JP5311754B2 - Crystalline semiconductor film, semiconductor device and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor film capable of reducing variation of electric characteristics among semiconductor elements, and to provide a semiconductor device provided with the same and manufacturing methods of theses. <P>SOLUTION: In the manufacturing method, an insulating film is formed on a substrate, an amorphous semiconductor film is formed on the insulating film, a silicon nitride film having a film thickness of 200-1,000 nm containing not more than 10 atomic% oxygen and having a composition rate of 1.3-1.5 of the nitride to the silicon is formed on the amorphous semiconductor film, the amorphous semiconductor film is irradiated with a continuously oscillating laser beam transmitting the silicon nitride film and a laser beam having a repetitive frequency of 10 MHz or more to melt the amorphous semiconductor film and crystallize it to form a crystalline semiconductor film, and a semiconductor film is formed by using the crystalline semiconductor film. This method can form a crystalline semiconductor film in which plane orientation of crystals are prepared at a predetermined proportion or more on three orthogonal planes. As a result, the variation of electric characteristics among adjacent semiconductor elements can be reduced, and a semiconductor device having excellent characteristics can be obtained. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

The present invention relates to a semiconductor film having a crystal structure formed by using a laser crystallization technique, a semiconductor device such as a thin film transistor (hereinafter referred to as TFT) including the semiconductor film, and a manufacturing method thereof.
More specifically, the present invention has a specific crystal structure formed by using a laser crystallization technique, that is, variations in electrical characteristics between semiconductor elements in which the plane orientations of three orthogonal crystals are more than a certain ratio. The present invention relates to a semiconductor film with reduced resistance, a semiconductor device including the same, and a manufacturing method thereof.

In recent years, laser crystallization technology for forming a semiconductor film having a crystal structure (hereinafter referred to as a crystalline semiconductor film) by irradiating an amorphous semiconductor film formed on a glass substrate with a laser beam has been widely studied. Proposals have been made.
The crystalline semiconductor film is used because it has a higher mobility than an amorphous semiconductor film. As a result, this crystalline semiconductor film uses this to form a TFT. It is used for an active matrix type liquid crystal display device or an organic EL display device in which TFTs for a pixel portion or for a pixel portion and a drive circuit are formed on a single glass substrate.

In addition to the laser crystallization, the crystallization method includes a thermal annealing method using a furnace annealing furnace and an instantaneous thermal annealing method (RTA method). When the laser crystallization is used, the temperature of the substrate is increased. Therefore, it is possible to crystallize by absorbing heat only in the semiconductor film without increasing the temperature so much that a substance having a low melting point such as glass or plastic can be used for the substrate.
As a result, it becomes possible to use a glass substrate that is inexpensive and easy to process in a large area, and laser crystallization can significantly improve production efficiency and is an excellent crystallization technique.

The present applicant pays attention to the excellent characteristics of the crystallization method, and has sought to manufacture a semiconductor film by laser crystallization, and as a result, has succeeded in developing many techniques.
Among its successful technologies, semiconductor characteristics, especially high mobility crystals, are obtained by irradiating an amorphous film with reduced oxygen, nitrogen, and carbon concentrations with a laser beam, followed by a melting process and a recrystallization process. There is a technique for obtaining a conductive semiconductor film (Patent Document 1), and the proposal of the technique also discloses that it is preferable to form a protective film on an amorphous film at the time of laser irradiation. It is also disclosed that impurities can be avoided in the silicon film by providing a protective film.
Japanese Patent Laid-Open No. 5-299339

  The applicant was not satisfied with the development of the crystallization technology, and continued research and development to produce a crystalline semiconductor film with better characteristics, and ultimately a single crystal semiconductor film from a non-single crystal semiconductor film. As a result, the present inventor has found that a crystalline semiconductor film having a specific crystal structure can be manufactured from a non-single crystal semiconductor film, and the semiconductor film has crystal planes in three orthogonal planes. It was found that the orientation was aligned at a certain rate or more.

As described above, the present inventors have succeeded in developing a crystalline semiconductor film having a specific crystal structure and a manufacturing method thereof.
In addition, it has also been successfully used to develop a semiconductor device including the crystalline semiconductor film and a manufacturing method thereof.
Therefore, the present invention provides a semiconductor film having a specific crystal structure close to a single crystal structure and a manufacturing method thereof, and includes the semiconductor film, so that the electrical characteristics are the same as when a single crystal semiconductor substrate is used. SUMMARY OF THE INVENTION It is an object of the present invention to provide a semiconductor device and a manufacturing method thereof that are excellent and have reduced variation in electrical characteristics between semiconductor elements.

As described above, the present invention provides a crystalline semiconductor film, a semiconductor device, and a manufacturing method thereof, and the crystalline semiconductor film and the semiconductor device have two aspects.
A first aspect of the crystalline semiconductor film is a semiconductor film composed of a plurality of crystal grains on a substrate, and the crystal plane orientation is an angle of ± 10 ° on the first surface of the semiconductor film. Within the range of fluctuation, the <001> orientation is 60% or more and less than 100%, and on the second surface of the semiconductor film, the crystal plane orientation is <001>, <101>,<201>,<301>,<401>,<501> or <601> has an orientation of 60% or more and less than 100%, and the third plane of the semiconductor film has a crystal plane. As for the azimuth, any one of <001>, <101>, <201>, <301>, <401>, <501>, or <601> within a range of ± 10 ° angle fluctuation is 60% or more. And the first surface of the semiconductor film is formed on the substrate. The direction perpendicular to the plane is the first direction, the first direction is a plane that is a normal vector, the second plane of the semiconductor film is parallel to the surface of the substrate, and the crystal growth direction of the crystal grains The second direction is a plane in which the second direction is a normal vector, the third plane of the semiconductor film is parallel to the surface of the substrate, and crystal growth of crystal grains A direction perpendicular to the direction is a third direction, and the third direction is a plane that is a normal vector.

  A second aspect of the crystalline semiconductor film is a semiconductor film composed of a plurality of crystal grains on a substrate, and the crystal plane orientation is an angle of ± 10 ° on the first surface of the semiconductor film. Within the range of fluctuation, the <001> orientation is 60% or more and less than 100%, and on the second surface of the semiconductor film, the crystal plane orientation is <x01> (x = 0, 1, 2, 3, 4, 5, 6) is 60% or more and less than 100%, and in the third plane of the semiconductor film, the crystal plane orientation has an angular fluctuation of ± 10 °. Within the range, the orientation of <x01> (x = 0, 1, 2, 3, 4, 5, 6) is 60% or more and less than 100%, and the first surface of the semiconductor film is on the surface of the substrate. A vertical direction is a first direction, the first direction is a surface that is a normal vector, and the second surface of the semiconductor film is: A direction parallel to the surface of the plate and parallel to the crystal growth direction of the crystal grains is a second direction, the second direction is a normal vector, and the third surface of the semiconductor film is The third direction is a direction parallel to the surface of the substrate and perpendicular to the crystal growth direction of the crystal grains, and the third direction is a plane that is a normal vector.

  According to a first aspect of the semiconductor device, there is provided a semiconductor device having a semiconductor element including a semiconductor film formed of a plurality of crystal grains on a substrate, the first surface of the semiconductor film being a crystal plane. The orientation of the <001> orientation is 60% or more and less than 100% within the range of ± 10 ° angular fluctuation, and the crystal plane orientation of the semiconductor film on the second surface of the semiconductor film is ± 10 ° angular fluctuation. Within the range, any orientation of <001>, <101>, <201>, <301>, <401>, <501> or <601> is 60% or more and less than 100%, In plane 3, the crystal plane orientation is <001>, <101>, <201>, <301>, <401>, <501> or <601> within the range of ± 10 ° angular fluctuation. Direction is 60% or more and less than 100% And the first surface of the semiconductor film is a surface in which a direction perpendicular to the surface of the substrate is a first direction and the first direction is a normal vector, and the second surface of the semiconductor film is A direction parallel to the surface of the substrate and parallel to the crystal growth direction of the crystal grains is a second direction, and the second direction is a normal vector, and the third surface of the semiconductor film is The third direction is a direction parallel to the surface of the substrate and perpendicular to the crystal growth direction of the crystal grains, and the third direction is a plane that is a normal vector.

  A second aspect of the semiconductor device is a semiconductor device having a semiconductor element including a semiconductor film made up of a plurality of crystal grains on a substrate, wherein the crystal plane orientation is in the first surface of the semiconductor film. In the range of ± 10 ° angle fluctuation, the <001> orientation is 60% or more and less than 100%, and in the second face of the semiconductor film, the crystal plane orientation is within the range of ± 10 ° angle fluctuation. The orientation of <x01> (x = 0, 1, 2, 3, 4, 5, 6) is 60% or more and less than 100%, and in the third plane of the semiconductor film, the crystal plane orientation is ± Within the range of 10 ° angle fluctuation, the orientation of <x01> (x = 0, 1, 2, 3, 4, 5, 6) is 60% or more and less than 100%, and the first surface of the semiconductor film is A direction perpendicular to the surface of the substrate is a first direction, and the first direction is a normal vector. The second surface of the semiconductor film is parallel to the surface of the substrate and the direction parallel to the crystal growth direction of the crystal grains is a second direction, and the second direction is a normal vector. The third surface of the semiconductor film is parallel to the surface of the substrate and a direction perpendicular to the crystal growth direction of the crystal grains is a third direction, and the third direction is a normal vector. It is the surface which becomes.

Furthermore, in the semiconductor film and the semiconductor device, the following is preferable in each first aspect.
(1) In the first plane of the semiconductor film, the crystal plane orientation is within the range of ± 10 ° angular fluctuation, and the <001> orientation is 70% or more and less than 100%,
In the second plane of the semiconductor film, the crystal plane orientation is 70% or more of any of <301>, <401>, <501>, or <601> within a range of ± 10 ° angular fluctuation. Less than 100%,
In the third plane of the semiconductor film, the crystal plane orientation is 70% or more of any of <301>, <401>, <501>, or <601> within a range of ± 10 ° angular fluctuation. Be less than 100%,
(2) The crystal grains of the semiconductor film have a width of 0.1 to 10 μm and a length of 5 to 50 μm.
(3) The semiconductor is Si, Si _1-x Ge _x (0 <x <0.1),
(4) The semiconductor element is a thin film transistor, a diode, a resistor element, a capacitor element, a CCD, or a photoelectric conversion element (only applicable to a semiconductor device).

The plane orientation of the crystal in the present invention will be described below with specific examples.
For example, the plane orientation <001> is a group of equivalent orientations such as [100], [010], [001], and a plane orientation in which each of the plane orientations is −1. It is written.
Further, regarding the plane orientation <301>, [310], [301], [130], [103], [013], [031], and one or both of 1 and 3 in each of the plane orientations are Equivalent azimuth groups such as negative surface orientations are collectively shown as <301>.

The meaning of the crystal plane orientation <x01> (x = 0, 1, 2, 3, 4, 5, 6) is as follows.
The above-mentioned plane orientation <x01> indicates the sum of orientation ratios of plane orientations <001>, <601>, <501>, <401>, <301>, <201>, and <101>.
In this case, when the plane orientations <001> to <601> are simply summed up, there is an overlapping portion in a part of each plane orientation, so that each plane orientation of the plane orientations <001> to <601>. For the overlapping portion, the result calculated as only the orientation ratio in one of the plane orientations was defined as the plane orientation <x01>.

Furthermore, the above-mentioned “within ± 10 ° angular fluctuation range” indicates that the deviation from a certain plane orientation is in the range from −10 ° to + 10 °.
That is, it means that a certain plane orientation allows a range of ± 10 ° as the range of the fluctuation angle.
For example, within the range of ± 10 ° angular fluctuation, the <001> orientation refers to a crystal having a plane orientation <001> from a crystal having a deviation of −10 ° to a crystal having a deviation of + 10 ° from the plane orientation <001>. It is meant to include.

And the manufacturing method of a crystalline semiconductor film forms an insulating film on a substrate,
An amorphous semiconductor film is formed over the insulating film, the thickness of the amorphous semiconductor film is 200 to 1000 nm, oxygen is 10 atomic% or less, and the composition ratio of nitrogen to silicon is 1.3 or more and 1 The amorphous semiconductor film is formed by forming a silicon nitride film having a thickness of .5 or less and irradiating the amorphous semiconductor film with a continuous wave laser beam or a laser beam having a repetition frequency of 10 MHz or more that is transmitted through the silicon nitride film. It is characterized by crystallization after melting.

In addition, a method for manufacturing a semiconductor device includes forming an insulating film over a substrate,
An amorphous semiconductor film is formed over the insulating film, the thickness of the amorphous semiconductor film is 200 to 1000 nm, oxygen is 10 atomic% or less, and the composition ratio of nitrogen to silicon is 1.3 or more and 1 The amorphous semiconductor film is formed by forming a silicon nitride film having a thickness of .5 or less and irradiating the amorphous semiconductor film with a continuous wave laser beam or a laser beam having a repetition frequency of 10 MHz or more that is transmitted through the silicon nitride film. Then, it is crystallized to form a crystalline semiconductor film, and a semiconductor element is formed using the crystalline semiconductor film.

Further, in the production method thereof, the following is preferable.
(1) The silicon nitride containing oxygen is formed by a plasma CVD method in an atmosphere containing SiH ₄ , NH ₃ and N ₂ O, or in an SiH ₄ and NH ₃ atmosphere.
(2) The film thickness of the amorphous semiconductor film is 20 to 80 nm,
(3) The continuous wave laser beam or the laser beam having a repetition frequency of 10 MHz or more has a wavelength that is absorbed by the amorphous semiconductor film.

The crystalline semiconductor film of the present invention has a specific crystal structure, that is, crystal plane orientations in three orthogonal planes are uniform, and thereby excellent semiconductor characteristics can be exhibited.
Specifically, according to the first aspect, in the first plane of the semiconductor film, the crystal plane orientation is such that the <001> orientation is 60% or more and less than 100% within an angular fluctuation range of ± 10 °. , Preferably 70% or more and less than 100%,
In the second surface of the semiconductor film, the crystal plane orientation is 60% or more of any of <301>, <401>, <501>, or <601> within a range of ± 10 ° angular fluctuation. Less than 100%, preferably more than 70% and less than 100%,
In the third plane of the semiconductor film, the crystal plane orientation is 60% or more of any of <301>, <401>, <501>, or <601> within a range of ± 10 ° angular fluctuation. Less than 100%, preferably more than 70% and less than 100%,
The first surface of the semiconductor film is a surface in which a direction perpendicular to the surface of the substrate is a first direction, and the first direction is a normal vector,
The second surface of the semiconductor film is a surface parallel to the surface of the substrate and a direction parallel to the crystal growth direction of the crystal grains as a second direction, and the second direction is a normal vector. ,
The third surface of the semiconductor film is a surface that is parallel to the surface of the substrate and is perpendicular to the crystal growth direction of the crystal grains as a third direction, and the third direction is a normal vector. That is.

That is, the crystalline semiconductor film of the present invention has the above-described crystal structure, and the present invention is a thin film transistor (hereinafter referred to as a thin film transistor) having excellent characteristics that variation in electrical characteristics is reduced between adjacent semiconductor elements. , TFT) and the like, and a manufacturing method thereof can be provided.
In this case, a silicon nitride film having an optimized thickness and composition ratio is formed on the amorphous semiconductor film, and the continuous wave laser beam or the light transmitted through the silicon nitride film is formed. A crystal whose crystal plane orientation is aligned at a certain ratio or more in three orthogonal planes by irradiating an amorphous semiconductor film with laser light having a repetition frequency of 10 MHz or more, melting the amorphous semiconductor film, and then crystallizing the amorphous semiconductor film. A conductive semiconductor film can be formed.
As a result, it is possible to manufacture a semiconductor device that has excellent electrical characteristics, reduces variation in electrical characteristics between adjacent semiconductor elements, and has excellent characteristics.
The same applies to the second aspect.

In the following, the present invention will be described in detail with reference to the drawings including the best mode for carrying out the invention. However, the present invention is not limited to the embodiments in any way, and is not limited to patents. Needless to say, it is specified by the description of the scope of claims.

[Embodiment 1]
In the first embodiment, first, the outline of the manufacturing process of the crystalline semiconductor film of the present invention will be described with reference to FIG. 1 and FIG. 18, and then the basic matters concerning the crystal structure, the crystalline semiconductor film of the present invention, The crystal structure will be specifically described with reference to FIGS.
However, the present invention can be implemented in many different forms, and it is easy for those skilled in the art to change various aspects and details without departing from the spirit and scope of the present invention. To be understood.
Therefore, as described above, the present invention is not construed as being limited to the description of the embodiment.

