on. The present invention can be applied to the display portion 3302.

FIG. 22E shows a player that uses a recording medium (hereinafter, referred to as a recording medium) on which a program is recorded, and includes a main body 3401, a display portion 3402, and a speaker portion 340.
3, a recording medium 3404, an operation switch 3405, 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 3402.

FIG. 22F shows a digital camera, which includes a main body 3501, a display section 3502, an eyepiece section 3503, operation switches 3504, an image receiving section (not shown), and the like. The present invention can be applied to the display portion 3502.

FIG. 23A shows a front type projector, which includes a projection device 3601, a screen 3602, and the like. The present invention can be applied to the liquid crystal display device 3808 forming a part of the projection device 3601 and other driving circuits.

FIG. 23B shows a rear type projector, which includes a main body 3701, a projection device 3702, and a mirror 370.
3, including a screen 3704 and the like. The present invention relates to a projection device 2
The present invention can be applied to a liquid crystal display device 3808 which constitutes a part of the LCD 702 and other driving circuits.

FIG. 23C is a diagram showing an example of the structure of the projection devices 3601 and 3702 in FIGS. 23A and 23B. Projection devices 3601, 37
02 denotes a light source optical system 3801, mirrors 3802, 380
4 to 3806, dichroic mirror 3803, prism 3807, liquid crystal display device 3808, retardation plate 380
9. It is composed of a projection optical system 3810. Projection optical system 28
Reference numeral 10 denotes an optical system including a projection lens. In this 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. Further, 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 the optical path indicated by the arrow in FIG. Good.

FIG. 23D is a view showing an example of the structure of the light source optical system 3801 in FIG. 23C. In this embodiment, the light source optical system 3801 includes a reflector 2811, a light source 3812, a lens array 3813,
814, a polarization conversion element 2815, and a condenser lens 3816. Note that the light source optical system shown in FIG. 23D 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. 23, a case where a transmissive electro-optical device is used is shown, and an example of application to a reflective electro-optical device and a light emitting device is not shown.

FIG. 24A shows a portable telephone, and a main body 39.
01, audio output unit 3902, audio input unit 3903, display unit 3904, operation switch 3905, antenna 3906
And so on. The present invention can be applied to the display portion 3904.

FIG. 24B shows a portable book (electronic book), which includes a main body 4001, display portions 4002 and 4003, a storage medium 4004, operation switches 4005, and an antenna 4006.
And so on. The present invention can be applied to the display portions 4002 and 4003.

FIG. 24C shows a display, which includes a main body 4101, a support 4102, a display portion 4103, and the like.
The present invention can be applied to the display portion 4103. 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.

[0157]

According to the present invention, by irradiating a semiconductor film with a laser beam on which interference fringes are intentionally formed, a plurality of rows of crystal grains are formed by lateral growth, and the moving distance of the laser beam is reduced by mp Throughput is improved by ± w (m is a natural number, p is a pitch of a periodic energy distribution in laser light, w is a width of a crystal grain to be formed), or a beam width or a beam length of the laser light. Then, it becomes possible to obtain a crystalline semiconductor film in which the entire surface of the semiconductor film is filled with crystal grains formed by lateral growth. Further, if the shape of the laser beam on the irradiation surface or in the vicinity thereof is linear, the throughput can be further improved.

Further, in the embodiments, the laser light having a linear or rectangular shape on the irradiation surface has been described, but the present invention can be applied to laser light having other shapes.

[Brief description of the drawings]

FIG. 1 is a diagram showing the concept of the present invention.

FIG. 2 is a view showing an irradiation method of the present invention and a crystalline semiconductor film obtained.

FIG. 3 is a diagram showing an example of a configuration of a laser irradiation apparatus according to the present invention.

FIG. 4 is a graph showing absorption coefficients of an amorphous silicon film and a crystalline silicon film with respect to wavelength.

FIG. 5 is a diagram showing a state of crystal grains obtained by a conventional laser beam.

FIG. 6 is a diagram showing a conventional irradiation method and a crystalline semiconductor film obtained.