First, as illustrated in FIG. 1, for example, a glass substrate having a thickness of 0.7 mm is used as the substrate 100 having an insulating surface, and nitrogen having a thickness of 50 nm to 150 nm is formed as an insulating film 101 functioning as a base film on one surface thereof. A silicon oxide film containing is formed.
Further, an amorphous semiconductor film with a thickness of 20 nm to 100 nm, preferably 20 nm to 80 nm, is formed as the semiconductor film 102 over the insulating film 101 by a plasma CVD method.

Note that the insulating film 101 functioning as a base film may be provided as necessary. When the substrate 100 is glass, impurities from the glass are prevented from diffusing into the semiconductor film 102. When a quartz substrate is used as 100, it is not necessary to provide the insulating film 101 functioning as a base film.
Alternatively, a separation layer may be provided between the insulating film 101 and the substrate 100, and the semiconductor element may be separated from the substrate 100 after the process is completed.

As for the semiconductor film 102, amorphous silicon is used in this embodiment mode, but polycrystalline silicon may be used, or silicon germanium (Si _1-x Ge _x (0 <x <0.1)). Further, silicon carbide (SiC) whose single crystal has a diamond structure can be used.

Further, after the semiconductor film 102 is formed, it may be heated in an electric furnace at 500 ° C. for 1 hour, and this heat treatment is treatment for extracting hydrogen from the amorphous silicon film.
Note that the hydrogen is emitted in order to prevent hydrogen gas from being ejected from the semiconductor film 102 when the laser beam is irradiated. If the hydrogen contained in the semiconductor film 102 is small, the hydrogen can be omitted.
In this embodiment, an example of amorphous silicon is shown as the semiconductor film 102, but polycrystalline silicon may be used. For example, after the amorphous silicon film is formed, It can be formed by adding a trace amount of elements such as nickel, palladium, germanium, iron, palladium, tin, lead, cobalt, platinum, copper, gold, and then performing a heat treatment at 550 ° C. for 4 hours.

Next, a silicon nitride film containing oxygen at a thickness of 200 nm to 1000 nm and having a composition ratio of nitrogen to silicon of 1.3 to 1.5 is formed as a cap film 103 over the semiconductor film 102. To do.
It should be particularly noted that if the cap film 103 is too thin, it is difficult to control the plane orientation of a crystalline semiconductor film to be formed later. Therefore, it is preferable to form the cap film 103 with a thickness of 200 nm to 1000 nm. .

For this cap film 103, in this embodiment, oxygen of 300 nm thickness is formed by plasma CVD using monosilane (SiH ₄ ), ammonia (NH ₃ ), and nitrous oxide (N ₂ O) as reaction gases. A silicon nitride film is formed.
Nitrous oxide (N ₂ O) is used as an oxidant, and oxygen having an oxidizing action may be used instead.

The cap film 103 preferably has a sufficient transmittance with respect to the wavelength of the laser beam and has a thermal value such as a thermal expansion coefficient or a value such as ductility that is close to that of the adjacent semiconductor film.
Further, the cap film 103 is preferably a hard and dense film equivalent to a gate insulating film of a thin film transistor to be formed later. Such a hard and dense film is formed, for example, by lowering the film formation rate. be able to.
Note that in the case where the cap film contains a large amount of hydrogen, similarly to the semiconductor film 102, heat treatment is performed to extract hydrogen.

Next, a laser oscillator used for crystallization by irradiating an amorphous semiconductor film with a laser and an optical system for forming a beam spot will be described.
As shown in FIG. 18, lasers with wavelengths that are absorbed by the semiconductor film 102 by several tens of percent or more are used as the laser oscillators 11a and 11b.
Typically, the second harmonic or the third harmonic can be used. Here, the total maximum output is 20 W, and the LD excitation (laser diode excitation) continuous wave laser (YVO ₄ , second harmonic) (Wavelength 532 nm)).
The second harmonic is not particularly limited to the second harmonic, but the second harmonic is superior to higher harmonics in terms of energy efficiency.

The laser power used in the present invention is within a range in which the semiconductor film can be completely melted and a crystalline semiconductor film having a uniform crystal plane orientation can be formed.
If a laser power lower than this range is used, the semiconductor film cannot be completely melted, the crystal plane orientation is not aligned in a certain direction, and a crystalline semiconductor film with small crystal grains is formed. Accordingly, in the case of FIG. 18, two laser oscillators are prepared, but one may be used if the output is sufficient.
On the other hand, if a laser power higher than this range is used, a large amount of crystal nuclei are generated in the semiconductor film and disordered crystal growth occurs from the crystal nuclei, so that the position, size, and plane orientation of the crystal grains are unsatisfactory. A uniform crystalline semiconductor film is formed.

When the semiconductor film 102 is irradiated with the continuous wave laser, energy is continuously given to the semiconductor film 102. Therefore, once the semiconductor film is brought into a molten state, the state can be continued.
Further, the solid-liquid interface of the semiconductor film can be moved by scanning with a continuous wave laser, and crystal grains that are long in one direction can be formed along the direction of this movement.
The solid laser is used at that time because the output stability is higher than that of a gas laser or the like and stable processing is expected.
Note that not only a continuous wave laser but also a pulse laser having a repetition frequency of 10 MHz or more can be used.

  In this case, if a pulse laser having a high repetition frequency is used, the semiconductor film can always be kept in a molten state in the entire film thickness direction if the pulse interval of the laser is shorter than the time from the melting of the semiconductor film to solidification. In addition, a semiconductor film composed of long crystal grains laterally grown in one direction by the movement of the solid-liquid interface can be formed.

In this embodiment, the YVO ₄ laser is used for the laser oscillators 11a and 11b. However, other continuous oscillation lasers or pulse lasers with a repetition frequency of 10 MHz or more can be used instead.
For example, examples of the gas laser include an Ar laser, a Kr laser, and a CO ₂ laser.
Examples of the solid-state laser include a YAG laser, a YLF laser, a YAlO ₃ laser, a GdVO ₄ laser, a KGW laser, a KYW laser, an alexandrite laser, a Ti: sapphire laser, a Y ₂ O ₃ laser, and a YVO ₄ laser.
Further, there are ceramic lasers such as a YAG laser, a Y ₂ O ₃ laser, a GdVO ₄ laser, and a YVO ₄ laser, and examples of the metal vapor laser include a helium cadmium laser.

The laser oscillators 11a and 11b can emit a laser beam by oscillating in TEM ₀₀ (single transverse mode). In this way, the energy uniformity of the linear beam spot obtained on the irradiated surface can be improved. Since it can raise, it is preferable.

The outline of the optical processing of the laser emitted using these laser oscillators is as follows.
Laser beams 12a and 12b are respectively emitted from the laser oscillators 11a and 11b with the same energy.
The laser beam 12b emitted from the laser oscillator 11b changes the polarization direction through the wave plate 13, because the polarizer 14 combines two laser beams having different polarization directions.

After passing the laser beam 12 b through the wave plate 13, the laser beam 12 b is reflected by the mirror 22, the laser beam 12 b is incident on the polarizer 14, and the laser beam 12 a and the laser beam 12 b are synthesized by the polarizer 14. To do.
At that time, the wavelength plate 13 and the polarizer 14 are adjusted so that light transmitted through the wavelength plate 13 and the polarizer 14 has appropriate energy.
In the present embodiment, the polarizer 14 is used for combining the laser beams, but other optical elements such as a polarizing beam splitter may be used.

The laser beam 12 synthesized by the polarizer 14 is reflected by a mirror 15 and irradiated with a cross-sectional shape of the laser beam by a cylindrical lens 16 having a focal length of, for example, 150 mm and a cylindrical lens 17 having a focal length of, for example, 20 mm. The surface 18 is shaped into a line.
The mirror 15 may be provided according to the installation status of the optical system of the laser irradiation apparatus.

In that case, the cylindrical lens 16 acts in the length direction of the beam spot formed on the irradiated surface 18, and the cylindrical lens 17 acts in the width direction thereof. For example, a linear beam spot having a length of about 500 μm and a width of about 20 μm is formed.
In this embodiment, a cylindrical lens is used to form a linear shape. However, the present invention is not limited to this, and other optical elements such as a spherical lens may be used. The focal length of the cylindrical lens is Not limited to the above values, it can be set freely.

Further, in this embodiment, the laser beam is shaped using the cylindrical lenses 16 and 17, but an optical system for extending the laser beam in a linear shape and a thin light beam for focusing on the irradiated surface. An optical system may be provided separately.
For example, a cylindrical lens array, a diffractive optical element, an optical waveguide, or the like can be used to make the cross section of the laser beam linear, and if the laser medium has a rectangular shape, the laser beam is emitted at the emission stage. It is also possible to make the cross-sectional shape linear.

In the present invention, a ceramic laser can be used as described above, and when it is used, the shape of the laser medium can be shaped relatively freely. Is suitable.
Note that the cross-sectional shape of the laser beam formed in a linear shape is preferably as narrow as possible. This increases the energy density of the laser beam in the semiconductor film, so that the process time can be shortened.

Next, a laser beam irradiation method will be described.
The irradiated surface 18 on which the semiconductor film 102 covered with the cap film 103 is formed is fixed to the suction stage 19 in order to operate at a relatively high speed.
The suction stage 19 can be moved in the XY direction on the surface parallel to the irradiated surface 18 by the uniaxial robot 20 for the X axis and the uniaxial robot 21 for the Y axis, and the length direction of the linear beam spot and the Y axis Place them so that they match.

Subsequently, the irradiated surface 18 is operated along the width direction of the beam spot, that is, along the X axis, and the irradiated surface 18 is irradiated with the laser beam.
Here, the scanning speed of the X-axis uniaxial robot 20 is 35 cm / sec, and lasers are emitted from the two laser oscillators with an energy of 7.0 W, respectively, and the combined laser output is 14 W.
By irradiation with the laser beam, a region where the semiconductor is completely melted is formed, and a crystal grows in one plane orientation in the process of solidification, so that the crystalline semiconductor film of the present invention can be formed.

The energy distribution of a laser beam emitted from a TEM ₀₀ mode laser oscillator is generally a Gaussian distribution. However, crystal grains whose plane orientations are controlled in three orthogonal planes by an optical system used for laser beam irradiation are as follows. The width of the region to be formed can be changed.
For example, the intensity of the laser beam can be made uniform by using a lens array such as a cylindrical lens array or a fly-eye lens, a diffractive optical element, an optical waveguide, or the like.

By irradiating the semiconductor film 102 with a laser beam with uniform intensity, almost all of the region irradiated with the laser beam can be formed with crystal grains whose plane orientation is controlled in three orthogonal planes.
The scanning speed of the uniaxial robot 20 for the X axis is suitably about several cm / sec to several hundred cm / sec, and an operator may determine it appropriately according to the output of the laser oscillator.

  In this embodiment, a method of moving the semiconductor film 102 that is the irradiated surface 18 using the uniaxial robot 20 for the X axis and the uniaxial robot 21 for the Y axis is used. However, the present invention is not limited to this. The scanning of the laser beam includes an irradiation system moving type in which the irradiated surface 18 is fixed and the irradiation position of the laser beam is moved, an irradiated surface moving type in which the irradiation position of the laser beam is fixed and the irradiated surface 18 is moved, Alternatively, a method combining the above two methods can also be used.

Furthermore, as described above, since the energy distribution in the major axis direction of the beam spot formed by the optical system described above is a Gaussian distribution, small grain crystals are formed at locations where the energy density is low at both ends.
Therefore, a slit or the like is provided in front of the irradiated surface 18 so as to irradiate the irradiated surface 18 only with energy sufficient to form a crystal whose surface orientation is controlled in three orthogonal planes. Or a metal film that reflects a laser beam is formed on the silicon nitride film containing oxygen as the cap film 103, and a crystal whose surface orientation is controlled in three orthogonal planes is to be formed. Only a pattern may be formed so that the laser beam reaches the semiconductor film.

Further, in order to use the laser beams emitted from the laser oscillators 11a and 11b more efficiently, a beam homogenizer such as a lens array or a diffractive optical element is used to uniformly distribute the energy in the length direction of the beam spot. It is good.
Further, it is possible to move the uniaxial robot 21 for the Y axis by the width of the formed crystalline semiconductor film and scan the uniaxial robot 20 for the X axis again at a predetermined speed, here 35 cm / sec. By repeating such a series of operations, the entire surface of the semiconductor film can be efficiently crystallized.

Next, the cap film is removed by etching, and then a resist is applied on the semiconductor film of the crystalline semiconductor film, and the resist is exposed and developed to form a resist in a desired shape.
Further, etching is performed using the resist formed here as a mask, and the crystalline semiconductor film exposed by development is removed.
Through this step, an island-shaped semiconductor film is formed, and a semiconductor device having a semiconductor element such as a thin film transistor, a diode, a resistor, a capacitor, or a CCD can be manufactured using the island-shaped semiconductor film.

Next, the plane orientation of the crystalline semiconductor film manufactured in this embodiment will be described.
In this embodiment mode, an EBSP (Electron Back Scatter Diffraction Pattern: electron backscatter diffraction image) is used for the position and size of crystal grains and the crystal plane orientation of the crystalline semiconductor film from which the cap film has been removed by etching. ) We are measuring, first we will explain the basics of EBSP, then we will explain the results with additional explanations.

  The EBSP refers to diffraction of individual crystals generated when a EBSP detector is connected to a scanning electron microscope (SEM) and a focused electron beam is irradiated to a highly inclined sample in the scanning electron microscope. In this method, the orientation of the image (EBSP image) is analyzed, and the crystal orientation of the sample crystal is measured from the orientation data and position information (x, y) of the measurement point.

When an electron beam is incident on a crystalline semiconductor film, inelastic scattering occurs also in the back, and a linear pattern peculiar to the crystal plane orientation by Bragg diffraction can also be observed in the sample. .
Here, this linear pattern is generally called a Kikuchi line, and the EBSP method obtains the crystal orientation of the crystalline semiconductor film by analyzing the Kikuchi line reflected in the detector. .

In general, a sample having a polycrystalline structure has different plane orientations for each crystal grain.
Therefore, the electron beam is irradiated every time the irradiation position of the crystalline semiconductor film is moved, and the crystal plane orientation is analyzed for each irradiation position.
In this way, the crystal plane orientation and orientation information of the crystalline semiconductor film having a flat surface can be obtained, and the tendency of the plane orientation of the entire crystalline semiconductor film can be obtained as the measurement region is wide. As the number of measurement points increases, information on the crystal plane orientation in the measurement region can be obtained in detail.

However, the plane orientation inside the crystal cannot be determined only by the plane orientation measured from one observation plane of the crystal.
That is because even if the plane orientation is aligned in one direction only on one observation plane, if the plane orientation is not aligned on the other observation plane, it cannot be said that the plane orientation inside the crystal is aligned, Therefore, in order to determine the plane orientation inside the crystal, plane orientations from at least two surfaces are required, and the accuracy increases as the information from more planes increases.

As described above, if the plane orientation distribution is uniform on all three surfaces in the measurement region, it can be regarded as a single crystal approximately.
In practice, as shown in FIG. 2, three planes (observation plane A, observation plane B, and observation plane C) in which three vectors orthogonal to each other (vector a, vector b, and vector c) are normal vectors, respectively. By combining the information, the plane orientation inside the crystal can be specified with high accuracy.

In the crystalline semiconductor film formed in the present embodiment, vectors a to c are set as follows.
Vector c is parallel to the scanning direction of the laser beam (ie, the growth direction of the grains) and the substrate surface, vector a is perpendicular to the substrate surface and vector c, vector b is parallel to the surface of the substrate, and The direction is perpendicular to the crystal growth direction of the crystal grains, that is, perpendicular to the vectors a and c.
From the information from these three observation planes A to C, the plane orientation of the crystal film can be specified with high accuracy.

First, the results of analyzing the plane orientation of the crystalline semiconductor film (the crystal axis orientation in the direction perpendicular to the observation plane) are shown in FIGS.
An electron beam was incident on the surface of the crystalline semiconductor film formed in this embodiment at an incident angle of 60 °, and the crystal plane orientation was measured from the obtained EBSP image.
The measurement range is 50 μm × 50 μm, and in this region, measurement was performed in the form of lattice points every 0.1 μm in length and width.
In addition, since the measurement surface of the EBSP method is the sample surface, the crystalline semiconductor film needs to be the uppermost layer. Therefore, the measurement was performed after etching the silicon nitride film containing oxygen as the cap film.

FIG. 19A shows the distribution of the plane orientation on the observation plane A where the vector a is a normal vector, and FIG. 19B shows the distribution of the plane orientation on the observation plane B where the vector b is a normal vector. FIG. 19C shows a distribution of plane orientations on the observation plane C where the vector c is a normal vector.
19A to 19C are orientation map images showing which plane orientation each measurement point has, and FIG. 19D is a diagram in which each plane orientation of the crystal is color-coded. The plane orientations of the measurement points 19 (a) to 19 (c) are indicated by colors corresponding to the plane orientation of FIG. 19 (d).

Note that FIG. 19 is black and white so that only brightness is difficult to distinguish, but in color display, the observation plane A is strongly oriented in the <001> direction and the observation plane B is strongly oriented in the <301> direction. It can be seen that the observation plane C is strongly oriented in the <301> direction.
In addition, since the inside of each crystal grain has a uniform plane orientation, rough information such as the shape and size of each crystal grain can be grasped by the color and shape.
Further, since the plane orientation <401>, <501>, and <601> are close to the plane orientation <301>, they may be regarded as <301>.

Here, it can be seen from FIGS. 19A to 19C that the crystal grains of the crystalline semiconductor film formed in this embodiment are composed of domains extending in a columnar shape. In (c) to (c), the domain length was 5 to 50 μm, and a domain having a length of 50 μm or more was also observed.
In addition, although the measurement area | region of FIG. 19 is 50 micrometers x 50 micrometers, the domain of length 5-100 micrometers is also seen in a wider range.

Further, from FIGS. 19A to 19C, the crystalline semiconductor film formed in this embodiment has a <001> orientation, a <301> orientation, and a <301> orientation on the observation planes A, B, and C, respectively. It can be seen that they are strongly oriented.
When it is found that the crystal is strongly oriented to a specific index, the degree of orientation can be grasped by obtaining the ratio of how many crystal grains are gathered in the vicinity of the index.

FIGS. 20A to 20C are reverse pole figures showing the frequency distribution of the plane orientations on the observation planes A to C shown in FIG. 19, and FIG. 20D is a scale showing the frequency of the plane orientations. It is.
In FIG. 20, since only the brightness is displayed because it is black and white, it is difficult to discriminate, but the region closer to black shows a higher proportion of crystals having a plane orientation.
From the inverted pole figure shown in FIG. 20 (a), the <001> orientation is closer to black on the observation plane A, specifically, <001 at a frequency of 14.0 times or more of the state in which all orientations appear with equal probability. > It was found that the direction appeared.

Further, from the inverted pole figure shown in FIG. 20B, the <301> orientation is closest to black on the observation plane B, specifically, the frequency is 4.8 times or more the state where all the orientations appear with the same probability. It turns out that <301> orientation appears.
Furthermore, from the inverted pole figure shown in FIG. 20C, the <301> orientation is closest to black on the observation plane C, and more specifically, the frequency is 4.8 times or more the state in which all orientations appear with the same probability. It turns out that <301> orientation appears.

In the reverse pole figures of FIGS. 20 (a) to 20 (c), the orientation rate is obtained for the plane orientation having a high appearance frequency, and the calculation results of the orientation rate are shown in FIGS. 21 (a) to 21 (c).
FIG. 21A shows the result of obtaining the orientation rate on the observation plane A. The orientation rate is determined in the reverse pole figure of FIG. 20A so that the range of <001> orientation angle fluctuation is within ± 10 °. Thus, the angle fluctuation of the <001> azimuth with respect to all the measurement points was obtained by determining the ratio of the number of measurement points existing within ± 10 °.
Note that the colored region in FIG. 21A is a region showing a crystal whose angle fluctuation in the <001> orientation is within ± 10 °.

Further, the value obtained by calculating the ratio of the points having a specific orientation among all the measurement points is the value of the Partition Fraction, and among the points having the specific orientation, the measurement points having high reliability of the orientation with respect to all the measurement points. The value obtained from the orientation ratio is the value of Total Fraction.
From this result, in the observation surface A of the crystalline semiconductor film formed in the first embodiment, the <001> orientation occupies 71.2% within the range of ± 10 ° angular fluctuation.
Regarding the crystal plane orientation, as described above, [100], [010], [001], and equivalent plane orientation groups such as plane orientations in which each of the plane orientations is −1 are collected. It is written as <001>.

FIGS. 21B and 21C show the results of obtaining the orientation ratios on the observation surfaces B and C based on FIGS. 20B and 20C in the same manner as FIG.
21B and 21C is a region showing a crystal having an angle fluctuation of <301> orientation within ± 10 °, and the crystallinity formed in the embodiment. In the observation plane B of the semiconductor film, the <301> orientation occupies 71.1% within an angular fluctuation range of ± 10 °.

In the observation plane C of the crystalline semiconductor film formed in the first embodiment, the <301> orientation occupies 73.9% within the range of ± 10 ° angular fluctuation.
Regarding the crystal plane orientation, as described above, [310], [301], [130], [103], [013], [031], and one or both of 1 and 3 in each of the plane orientations. Equivalent azimuth groups such as plane orientations with negative values are collectively shown as <301>.
Further, in the observation surfaces B and C, the ratio of the plane orientation <301> is shown, but the ratio of the orientation ratio of the plane orientation <401>, <501>, and <601> close to the plane orientation <301> may be used. .

As described above, the crystal orientations of the three observation planes are aligned at a high rate in one direction.
That is, it can be seen that in the crystallized region, an approximately single crystal is formed that can be considered that the plane orientation of the crystal is aligned in one direction.
In this way, it was confirmed that a crystal in which a specific plane orientation occupies a very high ratio is formed on a glass substrate within a region having a side of several tens of μm.

Note that the crystalline semiconductor film manufactured in the present invention is polycrystalline. For this reason, in the orientation ratio of each of the observation planes A to C, if crystal defects such as crystal grain boundaries are included, the orientation ratio of the plane orientation of each observation plane is less than 100%.
The EBSP can be measured, for example, in the channel region of the thin film transistor. That is, measurement is possible with a semiconductor layer covering the gate wiring and the gate insulating film.

From the above results, when the plane orientation of the crystalline semiconductor film manufactured in the first embodiment is measured by EBSP, the <001> orientation is 60% or more in the range of ± 10 ° angle fluctuation on the observation plane A. It is less than 100%, preferably 70% or more and less than 100%.
In the observation plane B, the <001> orientation is 60% or more and less than 100%, preferably 70% or more and less than 100%, within the range of ± 10 ° angular fluctuation, and on the observation surface C, ± 10 °. In the range of the angle fluctuation, the <001> orientation is 60% or more and less than 100%, preferably 70% or more and less than 100%.

In the crystalline semiconductor film formed in this embodiment mode, crystal plane orientations are aligned in one direction or in a direction that can be regarded as substantially one direction.
That is, the property is a semiconductor film close to a single crystal, and the use of such a semiconductor film can greatly improve the performance of the semiconductor device.
For example, when a TFT is formed using this crystalline semiconductor film, field-effect mobility (mobility) equivalent to that of a semiconductor device using a single crystal semiconductor can be obtained.

In addition, in the TFT, an on-current value (a drain current value that flows when the TFT is in an on state), an off-current value (a drain current value that flows when the TFT is in an off state), a threshold voltage , Variation in S value and field effect mobility can be reduced.
Because of such effects, the electrical characteristics of the TFT are improved, and the operating characteristics and reliability of the semiconductor device using the TFT are improved.
Therefore, it is possible to manufacture a semiconductor device that can operate at high speed, has high current driving capability, and has small performance variation among a plurality of elements.

[Embodiment 2]
In this embodiment, a liquid crystal display device which is an example of a semiconductor device will be described with reference to FIGS.
As shown in FIG. 3A, an insulating film 101 functioning as a base film is formed over a substrate 100 as in Embodiment Mode 1, an amorphous semiconductor film 102 is formed over the insulating film 101, and amorphous A cap film 103 is formed on the porous semiconductor film 102.

Here, a glass substrate is used as the substrate 100, and a silicon nitride film containing oxygen having a thickness of 40 to 60 nm and a silicon oxide film containing nitrogen having a thickness of 80 to 120 nm are formed by a plasma CVD method as the insulating film 101, respectively. To do.
In addition, an amorphous semiconductor film having a thickness of 20 to 80 nm is formed as the amorphous semiconductor film 102 by a plasma CVD method, and the cap film 103 includes oxygen of 200 to 1000 nm or less in a thickness of 200 to 1000 nm by the plasma CVD method. And a silicon nitride film having a composition ratio of nitrogen to silicon of 1.3 to 1.5.

Next, as illustrated in FIG. 3B, the amorphous semiconductor film 102 is irradiated with laser light 104 from the cap film 103, and as a result, a crystalline semiconductor film 105 can be formed over the insulating film 101. .
Note that the laser light 104 at that time has energy that can melt the amorphous semiconductor film 102, and laser light having a wavelength that can be absorbed by the amorphous semiconductor film 102 is selected.
Further, before the irradiation with the laser light 104, heat treatment for removing hydrogen contained in the amorphous semiconductor film or the cap film may be performed.

Here, the second harmonic of YVO ₄ is used as the laser beam 104, and then the cap film 103 is removed.
As a method for removing the cap film 103, various removal methods such as dry etching, wet etching, and polishing can be used. Here, the cap film 103 is removed by a dry etching method.

Next, as illustrated in FIG. 3C, the crystalline semiconductor film 105 is selectively etched to form semiconductor layers 201 to 203.
As a method for etching the crystalline semiconductor film 105, dry etching, wet etching, or the like can be used. Here, after applying a resist on the crystalline semiconductor film 105, exposure and development are performed to form a resist mask. Form.
Using the formed resist mask, the crystalline semiconductor film 105 is selectively etched by a dry etching method in which the SF ₆ : O ₂ flow ratio is 4:15, and then the resist mask is removed.

Next, as illustrated in FIG. 3D, a gate insulating film 204 is formed over the semiconductor layers 201 to 203. The gate insulating film includes silicon nitride, silicon nitride containing oxygen, silicon oxide, and oxide containing nitrogen. A single layer or a stacked structure of silicon or the like is used.
Here, silicon oxide containing nitrogen with a thickness of 115 nm is formed by a plasma CVD method.
After that, gate electrodes 205 to 208 are formed. The gate electrodes 205 to 208 can be formed of a metal or a polycrystalline semiconductor to which an impurity of one conductivity type is added.

In the case of using a metal, tungsten (W), molybdenum (Mo), titanium (Ti), tantalum (Ta), aluminum (Al), or the like can be used.
Further, a metal nitride obtained by nitriding a metal can be used, and in addition, a structure in which a first layer made of the metal nitride and a second layer made of the metal are stacked may be used.
Alternatively, a paste containing fine particles can be discharged onto the gate insulating film using a droplet discharge method, and dried and baked.
Furthermore, a paste containing fine particles can be printed on the gate insulating film by a printing method, dried and fired, and typical examples of the fine particles include gold, copper, an alloy of gold and silver, gold and There are copper alloys, silver-copper alloys, gold-silver-copper alloys, and the like.

  Here, after a tantalum nitride film with a thickness of 30 nm and a tungsten film with a thickness of 370 nm are formed over the gate insulating film 204 by a sputtering method, the tantalum nitride film and the tungsten film are formed using a resist mask formed by a photolithography process. By selectively etching, gate electrodes 205 to 208 having a shape in which the end portion of the tantalum nitride film protrudes outside the end portion of the tungsten film are formed.

Next, an impurity element imparting n-type conductivity and an impurity element imparting p-type conductivity are added to the semiconductor layers 201 to 203 using the gate electrodes 205 to 208 as masks, respectively, so that source and drain regions 209 to 214 and high-concentration impurities are added. Region 215 is formed.
Further, low-concentration impurity regions 216 to 223 overlapping with part of the gate electrodes 205 to 208 are formed.
Further, channel regions 201c to 203c and 203d overlapping with the gate electrodes 205 to 208 are formed.

Note that here, the source and drain regions 209, 210, 213, and 214, the high-concentration impurity region 215, and the low-concentration impurity regions 216, 217, and 220 to 223 are doped with boron which is an impurity element imparting p-type conductivity. .
Further, the source and drain regions 211 and 212 and the low-concentration impurity regions 218 and 219 are doped with phosphorus which is an impurity element imparting n-type conductivity.

After that, heat treatment is performed to activate the impurity element added to the semiconductor layer. Here, heating is performed at 550 ° C. for 4 hours in a nitrogen atmosphere.
Through the above steps, thin film transistors 225 to 227 are formed.
Note that p-channel thin film transistors are formed as the thin film transistors 225 and 227, and n-channel thin film transistors are formed as the thin film transistors 226.
In that case, a p-channel thin film transistor 225 and an n-channel thin film transistor 226 form a driver circuit, and the p-channel thin film transistor 227 functions as an element for applying a voltage to the electrode of the pixel.

Next, as shown in FIG. 4A, a first interlayer insulating film for insulating the gate electrodes and wirings of the thin film transistors 225 to 227 is formed.
Here, a silicon oxide film 231, a silicon nitride film 232, and a silicon oxide film 233 are stacked as the first interlayer insulating film.
Next, wirings 234 to 239 and connection terminals 240 connected to the source and drain regions of the thin film transistors 225 to 227 are formed over the silicon oxide film 233 which is a part of the first interlayer insulating film.
Here, a Ti film 100 nm, an Al film 700 nm, and a Ti film 100 nm are successively formed by sputtering, and then selectively etched using a resist mask formed by a photolithography process, so that wirings 234 to 239 and connection terminals 240 is formed, and then the resist mask is removed.

Next, a second interlayer insulating film 241 is formed over the first interlayer insulating film, the wirings 234 to 239, and the connection terminal 240. The second interlayer insulating film 241 includes a silicon oxide film and silicon nitride. An inorganic insulating film such as a film or a silicon oxynitride film (a silicon oxide film containing nitrogen or a silicon nitride film containing oxygen) can be used, and these insulating films may be formed as a single layer or two or more layers. .
As a method for forming the inorganic insulating film, a sputtering method, an LPCVD method, a plasma CVD method, or the like may be used.

Here, after a silicon nitride film containing oxygen having a thickness of 100 nm to 150 nm is formed by a plasma CVD method, the silicon nitride film containing oxygen is selectively etched using a resist mask formed by a photolithography process. A contact hole reaching the wiring 239 of the thin film transistor 227 and the connection terminal 240 is formed, and a second interlayer insulating film 241 is formed, and then the resist mask is removed.
By forming the second interlayer insulating film 241 as in Embodiment Mode 2, exposure of TFTs and wirings in the driver circuit portion can be prevented and the TFTs can be protected from contaminants.

Next, a first pixel electrode 242 connected to the wiring 239 of the thin film transistor 227 and a conductive layer 244 connected to the connection terminal 240 are formed. When the liquid crystal display device is a translucent liquid crystal display device, The pixel electrode 242 is formed using a light-transmitting conductive film.
In the case where the liquid crystal display device is a reflective liquid crystal display device, the first pixel electrode 242 is formed using a conductive film having reflectivity.
Here, the first pixel electrode 242 and the conductive layer 244 are selectively etched using a resist mask formed by a photolithography process after an ITO film containing 125 nm-thick silicon oxide is formed by a sputtering method. Form.

Next, an insulating film 243 that functions as an alignment film is formed. The insulating film 243 is formed by rubbing after a polymer compound layer such as polyimide or polyvinyl alcohol is formed by a roll coating method, a printing method, or the like. can do.
In addition, SiO ₂ can be formed by vapor deposition with respect to the substrate, and the photoreactive polymer compound is irradiated with polarized UV light to polymerize the photoreactive polymer compound. In this case, a polymer compound layer such as polyimide or polyvinyl alcohol is printed by printing, baked and then rubbed.

Next, as illustrated in FIG. 4B, a second pixel electrode 253 is formed over the counter substrate 251 and an insulating film 254 functioning as an alignment film is formed over the second pixel electrode.
Note that a colored layer 252 may be provided between the counter substrate 251 and the pixel electrode 253.
In that case, as the counter substrate 251, a substrate similar to the substrate 100 can be selected as appropriate.
The second pixel electrode 253 can be formed in a manner similar to that of the first pixel electrode 242, and the insulating film 254 functioning as an alignment film can be formed in the same manner as the insulating film 243.
Further, the colored layer 252 is a layer necessary for performing color display. In the case of the RGB method, a colored layer in which dyes or pigments corresponding to red, green, and blue colors are dispersed corresponds to each pixel. Form.

Next, the substrate 100 and the counter substrate 251 are attached to each other with a sealant 257, and a liquid crystal layer 255 is formed between the substrate 100 and the counter substrate 251.
The liquid crystal layer 255 can be formed by injecting a liquid crystal material into a region surrounded by the insulating films 243 and 254 functioning as alignment films and the sealant 257 by a vacuum injection method using a capillary phenomenon.
Further, a sealant 257 is formed on one of the counter substrates 251, and a liquid crystal material is dropped on a region surrounded by the sealant, and then the counter substrate 251 and the substrate 100 are pressure-bonded with the sealant under reduced pressure, whereby the liquid crystal layer 255 is formed. It can also be formed.