FIG. 7 is a diagram for obtaining an incident angle of a laser beam for overall lateral growth.

FIG. 8 is a diagram showing an example of a configuration of a laser irradiation apparatus according to the present invention.

FIG. 9 is a diagram showing an example of a configuration of a laser irradiation apparatus according to the present invention.

FIG. 10 is a diagram showing an intensity distribution of laser light and crystal grains formed on an irradiation surface by the optical system of FIG. 9;

FIG. 11 illustrates a crystalline semiconductor film formed by a laser irradiation method of the present invention.

FIG. 12 is a schematic diagram of FIG. 11;

FIG. 13 is a diagram showing an example of the configuration of a laser irradiation apparatus according to the present invention.

FIG. 14 is a cross-sectional view illustrating an example of a manufacturing process of a pixel TFT and a TFT of a driver circuit.

FIG. 15 is a cross-sectional view illustrating an example of a manufacturing process of a pixel TFT and a TFT of a driver circuit.

FIG. 16 is a cross-sectional view illustrating an example of a manufacturing process of a pixel TFT and a TFT of a driver circuit.

FIG. 17 is a cross-sectional view illustrating an example of a manufacturing process of a pixel TFT and a TFT of a driver circuit.

FIG. 18 is a top view illustrating pixels in a pixel portion.

FIG. 19 is a cross-sectional view illustrating a manufacturing process of an active matrix liquid crystal display device.

FIG. 20 is a cross-sectional structural view of a driving circuit and a pixel portion of a light-emitting device.

FIG. 21A is a top view of a light-emitting device. FIG. 2B is a cross-sectional structural view of a driving circuit and a pixel portion of a light-emitting device.

FIG. 22 illustrates an example of a semiconductor device.

FIG 23 illustrates an example of a semiconductor device.

FIG 24 illustrates an example of a semiconductor device.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 21/336 F-term (Reference) 2H092 GA59 JA25 JA29 JA38 JA42 JB13 JB23 JB32 JB54 JB57 JB63 JB69 KA04 MA08 MA12 MA27 MA30 MA35 MA37 NA24 RA05 5C094 AA07 AA13 AA25 AA43 AA48 AA53 BA03 BA27 BA43 CA19 DA09 DA13 EA04 EA05 EA10 EB02 FA01 FA02 FB12 FB14 FB15 GB10 5F052 AA02 BA04 BA07 BA14 BB02 BB05 BB07 DD02 DD03 DD01 DD02 DD01 DD15 DD17 EE01 EE02 EE03 EE04 EE06 EE09 EE14 EE23 EE28 EE44 EE45 FF02 FF04 FF28 FF30 FF36 PP GG01 GG02 GG13 GG25 GG32 GG43 GG45 NN04 NN03 NN03 HL03 NN03 HL02 HL03 HL02 HL03 HL02 HL03 PP05 PP06 PP23 PP34 PP35 PP40 QQ11 QQ23 QQ25

Claims (31)