As the sealant 257, a thermosetting epoxy resin, a UV curable acrylic resin, thermoplastic nylon, polyester, or the like can be formed using a dispenser method, a printing method, a thermocompression bonding method, or the like.
Note that the distance between the substrate 100 and the counter substrate 251 can be maintained by spraying a filler over the sealant 257, but here, the sealant 257 is formed using a thermosetting epoxy resin.

In order to maintain a distance between the substrate 100 and the counter substrate 251, a spacer 256 may be provided between the insulating films 243 and 254 functioning as alignment films. As the spacer, an organic resin is applied, and the organic resin Can be formed by etching into a desired shape, typically a columnar shape or a cylindrical shape.
Further, since a bead spacer may be used as the spacer, a bead spacer is used as the spacer 256 here.
Although not illustrated, a polarizing plate is provided on one or both of the substrate 100 and the counter substrate 251.

Next, as shown in FIG. 4C, in the terminal portion 263, a connection terminal connected to the gate wiring and the source wiring of the thin film transistor (in FIG. 4C, connected to the source wiring or the drain wiring). Connection terminal 240 is shown).
An FPC (flexible printed wiring) 262 is connected to the connection terminal 240 via a conductive layer 244 and an anisotropic conductive film 261, and the connection terminal 240 is connected via the conductive layer 244 and the anisotropic conductive film 261. Receive video and clock signals.

In the driver circuit portion 264, a circuit for driving a pixel such as a source driver or a gate driver is formed. Here, an n-channel thin film transistor 226 and a p-channel thin film transistor 225 are provided.
Note that the n-channel thin film transistor 226 and the p-channel thin film transistor 225 form a CMOS circuit.

A plurality of pixels are formed in the pixel portion 265, and a liquid crystal element 258 is formed in each pixel. The liquid crystal element 258 includes a first pixel electrode 242, a second pixel electrode 253, and a gap therebetween. This is a portion where the filled liquid crystal layer 255 overlaps.
Further, the first pixel electrode 242 included in the liquid crystal element 258 is electrically connected to the thin film transistor 227.

Through the above process, a liquid crystal display device can be manufactured. In the liquid crystal display device described in Embodiment 2, the crystal plane orientation is constant in the semiconductor layers of the thin film transistors formed in the driver circuit portion 264 and the pixel portion 265. Aligned in the direction.
Therefore, variation in electrical characteristics of the plurality of thin film transistors can be suppressed, and as a result, a liquid crystal display device capable of high-definition display with less color unevenness and defects can be manufactured.

[Embodiment 3]
In this embodiment, a manufacturing process of a light-emitting device having a light-emitting element which is an example of a semiconductor device will be described.
As shown in FIG. 5A, thin film transistors 225 to 227 are formed over the substrate 100 through the insulating film 101 through the same steps as in Embodiment Mode 2, and the gate electrodes and wirings of the thin film transistors 225 to 227 are insulated. As the first interlayer insulating film to be formed, a silicon oxide film 231, a silicon nitride film 232, and a silicon oxide film 233 are stacked.
Further, wirings 308 to 313 and connection terminals 314 connected to the semiconductor layers of the thin film transistors 225 to 227 are formed over the silicon oxide film 233 which is a part of the first interlayer insulating film.

Next, a second interlayer insulating film 315 is formed over the first interlayer insulating film, the wirings 308 to 313, and the connection terminal 314, and then the first electrode layer 316 connected to the wiring 313 of the thin film transistor 227, and A conductive layer 320 connected to the connection terminal 314 is formed.
The first electrode layer 316 and the conductive layer 320 are formed by forming an ITO film containing 125 nm thick silicon oxide by a sputtering method and then selectively etching it using a resist mask formed by a photolithography process. .
By forming the second interlayer insulating film 315 as in this embodiment mode, exposure of TFTs and wirings in the driver circuit portion can be prevented and the TFTs can be protected from contaminants.

  Next, an organic insulating film 317 is formed to cover an end portion of the first electrode layer 316. Here, after applying and baking photosensitive polyimide, exposure and development are performed to form driver circuits and pixel regions. An organic insulating film 317 is formed so that the first electrode layer 316 and the second interlayer insulating film 315 in the periphery of the pixel region are exposed.

Next, a layer 318 containing a light-emitting substance is formed over the first electrode layer 316 and part of the organic insulating film 317 by an evaporation method. The layer 318 containing the light-emitting substance includes a light-emitting organic compound, Alternatively, an inorganic compound having a light-emitting property is used.
Note that the layer 318 containing a light-emitting substance may be formed using a light-emitting organic compound and a light-emitting inorganic compound.
The layer 318 containing a light-emitting substance is formed using a red light-emitting light-emitting substance, a blue light-emitting light-emitting substance, and a green light-emitting light-emitting substance, respectively. Pixels and green light-emitting pixels can be formed.

Here, as a layer containing a red light-emitting substance, DNTPD is 50 nm, NPB is 10 nm, bis [2,3-bis (4-fluorophenyl) quinoxalinato] iridium (acetylacetonate) (abbreviation: Ir (Fdpq NPB to which ₂ (acac)) is added is formed by laminating 30 nm, Alq ₃ 60 nm, and LiF 1 nm.
Further, as the layer containing a green light-emitting luminescent material, a 50 nm, 10 nm and NPB, coumarin 545T (C545T) 40 nm of Alq ₃ that is added to form 60nm of Alq _3, and LiF was 1nm laminated DNTPD .

Further, as a layer containing a blue light-emitting substance, DNTPD is added to 50 nm, NPB is added to 10 nm, 2,5,8,11-tetra (tert-butyl) perylene (abbreviation: TBP) is added, and 9- [ It is formed by stacking 4- (N-carbazolyl)] phenyl-10-phenylanthracene (abbreviation: CzPA :) at 30 nm, Alq ₃ at 60 nm, and LiF at 1 nm.
Furthermore, by forming a layer containing a luminescent substance using a white luminescent substance, in addition to a red luminescent pixel, a blue luminescent pixel, and a green luminescent pixel, white Alternatively, a light-emitting pixel may be formed.
Note that power consumption can be reduced by providing white light-emitting pixels.

Next, a second electrode layer 319 is formed over the layer 318 containing a light-emitting substance and the organic insulating film 317. Here, an Al film having a thickness of 200 nm is formed by an evaporation method.
As a result, the light-emitting element 321 includes the first electrode layer 316, the layer 318 containing a light-emitting substance, and the second electrode layer 319.

Here, the structure, materials used, functions, and the like of the light-emitting element 321 will be described.
By forming a layer having a light emitting function using an organic compound (hereinafter, referred to as a light emitting layer 343) in the layer 318 containing a light emitting substance, the light emitting element 321 functions as an organic EL (Electro Luminescence) element.
Hereinafter, the structure of the light emitting element 321 will be described in detail with reference to the drawings, and materials, functions, and the like used for the structure will be described in detail.

  Examples of the light-emitting organic compound include 9,10-di (2-naphthyl) anthracene (abbreviation: DNA) and 2-tert-butyl-9,10-di (2-naphthyl) anthracene (abbreviation: t-BuDNA). ), 4,4′-bis (2,2-diphenylvinyl) biphenyl (abbreviation: DPVBi), coumarin 30, coumarin 6, coumarin 545, coumarin 545T, perylene, rubrene, periflanthene, 2,5,8,11-tetra (Tert-butyl) perylene (abbreviation: TBP), 9,10-diphenylanthracene (abbreviation: DPA), 5,12-diphenyltetracene, 4- (dicyanomethylene) -2-methyl-6- [p- (dimethylamino) ) Styryl] -4H-pyran (abbreviation: DCM1), 4- (dicyanomethylene) -2-methyl-6- [2- (di Loridin-9-yl) ethenyl] -4H-pyran (abbreviation: DCM2), 4- (dicyanomethylene) -2,6-bis [p- (dimethylamino) styryl] -4H-pyran (abbreviation: BisDCM) and the like. Can be mentioned.

In addition, bis [2- (4 ′, 6′-difluorophenyl) pyridinato-N, C ² ′] (picolinato) iridium (abbreviation: FIrpic), bis {2- [3 ′, 5′-bis (trifluoromethyl) ) phenyl] pyridinato -N, C ² '} (Pikorinato) iridium _{(abbreviation: Ir (CF 3 ppy) 2} (pic)), tris (2-phenylpyridinato--N, C2') iridium (abbreviation: Ir ( ppy) ₃ ), (acetylacetonato) bis (2-phenylpyridinato-N, C ² ′) iridium (abbreviation: Ir (ppy) ₂ (acac)), (acetylacetonato) bis [2- (2 '- thienyl) pyridinato -N, C ^3'] iridium (abbreviation: Ir (thp) ₂ (acac)), (acetylacetonato) bis (2-phenylquinolinato--N, C ² ') iridium (abbreviation: Ir pq) ₂ (acac)), (acetylacetonato) bis [2- (2'-benzothienyl) pyridinato -N, C ³ '] iridium (abbreviation: release phosphorescence such as Ir (btp) ₂ (acac)) Compounds that can be used can also be used.

  As shown in FIG. 6A, a hole injection layer 341 formed of a hole injection material, a hole transport layer 342 formed of a hole transport material, and light emission on the first electrode layer 316. A light-emitting layer 343 formed of an organic compound, an electron transport layer 344 formed of an electron-transport material, a layer 318 containing a light-emitting material formed of an electron injection layer 345 formed of an electron-inject material, and The light-emitting element 321 illustrated in FIG. 5 may be formed using the second electrode layer 319.

The hole transporting material includes phthalocyanine (abbreviation: H ₂ Pc), copper phthalocyanine (abbreviation: CuPc), vanadyl phthalocyanine (abbreviation: VOPc), and 4,4 ′, 4 ″ -tris (N, N-diphenyl). Amino) triphenylamine (abbreviation: TDATA), 4,4 ′, 4 ″ -tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine (abbreviation: MTDATA), 1,3,5 -Tris [N, N-di (m-tolyl) amino] benzene (abbreviation: m-MTDAB), N, N'-diphenyl-N, N'-bis (3-methylphenyl) -1,1'-biphenyl -4,4'-diamine (abbreviation: TPD), 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (abbreviation: NPB), 4,4'-bis {N- [ 4-di (m-tolyl) amino] Enyl-N-phenylamino} biphenyl (abbreviation: DNTPD), 4,4′-bis [N- (4-biphenylyl) -N-phenylamino] biphenyl (abbreviation: BBPB), 4,4 ′, 4 ″- And tri (N-carbazolyl) triphenylamine (abbreviation: TCTA).

Examples of the hole transporting material include those described above, but are not limited thereto. Among the compounds described above, aromatic amine compounds typified by TDATA, MTDATA, m-MTDAB, TPD, NPB, DNTPD, BBPB, TCTA, and the like are prone to generate holes and are a group of compounds suitable as organic compounds. It is. The substances mentioned here are mainly substances having a hole mobility of 10 ⁻⁶ cm ² / Vs or higher.

As the hole injecting material, there is a material obtained by chemically doping a conductive polymer compound in addition to the above hole transporting material. Polyethylenedioxythiophene (abbreviation: PEDOT) doped with polystyrene sulfonic acid (abbreviation: PSS). ) And polyaniline (abbreviation: PAni) can also be used.
Also effective are thin films of inorganic semiconductors such as molybdenum oxide (MoO _x ), vanadium oxide (VO _x ), nickel oxide (NiO _x ), and ultra-thin films of inorganic insulators such as aluminum oxide (Al ₂ O ₃ ). .

The electron transporting material, tris (8-quinolinolato) aluminum (abbreviation: Alq3), tris (4-methyl-8-quinolinolato) aluminum (abbreviation: Almq _3), bis (10-hydroxybenzo [h] - Quinolinato) beryllium (abbreviation: BeBq ₂ ), bis (2-methyl-8-quinolinolato) -4-phenylphenolato-aluminum (abbreviation: BAlq), or a material made of a metal complex having a quinoline skeleton or a benzoquinoline skeleton is used. be able to.
In addition, bis [2- (2-hydroxyphenyl) benzoxazolate] zinc (abbreviation: Zn (BOX) ₂ ), bis [2- (2-hydroxyphenyl) benzothiazolate] zinc (abbreviation: Zn (BTZ) ₂ ) and other materials such as metal complexes having an oxazole-based or thiazole-based ligand can also be used.

In addition to metal complexes, 2- (4-biphenylyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis [5- (P-tert-butylphenyl) -1,3,4-oxadiazol-2-yl] benzene (abbreviation: OXD-7), 3- (4-tert-butylphenyl) -4-phenyl-5- ( 4-biphenylyl) -1,2,4-triazole (abbreviation: TAZ), 3- (4-tert-butylphenyl) -4- (4-ethylphenyl) -5- (4-biphenylyl) -1,2, 4-triazole (abbreviation: p-EtTAZ), bathophenanthroline (abbreviation: BPhen), bathocuproin (abbreviation: BCP), and the like can be used.
The substances mentioned here are mainly substances having an electron mobility of 10 ⁻⁶ cm ² / Vs or higher.

Examples of the electron injection material include alkali metal halides such as LiF and CsF, alkaline earth halides such as CaF ₂ , and alkali metal oxides such as Li ₂ O in addition to the electron transport materials described above. Insulator ultrathin films are often used.
In addition, alkali metal complexes such as lithium acetylacetonate (abbreviation: Li (acac) and 8-quinolinolato-lithium (abbreviation: Liq) are also effective. Furthermore, the above-described electron transporting materials, Mg, Li, Cs, and the like It is also possible to use a material in which a metal having a small work function is mixed by co-evaporation or the like.

  In addition, as illustrated in FIG. 6B, the first electrode layer 316 and a hole transport layer 346 formed using a light-emitting organic compound and an inorganic compound having an electron-accepting property with respect to the light-emitting organic compound. And a light emitting layer 343 formed of a light emitting organic compound and a light emitting layer formed by an electron transporting layer 347 formed of a light emitting organic compound and an inorganic compound having an electron donating property to the light emitting organic compound. The light-emitting element 321 illustrated in FIG. 5 may be formed using the layer 318 containing a material and the second electrode layer 319.

The hole-transport layer 346 formed using a light-emitting organic compound and an inorganic compound having an electron-accepting property with respect to the light-emitting organic compound appropriately uses the above-described hole-transport organic compound as the organic compound. Form.
The inorganic compound may be anything as long as it can easily receive electrons from an organic compound, and various metal oxides or metal nitrides can be used. Any one of Groups 4 to 12 of the periodic table can be used. These transition metal oxides are preferable because they easily exhibit electron accepting properties.

Specific examples include titanium oxide, zirconium oxide, vanadium oxide, molybdenum oxide, tungsten oxide, rhenium oxide, ruthenium oxide, and zinc oxide.
Among the metal oxides mentioned above, transition metal oxides of any of Groups 4 to 8 of the periodic table are often a group having a high electron accepting property, and are a preferable group. In particular, vanadium oxide, molybdenum oxide, tungsten oxide. Rhenium oxide is suitable because it can be vacuum-deposited and is easy to handle.

The electron-transport layer 347 formed using a light-emitting organic compound and an inorganic compound having an electron-donating property with respect to the light-emitting organic compound is formed using the above-described electron-transport organic compound as appropriate as the organic compound.
The inorganic compound may be anything as long as it easily gives an electron to the organic compound, and various metal oxides or metal nitrides can be used. Alkali metal oxides, alkaline earth metal oxides can be used. Rare earth metal oxides, alkali metal nitrides, alkaline earth metal nitrides, and rare earth metal nitrides are preferred because they easily exhibit electron donating properties.
Specific examples include lithium oxide, strontium oxide, barium oxide, erbium oxide, lithium nitride, magnesium nitride, calcium nitride, yttrium nitride, and lanthanum nitride. In particular, lithium oxide, barium oxide, lithium nitride, magnesium nitride, and calcium nitride are preferable because they can be vacuum-deposited and are easy to handle.

Since the electron transport layer 347 or the hole transport layer 346 formed of a light-emitting organic compound and an inorganic compound has excellent electron injection / transport characteristics, both the first electrode layer 316 and the second electrode layer 319 are Various materials can be used with almost no work function limitation.
Further, the driving voltage can be reduced.

In addition, the light-emitting element 321 functions as an inorganic EL element by including a layer having a light-emitting function using an inorganic compound (hereinafter referred to as a light-emitting layer 349) as the layer 318 containing a light-emitting substance.
The inorganic EL element is classified into a dispersion-type inorganic EL element and a thin-film inorganic EL element depending on the element configuration, and the former has a layer containing a light-emitting substance in which particles of a light-emitting material are dispersed in a binder, The latter is different in that it has a layer containing a luminescent material made of a thin film of a luminescent material, but is common in that it requires electrons accelerated in a high electric field.

Furthermore, as the light emission mechanism obtained, there are donor-acceptor recombination light emission using a donor level and an acceptor level, and localized light emission using a core electron transition of a metal ion.
In general, the dispersion-type inorganic EL often has donor-acceptor recombination light emission, and the thin-film inorganic EL element often has localized light emission. The structure of the inorganic EL element is shown below.

A light-emitting material that can be used in Embodiment Mode 3 includes a base material and an impurity element serving as a light emission center, and light emission of various colors can be obtained by changing the impurity element to be contained.
Various methods such as a solid phase method and a liquid phase method (coprecipitation method) can be used as a method for producing a luminescent material. In addition, a spray pyrolysis method, a double decomposition method, and a method using a precursor thermal decomposition reaction. In addition, a reverse micelle method, a method combining these methods with high-temperature baking, a liquid phase method such as a freeze-drying method, and the like can also be used.

The solid phase method is a method in which a base material and an impurity element or a compound thereof are weighed, mixed in a mortar, heated and fired in an electric furnace, reacted, and the base material contains impurities.
The firing temperature is preferably 700 to 1500 ° C., because the solid phase reaction does not proceed when the temperature is too low, and the base material is decomposed when the temperature is too high.
Although it may be fired in a powder state, it is preferable to fire in a pellet state and it requires firing at a relatively high temperature. However, since it is a simple method, it has high productivity and is suitable for mass production. ing.

The liquid phase method (coprecipitation method) is a method in which a base material or a compound thereof and an impurity element or a compound thereof are reacted in a solution, dried, and then fired. Particles of the base material that is a light-emitting material Are uniformly distributed, and the reaction can proceed even at a low firing temperature with a small particle size.
As a base material used for the light-emitting material, sulfide, oxide, or nitride can be used.

Examples of the sulfide include zinc sulfide (ZnS), cadmium sulfide (CdS), calcium sulfide (CaS), yttrium sulfide (Y ₂ S ₃ ), gallium sulfide (Ga ₂ S ₃ ), strontium sulfide (SrS), Barium sulfide (BaS) or the like can be used, and as the oxide, for example, zinc oxide (ZnO), yttrium oxide (Y ₂ O ₃ ), or the like can be used.

As the nitride, for example, aluminum nitride (AlN), gallium nitride (GaN), indium nitride (InN), or the like can be used.
Furthermore, zinc selenide (ZnSe), zinc telluride (ZnTe), and the like can also be used. Calcium sulfide-gallium (CaGa ₂ S ₄ ), strontium sulfide-gallium (SrGa ₂ S ₄ ), barium sulfide-gallium (BaGa) _It may be a ternary mixed crystal such as ₂ S ₄ ).

As emission centers of localized emission, manganese (Mn), copper (Cu), samarium (Sm), terbium (Tb), erbium (Er), thulium (Tm), europium (Eu), cerium (Ce), praseodymium (Pr) or the like can be used.
Note that a halogen element such as fluorine (F) or chlorine (Cl) may be added as charge compensation.

On the other hand, a light-emitting material containing a first impurity element that forms a donor level and a second impurity element that forms an acceptor level can be used as the emission center of donor-acceptor recombination light emission.
For example, fluorine (F), chlorine (Cl), aluminum (Al), or the like can be used as the first impurity element. Examples of the second impurity element include copper (Cu), silver (Ag), and the like. Can be used.

When a light-emitting material for donor-acceptor recombination light emission is synthesized using a solid-phase method, a base material, a first impurity element or a compound thereof, and a second impurity element or a compound thereof are weighed, and a mortar After mixing, heat and bake in an electric furnace.
The firing temperature at that time is preferably 700 to 1500 ° C., because the solid phase reaction does not proceed when the temperature is too low, and the base material is decomposed when the temperature is too high.
In addition, although baking may be performed in a powder state, it is preferable to perform baking in a pellet state.

As the base material, the above-described base material can be used, and as the first impurity element or the compound thereof, for example, fluorine (F), chlorine (Cl), aluminum sulfide (Al ₂ S ₃ ), or the like is used. be able to.
As the second impurity element or compound thereof, for example, copper (Cu), silver (Ag), copper sulfide (Cu ₂ S), silver sulfide (Ag ₂ S), or the like can be used.

In addition, as the impurity element in the case of using the solid phase reaction, a compound composed of the first impurity element and the second impurity element may be used in combination. In this case, the impurity element is easily diffused, and the solid phase Since the reaction easily proceeds, a uniform light emitting material can be obtained.
Further, since no extra impurity element is contained, a light-emitting material with high purity can be obtained.
As the compound composed of the first impurity element and the second impurity element at that time, for example, copper chloride (CuCl), silver chloride (AgCl), or the like can be used.
Note that the concentration of these impurity elements may be 0.01 to 10 atom%, preferably 0.05 to 5 atom% with respect to the base material.

FIG. 6C illustrates a cross section of an inorganic EL element in which a layer 318 containing a light-emitting substance includes a first insulating layer 348, a light-emitting layer 349, and a second insulating layer 350.
Note that an inorganic EL light-emitting element can emit light by applying a voltage between a pair of electrode layers sandwiching a layer containing a light-emitting substance, but can operate in either DC driving or AC driving.
In the case of a thin-film inorganic EL, the light emitting layer 349 is a layer containing the above light emitting material, and is a physical vapor deposition method (such as a resistance heating vapor deposition method, a vacuum vapor deposition method such as an electron beam vapor deposition (EB vapor deposition) method, or a sputtering method ( PVD), metal organic chemical vapor deposition (CVD), chemical vapor deposition (CVD) such as hydride transport low pressure CVD, atomic epitaxy (ALE), or the like.

The first insulating layer 348 and the second insulating layer 350 are not particularly limited. However, the first insulating layer 348 and the second insulating layer 350 have high insulation resistance, preferably have a dense film quality, and preferably have a high dielectric constant.
For example, silicon oxide (SiO ₂ ), yttrium oxide (Y ₂ O ₃ ), titanium oxide (TiO ₂ ), aluminum oxide (Al ₂ O ₃ ), hafnium oxide (HfO ₂ ), tantalum oxide (Ta ₂ O ₅ ), Barium titanate (BaTiO ₃ ), strontium titanate (SrTiO ₃ ), lead titanate (PbTiO ₃ ), silicon nitride (Si ₃ N ₄ ), zirconium oxide (ZrO ₂ ), etc., or a mixed film thereof or two or more kinds A laminated film can be used.

The first insulating layer 348 and the second insulating layer 350 can be formed by sputtering, vapor deposition, CVD, or the like. The film thickness is not particularly limited, but is preferably in the range of 10 to 1000 nm. .
Note that since the light-emitting element of Embodiment 3 does not necessarily require hot electrons, the light-emitting element can be formed into a thin film and has an advantage that the driving voltage can be reduced.
The film thickness is preferably 500 nm or less, more preferably 100 nm or less.

Although not illustrated, a buffer layer may be provided between the light-emitting layer 349 and the insulating layers 348 and 350, or between the light-emitting layer 349 and the electrode layers 316 and 319. The buffer layer facilitates carrier injection and It has a role to suppress mixing of layers.
The buffer layer is not particularly limited. For example, ZnS, ZnSe, ZnTe, CdS, SrS, BaS, CuS, Cu ₂ S, LiF, CaF ₂ , BaF ₂ , which are base materials of the light emitting layer, Alternatively, MgF ₂ or the like can be used.

In addition, as illustrated in FIG. 6D, the layer 318 containing a light-emitting substance may be formed of a light-emitting layer 349 and a first insulating layer 348. In this case, in FIG. The insulating layer 348 is provided between the second electrode layer 319 and the light-emitting layer 349.
Note that the first insulating layer 348 may be provided between the first electrode layer 316 and the light-emitting layer 349.
Further, the layer 318 containing a light-emitting substance may be formed using only the light-emitting layer 349. That is, the light-emitting element 321 may be formed using the first electrode layer 316, the layer 318 containing a light-emitting substance, and the second electrode layer 319.

In the case of a dispersion-type inorganic EL, a particulate luminescent material is dispersed in a binder to form a layer containing a film-like luminescent material, but particles having a desired size cannot be obtained sufficiently by the method for producing the luminescent material. In such a case, the particles may be processed into particles by pulverization with a mortar or the like.
Note that the binder is a substance for fixing a granular light emitting material in a dispersed state and maintaining the shape as a layer containing a light emitting substance, and the light emitting material is uniform in the layer containing the light emitting substance by the binder. Dispersed and fixed in

In the case of a dispersion-type inorganic EL, a method for forming a layer containing a light-emitting substance includes a droplet discharge method that can selectively form a layer containing a light-emitting substance, a printing method (screen printing, offset printing, etc.) An application method, a dipping method, a dispenser method, or the like can also be used.
The thickness of the layer at that time is not particularly limited, but is preferably in the range of 10 to 1000 nm.
In the layer containing a light-emitting material including a light-emitting material and a binder, the ratio of the light-emitting material is preferably 50 wt% or more and 80 wt% or less.

The element in FIG. 6E includes a first electrode layer 316, a layer 318 containing a light-emitting substance, and a second electrode layer 319. In the layer 318 containing a light-emitting substance, a light-emitting material 352 is dispersed in a binder 351. A light emitting layer and an insulating layer 348.
Note that the insulating layer 348 has a structure in contact with the second electrode layer 319 in FIG. 6E; however, the insulating layer 348 may have a structure in contact with the first electrode layer 316, and further, the first electrode layer. An insulating layer in contact with 316 and the second electrode layer 319 may be formed.
Further, the element does not have to have an insulating layer in contact with the first electrode layer 316 and the second electrode layer 319.

As a binder that can be used in Embodiment Mode 3, an insulating material such as an organic material or an inorganic material can be used, and a mixed material of an organic material and an inorganic material may be used.
As the organic insulating material, a polymer having a relatively high dielectric constant, such as cyanoethyl cellulose resin, or a resin such as polyethylene, polypropylene, polystyrene resin, silicone resin, siloxane resin, epoxy resin, or vinylidene fluoride may be used. it can.
Moreover, you may use heat resistant polymers, such as aromatic polyamide and polybenzimidazole.

Note that the siloxane resin corresponds to a resin including a Si—O—Si bond, and the siloxane has a skeleton structure formed of a bond of silicon (Si) and oxygen (O).
As the substituent, an organic group containing at least hydrogen (for example, an alkyl group or an aromatic hydrocarbon group) may be used, and a fluoro group may be used. Further, as a substituent, an organic group containing at least hydrogen and a fluoro group may be used. And may be used.

In addition, resin materials such as vinyl resins such as polyvinyl alcohol and polyvinyl butyral, phenol resins, novolac resins, acrylic resins, melamine resins, urethane resins, and oxazole resins (polybenzoxazole) may be used. Can be used.
Further, the dielectric constant can be adjusted by appropriately mixing fine particles having a high dielectric constant such as barium titanate (BaTiO ₃ ) and strontium titanate (SrTiO ₃ ) with these resins.

Examples of the inorganic material used for the binder include silicon oxide (SiO _x ), silicon nitride (SiN _x ), silicon containing oxygen and nitrogen, aluminum nitride (AlN), aluminum containing oxygen and nitrogen, and aluminum oxide (Al ₂ O ₃ ), titanium oxide (TiO ₂ ), BaTiO ₃ , SrTiO ₃ , lead titanate (PbTiO ₃ ), potassium niobate (KNbO ₃ ), lead niobate (PbNbO ₃ ), tantalum oxide (Ta ₂ O ₅ ), tantalum Forming with a material selected from substances including barium oxide (BaTa ₂ O ₆ ), lithium tantalate (LiTaO ₃ ), yttrium oxide (Y ₂ O ₃ ), zirconium oxide (ZrO ₂ ), ZnS and other inorganic materials. Can do.
By including an inorganic material having a high dielectric constant in the organic material (by addition or the like), the dielectric constant of the layer containing the light emitting material including the light emitting material and the binder can be further controlled, and the dielectric constant can be further increased. Can do.

In the manufacturing process, the light-emitting material is dispersed in a solution containing a binder. As a solvent for the solution containing the binder that can be used in this embodiment mode, the binder material is dissolved and the light-emitting layer has a desired thickness. A solvent capable of producing a solution having a viscosity suitable for forming the film may be appropriately selected.
For this, an organic solvent or the like can be used. For example, when a siloxane resin is used as a binder, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate (also referred to as PGMEA), 3-methoxy-3-methyl-1-butanol ( It is also possible to use MMB).

Next, as illustrated in FIG. 5B, a protective film 322 is formed over the second electrode layer 319.
The protective film is for preventing moisture, oxygen, and the like from entering the light-emitting element 321 and the protective film 322. The protective film 322 is formed by a thin film formation method such as a plasma CVD method or a sputtering method, and silicon nitride. Silicon oxide, silicon nitride oxide, silicon oxynitride, aluminum oxynitride, or aluminum oxide, diamond-like carbon (DLC), nitrogen-containing carbon (CN), or other insulating materials are preferably used.

Further, the sealing substrate 324 is bonded to the second interlayer insulating film 315 formed over the substrate 100 with the sealing material 323, whereby the space 325 surrounded by the substrate 100, the sealing substrate 324, and the sealing material 323 is formed. The light emitting element 321 is provided.
Note that the space 325 is filled with a filler, and may be filled with a sealant 323 in addition to an inert gas (such as nitrogen or argon).

Note that an epoxy-based resin is preferably used for the sealant 323, and these materials are preferably materials that do not transmit moisture and oxygen as much as possible.
In addition to a glass substrate or a quartz substrate, a plastic substrate made of FRP (Fiberglass-Reinforced Plastics), PVF (polyvinyl fluoride), Mylar, polyester, acrylic, or the like can be used as a material used for the sealing substrate 324.

Next, as illustrated in FIG. 5C, the FPC 327 is attached to the conductive layer 320 in contact with the connection terminal 314 using the anisotropic conductive layer 326 as in Embodiment Mode 2.
Through the above steps, a semiconductor device having an active matrix light-emitting element can be formed.

Here, FIG. 7 shows an equivalent circuit diagram of a pixel in the case of full-color display in the third embodiment.
In FIG. 7, a thin film transistor 331 surrounded by a broken line corresponds to a thin film transistor that switches the driving thin film transistor 227 in FIG. 5A, and a thin film transistor 332 surrounded by a broken line corresponds to a thin film transistor that drives a light emitting element. Yes.
Note that as the light-emitting element, a mode using an organic EL element (hereinafter referred to as an OLED) in which a layer containing a light-emitting substance is formed using a layer containing a light-emitting organic compound will be described.

In the pixel displaying red, an OLED 334R that emits red light is connected to a drain region of the thin film transistor 332, and a red anode side power line 337R is provided in a source region.
The OLED 334R is provided with a cathode side power supply line 333, the switching thin film transistor 331 is connected to the gate wiring 336, and the gate electrode of the driving thin film transistor 332 is connected to the drain region of the switching thin film transistor 331. Is done.
Note that the drain region of the switching thin film transistor 331 is connected to the capacitor element 338 connected to the red anode-side power line 337R.

In the pixel displaying green, an OLED 334G that emits green light is connected to the drain region of the driving thin film transistor 332, and a green anode-side power line 337G is provided in the source region.
The OLED 334G is provided with a cathode side power supply line 333, the switching thin film transistor 331 is connected to the gate wiring 336, and the gate electrode of the driving thin film transistor 332 is connected to the drain region of the switching thin film transistor 331. Is done.
Note that the drain region of the switching thin film transistor 331 is connected to the capacitor element 338 connected to the green anode power supply line 337G.

In the pixel displaying blue, an OLED 334B that emits blue light is connected to the drain region of the driving thin film transistor 332, and a blue anode-side power line 337B is provided in the source region.
The OLED 334B is provided with a cathode side power supply line 333, the switching thin film transistor 331 is connected to the gate wiring 336, and the gate electrode of the driving thin film transistor 332 is connected to the drain region of the switching thin film transistor 331. Is done.
Note that the drain region of the switching thin film transistor 331 is connected to the capacitor 338 connected to the blue anode power supply line 337B.

Different voltages are applied to the pixels of different colors depending on the material of the layer containing the light-emitting substance.
Here, the source wiring 335 and the anode side power supply lines 337R, 337G, and 337B are formed in parallel. However, the present invention is not limited to this, and the gate wiring 336 and the anode side power supply lines 337R, 337G, and 337B are parallel. It may be formed.
Further, the driving thin film transistor 332 may have a multi-gate electrode structure.