[Claims] 1. A method for manufacturing a semiconductor device, comprising a step of irradiating a semiconductor film with laser light having a periodic energy distribution in one direction on or near an irradiation surface. And a step of irradiating the semiconductor film with laser light having a periodic energy distribution in one direction on or near the irradiation surface, wherein the laser light is directed relative to the semiconductor film in the one direction. A method for manufacturing a semiconductor device, characterized in that irradiation is performed while moving the semiconductor device. 3. A step of irradiating the semiconductor film with laser light having a periodic energy distribution in one direction on or near the irradiation surface, wherein the laser light is emitted relative to the semiconductor film in the one direction. The laser beam is irradiated while being moved, and the relative movement distance of the laser beam with respect to the semiconductor film for each pulse is determined by the width w of a row of crystal grains formed by the laser beam irradiation and the periodic energy distribution. Wherein the pitch p and the natural number m are mp ± w. 4. A step of dividing a first laser beam into a plurality of second laser beams, and synthesizing the plurality of second laser beams to form a periodic energy in one direction on or near an irradiation surface. Forming a third laser beam having a distribution, irradiating the semiconductor film with the third laser beam,
The incident angle θ of the second laser light is the wavelength λ of the second laser light, the width w of the row of crystal grains formed by the irradiation of the third laser light, When the pitch of the energy distribution is p, sin θ = λ / p (where p
= 2w). 5. A step of dividing a first laser beam into a plurality of second laser beams, and synthesizing the plurality of second laser beams to form a periodic energy in one direction at or near an irradiation surface. Forming a third laser beam having a distribution, irradiating the semiconductor film with the third laser beam,
And the third laser light is directed to the semiconductor film.
Irradiation is performed while relatively moving in the one direction, the incident angle θ of the second laser light is the wavelength λ of the second laser light,
When the width w of the row of crystal grains formed by the irradiation of the third laser beam and the pitch p of the periodic energy distribution are satisfied, sin θ = λ / p (where p = 2w) is satisfied. Of manufacturing a semiconductor device. 6. A method for manufacturing a semiconductor device, comprising a step of irradiating a semiconductor film with a rectangular beam having a periodic energy distribution in a short axis direction on or near an irradiation surface. 7. A step of irradiating the semiconductor film with a rectangular beam having a periodic energy distribution in a short axis direction at or near an irradiation surface, wherein the rectangular beam is applied to the semiconductor film by the short beam. A method for manufacturing a semiconductor device, wherein irradiation is performed while relatively moving in an axial direction. 8. A step of irradiating the semiconductor film with a rectangular beam having a periodic energy distribution in the minor axis direction on or near the irradiation surface, wherein the rectangular beam is applied to the semiconductor film by Irradiation is performed while relatively moving in the axial direction, and the relative movement distance of the rectangular beam with respect to the semiconductor film for each pulse is a width w of a row of crystal grains formed by the irradiation of the rectangular beam, When the pitch p of the periodic energy distribution is a natural number m, mp ± w
A method for manufacturing a semiconductor device. 9. A step of dividing the first laser beam into a plurality of second laser beams, and synthesizing the plurality of second laser beams to form a periodic beam in the minor axis direction on or near the irradiation surface. Forming a rectangular beam having an energy distribution, and irradiating the semiconductor film with the rectangular beam, wherein an incident angle θ of the rectangular beam is a wavelength λ of the second laser light, When the width w of the row of crystal grains formed by the irradiation of the rectangular beam and the pitch p of the periodic energy distribution are sin θ = λ / p (where p = 2
a method for manufacturing a semiconductor device, which satisfies w). 10. A step of dividing a first laser beam into a plurality of second laser beams, and synthesizing the plurality of second laser beams to form a periodic beam in a short axis direction on or near an irradiation surface. Forming a rectangular beam having an energy distribution, and irradiating the semiconductor film with the rectangular beam, wherein the rectangular beam is relative to the semiconductor film in the minor axis direction. Irradiation while moving, the incident angle θ of the rectangular beam is the wavelength λ of the second laser beam, the width w of a row of crystal grains formed by the irradiation of the rectangular beam, and the periodic energy distribution. A method of manufacturing a semiconductor device, wherein sin θ = λ / p (where p = 2w) is satisfied when the pitch is p. 11. A method for manufacturing a semiconductor device, comprising a step of irradiating a semiconductor film with a rectangular beam having a periodic energy distribution in a major axis direction at or near an irradiation surface. 