In the light-emitting device, the screen display driving method is not particularly limited, and for example, a dot sequential driving method, a line sequential driving method, a surface sequential driving method, or the like may be used. A time-division gradation driving method or an area gradation driving method may be used as appropriate.
The video signal input to the source line of the light emitting device may be an analog signal or a digital signal, and a drive circuit or the like may be designed in accordance with the video signal as appropriate.

In a light emitting device with a digital video signal, a video signal input to a pixel has a constant voltage (CV) and a constant current (CC), and the video signal has a constant voltage (CV). In some cases, there are a constant voltage (CVCV) of a signal applied to the light emitting element and a constant voltage (CVCC) of a signal applied to the light emitting element.
The video signal having a constant current (CC) includes a signal having a constant voltage applied to the light emitting element (CCCV) and a signal having a constant current applied to the light emitting element (CCCC). is there.
Further, a protective circuit (such as a protective diode) for preventing electrostatic breakdown may be provided in the light emitting device.

Through the above process, a light-emitting device having an active matrix light-emitting element can be manufactured.
In the light-emitting device described in this embodiment, crystal plane orientations are aligned in a certain direction in a semiconductor layer of a thin film transistor formed in a driver circuit or a pixel portion; therefore, variation in electrical characteristics of the thin film transistor that drives the light-emitting element Can be suppressed.
As a result, variation in luminance of the light-emitting element can be reduced, and a light-emitting device capable of high-definition display with less color unevenness and defects can be manufactured.

[Embodiment 4]
In this embodiment, a manufacturing process of a semiconductor device capable of transmitting data without contact will be described with reference to FIGS.
In addition, a structure of the semiconductor device is described with reference to FIGS.

As shown in FIG. 8A, a separation film 402 is formed over a substrate 401.
Next, as in Embodiments 1 and 2, an insulating film 403 is formed over the separation film 402, and a thin film transistor 404 is formed over the insulating film 403.
Subsequently, an interlayer insulating film 405 that insulates a conductive film included in the thin film transistor 404 is formed, and a source electrode and a drain electrode 406 connected to the semiconductor layer of the thin film transistor 404 are formed.

After that, an insulating film 407 is formed to cover the thin film transistor 404, the interlayer insulating film 405, and the source and drain electrodes 406, and a conductive film 408 connected to the source or drain electrode 406 through the insulating film 407 is formed.
Note that a substrate similar to the substrate 100 can be used as the substrate 401.
As the substrate, a metal substrate or a stainless steel substrate with an insulating film formed thereon, a heat-resistant plastic substrate that can withstand the processing temperature in this step, or the like can be used. Here, a glass substrate is used as the substrate 401. Use.

The release film 402 is formed of tungsten (W), molybdenum (Mo), titanium (Ti), tantalum (Ta), niobium (Nb), nickel (Ni), sputtering, plasma CVD, coating, printing, or the like. An element selected from cobalt (Co), zirconium (Zr), zinc (Zn), ruthenium (Ru), rhodium (Rh), palladium (Pd), osmium (Os), iridium (Ir), silicon (Si), Alternatively, a layer formed of an alloy material containing an element as a main component or a compound material containing an element as a main component is formed as a single layer or a stacked layer.
Note that the crystal structure of the layer containing silicon which is the separation layer 402 may be any of amorphous, microcrystalline, and polycrystalline.

In the case where the separation film 402 has a single-layer structure, a tungsten layer, a molybdenum layer, or a layer containing a mixture of tungsten and molybdenum is preferably formed.
Alternatively, a layer containing tungsten oxide or oxynitride, a layer containing molybdenum oxide or oxynitride, or a layer containing an oxide or oxynitride of a mixture of tungsten and molybdenum is formed.
Note that the mixture of tungsten and molybdenum corresponds to, for example, an alloy of tungsten and molybdenum.

In the case where the separation film 402 has a stacked structure, preferably, a tungsten layer, a molybdenum layer, or a layer containing a mixture of tungsten and molybdenum is formed as a first layer, and tungsten, molybdenum, or tungsten and molybdenum is formed as a second layer. To form oxides, nitrides, oxynitrides or nitride oxides.
In the case where a layered structure of a layer containing tungsten and a layer containing tungsten oxide is formed as the release film 402, a layer containing tungsten is formed, and an insulating film formed of an oxide is formed thereover. Alternatively, the fact that a layer containing an oxide of tungsten is formed at the interface between the tungsten layer and the insulating film may be utilized.

Furthermore, the surface of the layer containing tungsten is subjected to thermal oxidation treatment, oxygen plasma treatment, N ₂ O plasma treatment, treatment with a solution having strong oxidizing power such as ozone water, treatment with water to which hydrogen is added, and the like. Alternatively, a layer containing an oxide of tungsten may be formed.
The same applies to the case where a layer containing tungsten nitride, oxynitride, and nitride oxide is formed. After a layer containing tungsten is formed, a silicon nitride layer, a silicon oxynitride layer, and a silicon nitride oxide layer are formed thereon. A layer may be formed.

Tungsten oxide is represented by WO _x . x is in the range of 2 ≦ x ≦ 3, when x is 2 (WO ₂ ), when x is 2.5 (W ₂ O ₅ ), when x is 2.75 (W ₄ O ₁₁ ) X is 3 (WO ₃ ).
Here, a tungsten film having a thickness of 20 to 100 nm, preferably 40 to 80 nm, is formed by a sputtering method.
Note that according to the above process, the separation film 402 is formed so as to be in contact with the substrate 401, but the present invention is not limited to this process, and an insulating film serving as a base is formed so as to be in contact with the substrate 401. Alternatively, the separation film 402 may be provided so as to be in contact with the insulating film.

The insulating film 403 formed over the separation film can be formed in a manner similar to that of the insulating film 101. Here, a tungsten oxide film is formed on the surface of the separation film 402 by generating plasma while flowing N ₂ O gas. After that, a silicon oxide film containing nitrogen is formed by a plasma CVD method.
The thin film transistor 404 can be formed in a manner similar to that of the thin film transistors 225 to 227 described in Embodiment 2.
The source and drain electrodes 406 can be formed in a manner similar to the wirings 234 to 239 described in Embodiment 2.

The interlayer insulating film 405 and the insulating film 407 that cover the source and drain electrodes 406 can be formed by applying and baking polyimide, acrylic, or siloxane polymer. However, sputtering, plasma CVD, application, printing By a method or the like, a single layer or a stacked layer may be formed using an inorganic compound.
Typical examples of the inorganic compound include silicon oxide, silicon nitride, and silicon oxynitride.

Next, as illustrated in FIG. 8B, a conductive film 411 is formed over the conductive film 408.
Here, a composition having gold particles is printed by a printing method, heated at 200 ° C. for 30 minutes, and the composition is baked to form the conductive film 411.

Next, as illustrated in FIG. 8C, an insulating film 412 is formed to cover end portions of the insulating film 407 and the conductive film 411. Here, the insulating film covers end portions of the insulating film 407 and the conductive film 411. 412 is formed using an epoxy resin.
In that case, the composition of the epoxy resin is applied by spin coating, heated at 160 ° C. for 30 minutes, the insulating film covering the conductive film 411 is removed, the conductive film 411 is exposed, and the thickness is increased. An insulating film 412 having a thickness of 1 to 20 μm, preferably 5 to 10 μm is formed.
Note that here, a stacked body from the insulating film 403 to the insulating film 412 is referred to as an element formation layer 410.

Next, as illustrated in FIG. 8D, the insulating films 403, 405, and 407, and the insulating film 412 are irradiated with laser light 413 in order to easily perform the subsequent peeling step, so that FIG. An opening 414 as shown in FIG. 6 is formed, and then an adhesive member 415 is bonded to the insulating film 412.
As the laser light irradiated to form the opening 414, a laser beam having a wavelength absorbed by the insulating films 403, 405, and 407 or the insulating film 412 is preferable. Typically, an ultraviolet region, a visible region, Alternatively, the laser beam in the infrared region is appropriately selected and irradiated.

Examples of laser oscillators that can oscillate such laser light include excimer laser oscillators such as KrF, ArF, and XeCl, gas laser oscillators such as He, He—Cd, Ar, He—Ne, HF, and CO ₂ . Crystals such as YAG, GdVO ₄ , YVO ₄ , YLF, and YAlO ₃ doped with Cr, Nd, Er, Ho, Ce, Co, Ti, or Tm, solid laser oscillators such as glass and ruby, GaN, GaAs, and GaAlAs A semiconductor laser oscillator such as InGaAsP can be used.
In the solid-state laser oscillator, it is preferable to appropriately apply the fundamental wave to the fifth harmonic.

As a result of the laser irradiation, the insulating films 403, 405, 407, and 412 absorb the laser light 413 and are melted to form openings.
Note that throughput can be improved by omitting the step of irradiating the insulating films 403, 405, and 407 and the insulating film 412 with the laser light 413.

Next, as shown in FIG. 9A, in the metal oxide film formed at the interface between the separation film 402 and the insulating film 403, the substrate 401 having the separation film and the part 421 of the element formation layer are physically attached. Peel off.
The physical means in this case refers to a mechanical means or a mechanical means, and means a means for changing some mechanical energy (mechanical energy). The means is typically a mechanical force. Adding (for example, a process of peeling with a human hand or a grip jig, or a process of separating while rotating the roller with the roller as a fulcrum).

The above peeling process has a layer that does not shrink by heat treatment, a layer that shrinks by heat treatment, and an intermediate layer between them. By performing heat treatment when the peeling process is completed or during the peeling process, the overstress state is intermediate. It is characterized in that it is applied in the layer or in the vicinity thereof, and then peeled off in the intermediate layer or in the vicinity thereof by applying a stimulus.
In that case, in the heat treatment such as crystallization of the amorphous silicon film, activation of impurities, and hydrogen extraction, the separation film 402 does not contract, but the insulating film 403 and the insulating film 412 contract, and further the separation film A tungsten oxide layer (WO _x , 2 ≦ x ≦ 3) is formed at the interface between 402 and the insulating film 403.
Since the tungsten oxide layer is fragile, it is easily separated by the physical means. As a result, a part 421 of the element formation layer can be peeled from the substrate 401 by the physical means.

In the fourth embodiment, the metal oxide film is formed between the peeling film and the insulating film, and the element forming layer 410 is peeled off by physical means. However, the present invention is not limited to this.
A light-transmitting substrate is used as the substrate, an amorphous silicon layer containing hydrogen is used as the separation film, and laser light is irradiated from the substrate side to the amorphous silicon film after the step of FIG. A method can be used in which hydrogen contained is vaporized and separated between the substrate and the separation film.

Further, after the step of FIG. 8E, a method of mechanically polishing and removing the substrate or a method of removing the substrate by dissolving the substrate with a solution of HF or the like can be used. It is not necessary to use a film.
Further, in FIG. 8E, before bonding the adhesive member 415 to the insulating film 412, a fluorinated gas such as NF ₃ , BrF ₃ , or ClF ₃ is introduced into the opening 414, and the release film is made of fluorinated gas. After etching and removing, a method in which an adhesive member 415 is attached to the insulating film 412 and a part 421 of the element formation layer is peeled from the substrate can be used.

Further, in FIG. 8E, before the adhesive member 415 is attached to the insulating film 412, a fluorine gas such as NF ₃ , BrF ₃ , or ClF ₃ is introduced into the opening 414 so that a part of the separation film is covered. After the etching gas is removed by etching, an adhesive member 415 is attached to the insulating film 412, and a part 421 of the element formation layer is peeled off from the substrate by a physical means.

Next, as illustrated in FIG. 9B, the flexible substrate 422 is attached to the insulating film 403 of the part 421 of the element formation layer, and then the adhesive member 415 is peeled from the part 421 of the element formation layer.
Here, a film formed of polyaniline by a casting method is used as the flexible substrate 422, and then the flexible substrate 422 is attached to the UV sheet 431 of the dicing frame 432 as shown in FIG. 9C. However, since the UV sheet 431 has adhesiveness, the flexible substrate 422 is fixed on the UV sheet 431.
After that, the conductive film 411 may be irradiated with laser light to improve the adhesion between the conductive film 411 and the conductive film 408.
Subsequently, as illustrated in FIG. 9D, a connection terminal 433 is formed over the conductive film 411.
By forming the connection terminal 433, it is possible to easily perform alignment and adhesion with a conductive film that functions as an antenna later.

Next, as illustrated in FIG. 10A, a part 421 of the element formation layer is divided.
Here, the part 421 of the element formation layer and the flexible substrate 422 are irradiated with laser light 434, so that the part 421 of the element formation layer is divided into a plurality of portions as illustrated in FIG.
As the laser light 434, the laser light 413 can be selected as appropriate from the laser light 413, and here, the insulating films 403, 405, 407, the insulating film 412, and the flexible substrate 422 absorb the laser light 434. It is preferable to select a possible laser beam.
Here, although a part of the element formation layer is divided into a plurality of parts by using the laser cut method, a dicing method, a scribing method, or the like can be appropriately used instead of this method, and as a result, the divided element formation is performed. The layers are denoted as thin film integrated circuits 442a, 442b.

Next, as shown in FIG. 10C, the UV sheet of the dicing frame 432 is irradiated with UV light to reduce the adhesive strength of the UV sheet 431, and then the UV sheet 431 is supported by the expander frame 444. .
At that time, the width of the groove 441 formed between the thin film integrated circuits 442a and 442b can be increased by supporting the expander frame 444 while extending the UV sheet 431.
Note that the enlarged groove 446 is preferably matched with the size of the antenna substrate to be bonded to the thin film integrated circuits 442a and 442b later.

Next, as shown in FIG. 11A, a flexible substrate 456 having conductive films 452a and 452b functioning as antennas and thin film integrated circuits 442a and 442b are used with anisotropic conductive adhesives 455a and 455b. And paste them together.
Note that the flexible substrate 456 including the conductive films 452a and 452b functioning as antennas is provided with openings so that parts of the conductive films 452a and 452b are exposed.
In addition, an insulating film 453 covering the conductive films 452a and 452b functioning as antennas is formed over the flexible substrate 456.

Therefore, the conductive films 452a and 452b functioning as antennas and the connection terminals of the thin film integrated circuits 442a and 442b are connected to the conductive particles 454a and 454b included in the anisotropic conductive adhesives 455a and 455b. , Paste together while aligning.
Here, the conductive film 452a functioning as an antenna and the thin film integrated circuit 442a are connected by the conductive particles 454a in the anisotropic conductive adhesive 455a, and the conductive film 452b functioning as an antenna and the thin film integrated circuit 442b are They are connected by conductive particles 454b in the anisotropic conductive adhesive 455b.

Next, as illustrated in FIG. 11B, the insulating film 453 and the flexible substrate 456 are separated in regions where the conductive films 452a and 452b functioning as antennas and the thin film integrated circuits 442a and 442b are not formed.
Here, the insulating film 453 and the flexible substrate 456 are divided by a laser cut method in which laser light 461 is irradiated.
Through the above steps, as illustrated in FIG. 11C, semiconductor devices 462a and 462b that can transmit data without contact can be manufactured.

Note that in FIG. 11A, a flexible substrate 456 including conductive films 452a and 452b functioning as antennas and thin film integrated circuits 442a and 442b are attached to each other with anisotropic conductive adhesives 455a and 455b. After that, a flexible substrate 463 is provided so as to seal the flexible substrate 456 and the thin film integrated circuits 442a and 442b. As shown in FIG. 11B, conductive films 452a and 452b functioning as antennas and thin films A semiconductor device 464 as illustrated in FIG. 11D may be manufactured by irradiation with a laser beam 461 in a region where the integrated circuits 442a and 442b are not formed.
In this case, since the thin film integrated circuit is sealed by the divided flexible substrates 456 and 463, deterioration of the thin film integrated circuit can be suppressed.

Through the above process, a thin and lightweight semiconductor device can be manufactured with high yield.
In addition, since the crystal plane orientation of the semiconductor layer of the thin film transistor of the semiconductor device can be aligned in a certain direction, variation in electrical characteristics of the thin film transistor can be suppressed.
For this reason, a highly reliable semiconductor device can be manufactured.

Next, a structure of the semiconductor device capable of transmitting data without contact will be described with reference to FIG.
The semiconductor device according to the fourth embodiment is roughly composed of an antenna unit 2001, a power supply unit 2002, and a logic unit 2003.
The antenna unit 2001 includes an antenna 2011 for receiving an external signal and transmitting data, and a signal transmission method in the semiconductor device can use an electromagnetic coupling method, an electromagnetic induction method, a microwave method, or the like. .
Note that the transmission method may be appropriately selected by the practitioner in consideration of the intended use, and an optimal antenna may be provided according to the transmission method.

The power supply unit 2002 includes a rectifier circuit 2021 that generates power based on a signal received from the outside via the antenna 2011, a storage capacitor 2022 that stores the generated power supply, and a constant voltage circuit 2023.
The logic unit 2003 generates a demodulation signal 2031 for demodulating the received signal, a clock generation / correction circuit 2032 for generating a clock signal, a code recognition / determination circuit 2033, and a signal for reading data from the memory based on the received signal. The memory controller 2034 includes a modulation circuit 2035 for putting the encoded signal on the reception signal, an encoding circuit 2037 for encoding the read data, and a mask ROM 2038 for holding the data.
Note that the modulation circuit 2035 includes a modulation resistor 2036.

The codes recognized and determined by the code recognition and determination circuit 2033 are a frame end signal (EOF: end of frame), a frame start signal (SOF), a flag, a command code, a mask length (mask length), and a mask value. (Mask value) and the like.
The code recognition and determination circuit 2033 also includes a cyclic redundancy check (CRC) function for identifying a transmission error.

Next, an application of the semiconductor device capable of transmitting data without contact will be described with reference to FIGS.
Although the semiconductor device 9210 capable of transmitting data without contact is widely used, for example, banknotes, coins, securities, bearer bonds, certificates (driver's license, resident's card, etc., FIG. 13A) Reference), packaging containers (wrapping paper, bottles, etc., see FIG. 13C), recording media (DVD software, video tape, etc., see FIG. 13B), vehicles (bicycles, etc., FIG. 13D) )), Personal items (such as bags and glasses), foods, plants, animals, human bodies, clothing, daily necessities, electronic devices, etc. and luggage tags (FIGS. 13E and 13F) ))) And the like can be used.

The semiconductor device 9210 of the fourth embodiment is fixed to an article by being mounted on a printed board, pasted on the surface, or embedded.
For example, a book is embedded in paper, and a package made of an organic resin is embedded in the organic resin, and is fixed to each article.
Since the semiconductor device 9210 of this embodiment realizes small size, thinness, and light weight, the design of the article itself is not impaired even after being fixed to the article.

Further, by providing the semiconductor device 9210 of the fourth embodiment on bills, coins, securities, bearer bonds, certificates, etc., an authentication function can be provided. Can be prevented.
In addition, by providing the semiconductor device of this embodiment in packaging containers, recording media, personal items, foods, clothing, daily necessities, electronic devices, etc., it is possible to improve the efficiency of systems such as inspection systems. it can.

[Embodiment 5]
As electronic devices including the semiconductor device described in any of Embodiments 2 to 4, a television device (also simply referred to as a television or a television receiver), a digital camera, a digital video camera, a mobile phone device (simply a mobile phone or a mobile phone) (Also called a telephone), portable information terminals such as PDAs, portable game machines, computer monitors, computers, sound reproduction apparatuses such as car audio, and image reproduction apparatuses equipped with recording media such as home game machines. .
A specific example thereof will be described as a fifth embodiment with reference to FIG.

A portable information terminal illustrated in FIG. 14A includes a main body 9201, a display portion 9202, and the like. By applying the display portion 9202 to that described in Embodiments 2 and 3, high-definition display can be performed. A possible portable information terminal can be provided at low cost.
A digital video camera shown in FIG. 14B includes a display portion 9701, a display portion 9702, and the like. By applying the display portion 9701 to the display portions in Embodiment Modes 2 and 3, high-definition display can be performed. Can be provided at low cost.
A portable terminal illustrated in FIG. 14C includes a main body 9101, a display portion 9102, and the like, and by applying the display portion 9102 to the one described in Embodiments 2 and 3, a highly reliable portable terminal Can be provided at low cost.

A portable television device shown in FIG. 14D includes a main body 9301, a display portion 9302, and the like. By applying any of the display modes described in Embodiments 2 and 3 to the display portion 9302, a portable television device capable of high-definition display can be provided at low cost.
Such a television device can be widely applied from a small one mounted on a portable terminal such as a cellular phone to a medium-sized one that can be carried and a large one (for example, 40 inches or more). .

A portable computer shown in FIG. 14E includes a main body 9401, a display portion 9402, and the like. By applying the display portion 9402 to those described in Embodiments 2 and 3, high image quality can be obtained. A portable computer capable of display can be provided at low cost.
A television device illustrated in FIG. 14F includes a main body 9501, a display portion 9502, and the like. By applying the display portion 9502 to any of Embodiments 2 and 3, high-definition display can be performed. A possible television device can be provided at low cost.

Here, the configuration of the television device will be described with reference to FIG. 15. FIG. 15 is a block diagram showing the main configuration of the television device.
The tuner 9511 receives a video signal and an audio signal. The video signal includes a video detection circuit 9512 and a video signal processing circuit 9513 that converts a signal output from the video signal into a color signal corresponding to each color of red, green, and blue. The video signal is processed by the control circuit 9514 for converting the input signal into the input specification of the driver IC.

The control circuit 9514 outputs signals to the scanning line driving circuit 9516 and the signal line driving circuit 9517 of the display panel 9515. In the case of digital driving, a signal dividing circuit 9518 is provided on the signal line side, and input digital A configuration may be employed in which the signal is divided into m and supplied.
Of the signals received by the tuner 9511, the audio signal is sent to the audio detection circuit 9521, and the output is supplied to the speaker 9523 through the audio signal processing circuit 9522.
The control circuit 9524 receives control information on the receiving station (reception frequency) and volume from the input unit 9525 and sends a signal to the tuner 9511 and the audio signal processing circuit 9522.

By including a display panel 9515 in this television device, the power consumption of the television device can be reduced and a television device capable of high-definition display can be manufactured. is there.
Note that the present invention is not limited to a television receiver, and is applied to various uses as a display medium of a particularly large area such as a personal computer monitor, an information display board at a railway station or an airport, and an advertisement display board in a street. can do.

Next, a mobile phone will be described with reference to FIG. 16 as one embodiment of an electronic device on which the semiconductor device of the present invention is mounted.
The cellular phone includes housings 2700 and 2706, a panel 2701, a housing 2702, a printed wiring board 2703, operation buttons 2704, and a battery 2705 (see FIG. 16). The panel 2701 is incorporated in the housing 2702 so as to be detachable. Is fitted to the printed wiring board 2703.
The shape and dimensions of the housing 2702 are changed as appropriate in accordance with the electronic device in which the panel 2701 is incorporated.

A plurality of packaged semiconductor devices are mounted on the printed wiring board 2703, and the semiconductor device of the present invention can be used as one of them.
The plurality of semiconductor devices mounted on the printed wiring board 2703 have any one function of a controller, a central processing unit (CPU), a memory, a power supply circuit, a sound processing circuit, a transmission / reception circuit, and the like.

Panel 2701 is connected to printed wiring board 2703 through connection film 2708.
The panel 2701, the housing 2702, and the printed wiring board 2703 are housed in the housings 2700 and 2706 together with the operation buttons 2704 and the battery 2705, and the pixel region 2709 included in the panel 2701 has an opening provided in the housing 2700. It is arranged so that it can be seen from the window.

In the panel 2701, a pixel portion and some peripheral driver circuits (a driver circuit having a low operating frequency among a plurality of driver circuits) are integrally formed using a TFT on a substrate, and some peripheral driver circuits (a plurality of driver circuits) are formed. Among them, a drive circuit having a high operating frequency may be formed on the IC chip.
The IC chip may be mounted on the panel 2701 by COG (Chip On Glass), or the IC chip may be connected to a glass substrate by using TAB (Tape Automated Bonding) or a printed board.

Note that FIG. 17A illustrates an example of a structure of a panel in which some peripheral driver circuits are formed integrally with a pixel portion over a substrate and an IC chip on which other peripheral driver circuits are formed is mounted by COG or the like.
Note that the panel in FIG. 17A includes a substrate 3900, a signal line driver circuit 3901, a pixel portion 3902, a scan line driver circuit 3903, a scan line driver circuit 3904, an FPC 3905, an IC chip 3906, an IC chip 3907, and a sealing substrate 3908. And a sealant 3909.
With such a structure, the power consumption of the display device can be reduced, and the usage time by one charge of the mobile phone can be extended.
In addition, the cost of the mobile phone can be reduced.

In order to further reduce power consumption, a pixel portion is formed on a substrate using TFTs as shown in FIG. 17B, and all peripheral driver circuits are formed on an IC chip. You may mount in a display panel by COG (Chip On Glass).
Note that the display panel in FIG. 17B includes a substrate 3910, a signal line driver circuit 3911, a pixel portion 3912, a scan line driver circuit 3913, a scan line driver circuit 3914, an FPC 3915, an IC chip 3916, an IC chip 3917, and a sealing substrate. 3918 and a sealant 3919 are provided.

As described above, the semiconductor device of the present invention is characterized in that it is small, thin, and lightweight, and the limited space inside the housings 2700 and 2706 of the electronic device can be effectively used due to the above characteristics. .
In addition, cost reduction is possible and an electronic device including a highly reliable semiconductor device can be manufactured.

In the following, the present invention will be described in more detail based on examples, but it is needless to say that the present invention is not limited by these examples and is specified by the claims. It is.
In addition to the examples, a comparative example will be given to explain the method for producing the crystalline silicon film of the present invention and the crystallographic properties.

A method for manufacturing the crystalline silicon film of Example 1 will be described with reference to FIGS.
As already described with reference to FIG. 1 in Embodiment Mode 1, the base film (insulating film) 101, the amorphous semiconductor film 102, and the cap film 103 are formed over the substrate 100.
As shown in FIG. 1B, the amorphous semiconductor film 102 is irradiated with laser light 104 through the cap film 103 to crystallize the amorphous semiconductor film 102 to form a crystalline semiconductor film 105. did.
As the substrate 100, a glass substrate having a thickness of 0.7 mm manufactured by Cornings Inc. was used.
As the insulating film 101, a film in which a silicon nitride film containing oxygen and a silicon oxide film containing nitrogen were stacked was formed using a parallel plate type plasma CVD apparatus.

The film formation conditions at that time are as follows.
<Silicon nitride film containing oxygen>
・ Thickness 50nm
・ Gas type (flow rate)
SiH ₄ (10 sccm)
NH ₃ (100 sccm)
N ₂ O (20 sccm)
H ₂ (400 sccm)
・ Substrate temperature 300 ℃
・ Pressure 40Pa
・ RF frequency 27MHz
・ RF power 50W
・ Distance between electrodes 30mm
-Electrode area 615.75 cm ²

<Silicon oxide film containing nitrogen>
・ Thickness 100nm
・ Gas type (flow rate)
SiH ₄ (4 sccm)
N ₂ O (800sccm)
・ Substrate temperature 400 ℃
・ Pressure 40Pa
・ RF frequency 27MHz
・ RF power 50W
・ Distance between electrodes 15mm
-Electrode area 615.75 cm ²

As the amorphous semiconductor film 102, an amorphous silicon film was formed using a parallel plate type plasma CVD apparatus.
The conditions for forming the amorphous silicon film are as follows.
<Amorphous silicon film>
・ Thickness 66nm
・ Gas type (flow rate)
SiH ₄ (25 sccm)
H ₂ (150 sccm)
・ Substrate temperature 250 ℃
・ Pressure 66.7Pa
・ RF frequency 27MHz
・ RF power 50W
・ Distance between electrodes 25mm
-Electrode area 615.75 cm ²

After forming an amorphous semiconductor film under the above-described film forming conditions, it was heated in an electric furnace at 500 ° C. for 1 hour, and then heated at 550 ° C. for 4 hours.
This heat treatment is for removing hydrogen from the amorphous silicon film, and is performed to prevent hydrogen gas from being ejected from the amorphous silicon film when irradiated with a laser beam. .
After the heat treatment, hydrofluoric acid treatment for 70 seconds is performed to remove the oxide film formed on the surface of the amorphous semiconductor film 102, and then a silicon nitride film containing oxygen is formed on the amorphous semiconductor film 102 as the cap film 103 Was formed using a parallel plate type plasma CVD apparatus.

The film formation conditions at that time are as follows.
<Silicon nitride film containing oxygen>
・ Thickness 300nm
・ Gas type (flow rate)
SiH ₄ (10 sccm)
NH ₃ (100 sccm)
N ₂ O (20 sccm)
H ₂ (400 sccm)
・ Substrate temperature 300 ℃
・ Pressure 40Pa
・ RF frequency 27MHz
・ RF power 50W
・ Distance between electrodes 30mm
-Electrode area 615.75 cm ²

The compositions of the obtained insulating film 101 and cap film 103 are shown in Table 1.
Table 1 also shows the composition of a cap film of a comparative example, which will be described later, and the composition of the film listed in Table 1 is a value before the heat treatment or laser irradiation.
The composition ratio was measured using Rutherford Backscattering Spectroscopy (RBS) and Hydrogen Forward Scattering (HFS).
The measurement sensitivity is about ± 2%.

After the cap film 103 was formed, it was heated in an electric furnace at 500 ° C. for 1 hour.
This heat treatment is a process for extracting hydrogen from the silicon nitride film containing oxygen, which is a cap film. Hydrogen is ejected from the silicon nitride film containing oxygen when irradiated with a laser beam. This is to prevent this from happening.

The amorphous silicon film was crystallized by irradiating a laser beam through the cap film 103 with a laser irradiation apparatus to form a crystalline silicon film.
Although the laser irradiation apparatus used at that time has already been described in the first embodiment, an outline thereof is shown here again with reference to FIG.
As shown in FIG. 18, two laser oscillators 11a and 11b are provided, and a laser beam 12 obtained by synthesizing the laser beams 12a and 12b emitted from the laser oscillators 11a and 11b can be irradiated. .

The laser beam 12b emitted from the laser oscillator 11b passes through the wave plate 13 and changes the polarization direction. This is because the polarizer 14 combines two laser beams having different polarization directions.
After passing through the wave plate 13, the laser beam 12b is reflected by the mirror 212, is incident on the polarizer 14, the laser beam 12a and the laser beam 12b are combined by the polarizer 14, and the combined laser beam 12 is appropriate. The wave plate 13 and the polarizer 14 are adjusted so as to obtain energy.

The laser beam 12 synthesized by the polarizer 14 is reflected by a mirror 15 and passes through a cylindrical lens 16 and a cylindrical lens 17 so that the cross section is formed into a linear shape.
The cylindrical lens 16 acts in the length direction of the beam spot formed on the irradiation surface, and the cylindrical lens 17 acts in the width direction.

The laser irradiation apparatus includes a suction stage 19 that fixes the irradiated surface 18, and the suction stage 19 can be moved in the XY directions by a single-axis robot 20 for X-axis and a single-axis robot 21 for Y-axis.
As described above, the substrate 1 on which the insulating film 101, the amorphous semiconductor film 102, and the cap film 103 are formed is fixed to the adsorption stage 19, and the length direction of the linear laser beam is aligned with the Y-axis, The laser beam was irradiated while moving the substrate 1 along the width direction, that is, along the X axis.

In this example, the moving speed of the substrate was set to 35 cm / sec.
Further, two laser oscillators were irradiated with the second harmonic (wavelength 532 nm) using an LD-pumped YVO ₄ laser.
The intensity of the laser beam on the irradiated surface was 14 W, and the shape of the laser beam was a linear shape having a length of about 500 μm and a width of about 20 μm.

<Measurement of crystalline silicon film>
In order to confirm the position and size of the crystal grains of the crystalline silicon film and the crystal plane orientation, EBSP measurement was performed.
In order to perform the EBSP measurement, the cap film 103 is removed from the surface of the crystalline silicon film by etching.
In the EBSP measurement, the crystal plane orientation was measured from an EBSP image obtained by making an electron beam incident at an incident angle of 60 ° with respect to the surface of the crystalline silicon film.

The measurement area was 50 μm × 50 μm, the measurement pitch was 0.1 μm, and EBSP images were measured on three observation planes A to C orthogonal to each other as shown in FIG.
2 represent normal vectors of the observation planes A to C, respectively.
The observation surface A is a surface parallel to the surface of the substrate and corresponds to the upper surface of the crystalline silicon film. The observation surface C is a surface in which the normal vector c is parallel to the scanning direction of the laser beam. From the information from the two observation planes A to C, the plane orientation of the crystal film can be specified with high accuracy.

The results of analyzing the plane orientation of the crystalline silicon film (crystal axis orientation perpendicular to the observation plane) are shown in FIGS.
FIGS. 19A to 19C are orientation map images showing the distribution of plane orientations in a measurement area of 50 μm × 50 μm, and the length of one side of each map diagram is 50 μm.
FIG. 19D is an inverted pole figure of single crystal silicon, and the color scheme represents the direction.