12. A method of irradiating a semiconductor film with a rectangular beam having a periodic energy distribution in a major axis direction on or near an irradiation surface, wherein the rectangular beam is applied to the semiconductor film by the long beam. A method for manufacturing a semiconductor device, wherein irradiation is performed while relatively moving in an axial direction. 13. A method of irradiating a semiconductor film with a rectangular beam having a periodic energy distribution in a major axis direction on or near an irradiation surface, wherein the rectangular beam is applied to the semiconductor film by the long beam. Irradiation is performed while relatively moving in the axial direction, and the relative movement distance of the rectangular beam with respect to the semiconductor film for each pulse is a width w of a row of crystal grains formed by the irradiation of the rectangular beam, When the pitch p of the periodic energy distribution is a natural number m, mp ±
w, a method for manufacturing a semiconductor device. 14. A step of dividing a first laser beam into a plurality of second laser beams, and synthesizing the plurality of second laser beams to form a plurality of second laser beams periodically in a major axis direction at or near an irradiation surface. Forming a rectangular beam having an energy distribution, and irradiating the semiconductor film with the rectangular beam, wherein an incident angle θ of the rectangular beam is a wavelength λ of the second laser light, When the width w of the row of crystal grains formed by the irradiation of the rectangular beam and the pitch p of the periodic energy distribution are sin θ = λ / p (where p = 2
a method for manufacturing a semiconductor device, which satisfies w). 15. A step of dividing a first laser beam into a plurality of second laser beams, and synthesizing the plurality of second laser beams to form a plurality of second laser beams periodically in a major axis direction on or near an irradiation surface. Forming a rectangular beam having an energy distribution, and irradiating the semiconductor film with the rectangular beam, wherein the rectangular beam is relative to the semiconductor film in the major axis direction. Irradiation while moving, the incident angle θ of the rectangular beam is the wavelength λ of the second laser beam, the width w of a row of crystal grains formed by the irradiation of the rectangular beam, and the periodic energy distribution. A method of manufacturing a semiconductor device, wherein sin θ = λ / p (where p = 2w) is satisfied when the pitch is p. 16. The periodic energy distribution in the laser light according to claim 1, wherein:
A method for manufacturing a semiconductor device, wherein laser light emitted from a laser oscillator is formed by interference with an optical system. 17. The periodic energy distribution in the third laser light according to claim 4 or 5,
A method for manufacturing a semiconductor device, wherein a plurality of the second laser beams are formed by interference by an optical system. 18. The periodic energy distribution in the rectangular beam according to any one of claims 6 to 8 and 11 to 13, wherein a laser beam emitted from a laser oscillator interferes with an optical system. A method for manufacturing a semiconductor device, which is formed. 19. The periodic energy distribution in the rectangular beam according to claim 9, 10, 10, 14, or 15, wherein the plurality of second laser beams interfere with each other by an optical system. A method for manufacturing a semiconductor device. 20. The optical device according to claim 16, wherein the optical system is a cylindrical array lens,
Alternatively, a method for manufacturing a semiconductor device including a cylindrical lens, or both a cylindrical array lens and a cylindrical lens. 21. The method for manufacturing a semiconductor device according to claim 16, wherein the optical system includes a half mirror. 22. The method for manufacturing a semiconductor device according to claim 16, wherein the optical system includes a mirror. 23. The method for manufacturing a semiconductor device according to claim 16, wherein the optical system includes a slit. 24. The laser device according to claim 1, wherein the laser beam is an Nd: YAG laser, and Nd: YL.
F laser, Nd: YVO ₄ laser, or Nd: YA
A method for manufacturing a semiconductor device, which is laser light oscillated from one kind selected from an IO ₃ laser. 25. The method according to claim 4, wherein the first laser beam is an Nd: YAG laser,
d: YLF laser, Nd: YVO ₄ laser, or N
d: A method for manufacturing a semiconductor device, which is a laser beam oscillated from a type selected from YAlO ₃ lasers. 26. The method for manufacturing a semiconductor device according to claim 1, wherein a wavelength of the laser light is in a range of 370 to 650 nm. 27. The method for manufacturing a semiconductor device according to claim 4, wherein a wavelength of the laser light is in a range of 370 to 650 nm. 28. The method for manufacturing a semiconductor device according to claim 6, wherein a wavelength of the rectangular beam is in a range of 370 to 650 nm. 29. The method for manufacturing a semiconductor device according to claim 1, wherein the semiconductor film is a film containing silicon. 30. The method for manufacturing a semiconductor device according to claim 1, wherein the semiconductor device is a liquid crystal display device or a light emitting device. 31. The semiconductor device according to claim 1, wherein the semiconductor device is a mobile phone, a video camera, a digital camera, a projector, a goggle type display, a personal computer, a DVD player, an electronic book, or portable information. A method for manufacturing a semiconductor device, which is a terminal.