In FIG. 19, since only the brightness is displayed because it is black and white, it is difficult to distinguish, but in color display, the observation plane A is strongly oriented in the <001> direction and the observation plane B is strongly oriented in the <301> direction. It was found that the observation surface C is strongly oriented in the <301> direction.
Furthermore, it was found from the shape and color of the patterns of FIGS. 19A to 19C that the crystalline silicon film of Example 1 was composed of domains extending long in a columnar shape.
In FIGS. 19A to 19C, the length of the domain is 5 to 50 μm, and a domain having a length of 50 μm or more was also observed.

20A to 20C are inverted pole figures showing the frequency distribution of the surface orientations on the observation surfaces A to C, and FIG. 20D is a scale showing the frequency.
Since FIG. 20 is also monochrome, it is difficult to discriminate because only brightness is displayed, but from the reverse pole figure of FIG. 20A, 14.0 times the state in which all orientations appear with the same probability on the observation plane A. It was found that the <001> orientation appears with the above frequency.
Further, from the inverted pole figure shown in FIG. 20B, the <301> orientation is closest to black on the observation plane B, specifically, the frequency is 4.8 times or more the state where all the orientations appear with the same probability. It turns out that <301> orientation appears.
Furthermore, from the inverted pole figure shown in FIG. 20C, the <301> orientation is closest to black on the observation plane C, and more specifically, the frequency is 4.8 times or more the state in which all orientations appear with the same probability. It turns out that <301> orientation appears.

In the inverted pole figures of FIGS. 20A to 20C, the orientation ratio is obtained for the orientation having a high appearance frequency, and the calculation results of the orientation ratio are shown in FIGS. 21A to 21C.
FIG. 21A shows the result of obtaining the orientation ratio on the observation surface A based on FIG.
In the inverse pole figure of FIG. 20 (a), the range of <001> angle fluctuation is determined to be within ± 10 °, and <001> angle fluctuation for all measurement points is within ± 10 °. The orientation ratio was determined by determining the ratio of the numbers.

The value obtained by determining the ratio of the points having a specific orientation among all the measurement points is the value of the Partition Fraction. Among the points having the specific orientation, the orientation of the measurement points having high orientation reliability with respect to all the measurement points The value obtained from the ratio is the value of Total Fraction.
From this result, it was found that in the observation plane A of the present invention, the <001> orientation occupies 71.2% within an angular fluctuation range of ± 10 °.

Similarly, FIGS. 21B and 21C are the results of obtaining the <301> orientation rate on the measurement surfaces B and C based on the inverse pole figures of FIGS. 20B and 20C. The range of <301> angle fluctuation is determined to be ± 10 °, and the orientation rate is obtained.
In the observation plane B and the observation plane C, it was found that the <301> orientation accounted for 71.1% and 73.9%.
In the observation planes B and C, the ratio of the plane orientation <301> is shown, but it may be the orientation ratio of the plane orientation <401>, <501>, and <601> close to the plane orientation <301>.

[Comparative example]
As a comparative example, a crystalline silicon film was formed by changing the material of the cap film 103.
In the comparative example, a silicon oxide film having a thickness of 500 nm was formed as a cap film 103 by a parallel plate type plasma CVD apparatus.
The film formation conditions for the insulating film 101 and the amorphous semiconductor film 102 are the same as those in the example, and the specific film formation conditions for the cap film 103 are as follows.

<Silicon oxide film>
・ Thickness 500nm
・ Gas type (flow rate)
SiH ₄ (4 sccm)
N ₂ O (800sccm)
・ Substrate temperature 400 ℃
・ Pressure 40Pa
・ RF frequency 60MHz
・ RF power 150W
・ Distance between electrodes 28mm

In this comparative example, the heat treatment for extracting hydrogen from the amorphous silicon film was performed in the same manner as in the example. However, since the hydrogen contained in the cap film 103 is small, the heat treatment for extracting hydrogen from the cap film 103 is not performed. It was.
Further, the intensity of the irradiated laser beam was 15 W, and the moving speed of the substrate was 35 cm / sec.
Other than that, a crystalline silicon film was formed in the same manner as in the example.
The obtained crystalline silicon film was subjected to EBSP measurement in the same manner as in the example.
In the comparative example, the measurement area is 100 μm × 50 μm. In this area, the measurement was performed for each lattice point having a pitch of 0.25 μm, but the observation surfaces A to C are the same as those in the first embodiment.

22 is an orientation map showing the orientations of the observation planes A to C, FIG. 23 is an inverted pole figure, and FIG. 24 is a result of calculating the orientation rate.
FIGS. 23A to 23C are reverse pole figures showing the frequency distribution of the surface orientations on the observation planes A to C shown in FIG. 22, and FIG. 23D shows the frequency of the surface orientations. It is a scale.
Similarly to FIG. 20, FIG. 23 also shows that the region closer to black has a higher proportion of crystals having a plane orientation.

From the inverted polar diagram shown in FIG. 23 (a), the <211> orientation is closer to black on the observation plane A, and specifically, <211> with a frequency of 3.9 times or more of the state in which all orientations appear with equal probability. > It was found that the direction appeared.
Further, from the inverted pole figure shown in FIG. 23B, the <111> orientation is closest to black on the observation plane B, specifically, the frequency is 9.7 times or more that the state in which all orientations appear with the same probability. It was found that the <111> orientation appears.

Also, from the inverted pole figure shown in FIG. 23C, the <101> orientation is closest to black on the observation plane C, and specifically, the frequency is 9.7 times or more the state where all orientations appear with the same probability. It was found that the <101> orientation appears.
In FIG. 24A, a colored region is a region showing a crystal whose <211> orientation angle fluctuation is within ± 10 °.
In addition, the colored area in FIG. 24B is an area indicating a crystal whose <111> orientation angle fluctuation is within ± 10 °, and the colored area in FIG. , <101> is a region showing a crystal whose angle fluctuation is within ± 10 °.

In the comparative example, as can be seen from FIG. 23, the observation planes A, B, and C are strongly oriented in the <211>, <111>, and <101> directions, respectively.
Further, as can be seen from FIG. 24, the orientation ratio of <211> on the observation plane A is 42.1%, the <111> orientation ratio on the observation plane B is 41.2%, and <101 on the observation plane C. The orientation ratio of> was 52.3%.
The plane orientation of the crystal is expressed as <101> by summarizing equivalent plane orientation groups such as [101], [011], and [110].

(Contrast between Example and Comparative Example)
Comparing the orientation map images of FIG. 19 and FIG. 22, it can be seen that both the example and the comparative example are composed of domains extending in a columnar shape, but the example has a larger crystal size (length, width). ) Was found to be very large.
Furthermore, Table 2 summarizes the calculation results of the orientation ratios of the observation surfaces A to C of the example and the comparative example shown in FIGS.

As can be seen from Table 2, it was found that the surface orientations with high appearance frequency were different between the examples and the comparative examples on each of the observation surfaces A to C.
In the example, it was found that the plane orientation was aligned at a very high ratio of 70% or more in one direction on all three observation planes.
In other words, it was found that a crystalline semiconductor that can be regarded as having crystal plane orientations aligned in one direction was formed in the crystallized region.

In this example, the orientation ratios of <301> and other plane orientations are shown in FIGS. 25 and 26 on the observation surfaces B and C of the sample shown in Example 1. FIG.
25A to 25D are orientation map images showing the distributions of the plane orientations <601>, <501>, <401>, and <301> in the measurement area of 50 μm × 50 μm on the observation surface B, respectively. The length of one side of each map diagram is 50 μm. The measurement pitch was 0.1 μm.
25A to 25D, crystalline silicon films having plane orientations of <601>, <501>, <401>, and <301> are formed in the colored portions, respectively.

In FIGS. 25 (E) to 25 (H), the colored region is a region indicating a crystal having <601>, <501>, <401>, and <301> orientation angle fluctuations within ± 10 °, respectively. 25 (E) to (H) show the results of obtaining the orientation ratio of the plane orientation. The orientation rate was determined by determining the ratio of the number of measurement points where the angle fluctuation was within ± 10 ° in each plane orientation.
The value obtained by determining the ratio of the points having a specific orientation among all the measurement points is the value of the Partition Fraction. Among the points having the specific orientation, the orientation of the measurement points having high orientation reliability with respect to all the measurement points The value obtained from the ratio is the value of Total Fraction.

Table 3 shows the orientation ratio in each plane orientation. In addition, the decimal part is rounded off.
It can be seen from Table 3 that the orientation ratios of the crystal plane orientations <601>, <501>, <401>, and <301> on the observation plane B are 60% or more.

26A to 26D show the distributions of the plane orientations <601>, <501>, <401>, and <301> in the measurement region of 50 μm × 50 μm of the observation surface C of the sample shown in Example 1, respectively. The orientation map image is shown, and the length of one side of each map image is 50 μm. The measurement pitch was 0.1 μm.
In FIGS. 26A to 26D, crystalline silicon films having plane orientations of <601>, <501>, <401>, and <301> are formed in the colored portions, respectively.

In FIGS. 26 (E) to (H), the colored region is a region indicating a crystal in which the angle fluctuations in the <601>, <501>, <401>, and <301> directions are within ± 10 °, respectively. FIGS. 26E to 26H show the results of calculating the orientation ratio of the plane orientation. The orientation rate was determined by determining the ratio of the number of measurement points where the angle fluctuation was within ± 10 ° in each plane orientation.
Table 4 shows the orientation ratio in each plane orientation. In addition, the decimal part is rounded off.

From Table 4, it can be seen that the orientation ratios of the plane orientations <601>, <501>, <401>, and <301> on the observation plane C are 60% or more.
From the above, it can be seen that on the observation surfaces B and C, the orientation ratio is 60% or more even in <601>, <501>, and <401> other than the plane orientation <301>.

  In this embodiment, the orientation ratio of the plane orientation of the crystalline silicon film when the crystalline silicon film is formed by changing the energy and scanning speed of the laser beam and the thickness of the cap film as compared with the first embodiment. Will be described with reference to FIGS. 27 and 28. FIG.

First, a method for manufacturing a crystalline silicon film of Example 3 will be described with reference to FIGS.
A film in which a silicon nitride film containing oxygen and a silicon oxide film containing nitrogen, which are insulating films 101, are stacked on a substrate similar to the substrate shown in Embodiment 1 under the same conditions as in Embodiment 1 is a parallel plate type. The film was formed with a plasma CVD apparatus. Next, an amorphous silicon film was formed as the amorphous semiconductor film 102 under the same conditions as in Example 1 using a parallel plate type plasma CVD apparatus.

Next, the substrate was heated at 500 ° C. for 1 hour in an electric furnace.
After the heat treatment, the oxide film formed on the surface of the amorphous semiconductor film 102 by heating was removed with hydrofluoric acid. The hydrofluoric acid treatment at this time was 90 seconds. After that, a silicon nitride film containing oxygen was formed as a cap film 103 on the amorphous semiconductor film 102 using a parallel plate plasma CVD apparatus.

The film formation conditions at that time are as follows. The film forming conditions other than the thickness are the same as in Example 1.
<Silicon nitride film containing oxygen>
・ Thickness 400nm
・ Gas type (flow rate)
SiH ₄ (10 sccm)
NH ₃ (100 sccm)
N ₂ O (20 sccm)
H ₂ (400 sccm)
・ Substrate temperature 300 ℃
・ Pressure 40Pa
・ RF frequency 27MHz
・ RF power 50W
・ Distance between electrodes 30mm
-Electrode area 615.75 cm ²

After the cap film 103 was formed, it was heated in an electric furnace at 600 ° C. for 4 hours.
This heat treatment is a process for extracting hydrogen from the silicon nitride film containing oxygen, which is a cap film. Hydrogen is ejected from the silicon nitride film containing oxygen when irradiated with a laser beam. This can be omitted if the cap film contains less hydrogen.

The amorphous silicon film was crystallized by irradiating a laser beam through the cap film 103 with a laser irradiation apparatus to form a crystalline silicon film.
In this example, the moving speed of the substrate was 20 cm / sec.
Further, two laser oscillators were irradiated with the second harmonic (wavelength 532 nm) using an LD-pumped YVO ⁴ laser.
The intensity of the laser beam on the irradiated surface was 8.4 W, and the shape of the laser beam was a linear shape having a length of about 500 μm and a width of about 20 μm.

<Measurement of crystalline silicon film>
In order to confirm the position and size of the crystal grains of the crystalline silicon film and the crystal plane orientation, EBSP measurement was performed.
In order to perform the EBSP measurement, the cap film 103 is removed from the surface of the crystalline silicon film by etching.
In the EBSP measurement, an electron beam was incident on the surface of the crystalline silicon film at an incident angle of 60 ° to obtain an EBSP image. The crystal plane orientation was measured from the obtained EBSP image.
The measurement area was 50 μm × 50 μm, the measurement pitch was 0.5 μm, and as shown in FIG. 2, EBSP images were measured on three observation planes A to C orthogonal to each other.

FIGS. 27 to 30 show the results of analyzing the plane orientation of the crystalline silicon film (the crystal axis orientation perpendicular to the observation plane).
FIG. 27 shows the calculation result of the orientation rate when the orientation rate is obtained for the surface orientation having a high appearance frequency in the inverted pole figure (not shown) representing the appearance frequency distribution of the surface orientation on the observation surface A. Note that the colored region is a region showing a crystal whose angle fluctuation of the plane orientation <101> is within ± 10 °.
From FIG. 27, it was found that, in the observation plane A of this example, the <001> orientation was 80% within the range of the angle fluctuation of ± 10 °, accounting for 60% or more.

  FIG. 28 shows the calculation result of the orientation ratio when the orientation ratio is obtained for the plane orientation having a high appearance frequency in the inverted pole figure (not shown) representing the appearance frequency distribution of the plane orientation on the observation plane B. In FIG. 28A, a colored region is a region indicating a crystal whose angle fluctuation is within ± 10 ° of a crystal whose plane orientation is <001>, and a crystal region whose surface orientation is <001>. In FIG. 28B, a colored region in FIG. 28B indicates a crystal whose angle fluctuation of the plane orientation <601> is within ± 10 °, and the plane orientation is <601>. FIG. 28C shows a crystal orientation ratio, and a colored region is a region showing a crystal whose angle fluctuation of the plane orientation <501> is within ± 10 °, and the plane orientation <501>. In FIG. 28D, a colored region is a region indicating a crystal whose angle fluctuation of the plane orientation <401> is within ± 10 °, and the plane orientation < 401> indicates the orientation ratio of the crystal, and in FIG. The region shown is a region showing a crystal whose surface orientation <301> has an angle fluctuation within ± 10 °, and shows the orientation ratio of the crystal whose surface orientation is <301>. In FIG. The painted region is a region showing a crystal whose surface orientation <201> has an angle fluctuation within ± 10 °, and shows the orientation rate of the crystal whose surface orientation is <201>. In FIG. The colored region is a region showing a crystal whose angle fluctuation of the plane orientation <101> is within ± 10 °, and shows the orientation ratio of the crystal having the plane orientation <101>. In addition, Table 5 shows the orientation ratio in each plane orientation. In addition, the decimal part is rounded off.

  FIG. 29 shows the calculation result of the orientation ratio when the orientation ratio is obtained for the orientation having a high appearance frequency in the inverted pole figure (not shown) representing the appearance frequency distribution of the plane orientation on the observation plane C. In FIG. 29A, a colored region is a region showing a crystal whose angle fluctuation of <001> orientation is within ± 10 °, and shows the orientation ratio of the crystal whose surface orientation is <001>. In FIG. 29B, a colored region is a region showing a crystal whose angle fluctuation of <601> orientation is within ± 10 °, and the orientation ratio of the crystal whose surface orientation is <601> is shown. In FIG. 29C, a colored region is a region indicating a crystal whose angle fluctuation of <501> orientation is within ± 10 °, and the orientation ratio of the crystal whose plane orientation is <501> In FIG. 29D, a colored region is a region indicating a crystal whose angle fluctuation of <401> orientation is within ± 10 °, and the orientation of the crystal whose plane orientation is <401> In FIG. 29E, the colored area is <30. 1> A region showing a crystal whose orientation angle fluctuation is within ± 10 °, showing the orientation ratio of the crystal whose surface orientation is <301>, and in FIG. 29 (F), the colored region is <201> is an area showing a crystal whose orientation angle fluctuation is within ± 10 °, shows the orientation ratio of the crystal whose plane orientation is <201>, and in FIG. , <101> is a region showing a crystal whose angle fluctuation is within ± 10 °, and shows the orientation rate of the crystal whose orientation is <101>. In addition, Table 6 shows the orientation ratio in each plane orientation. In addition, the decimal part is rounded off.

  The sum of the orientation ratios of the plane orientations <001>, <601>, <501>, <401>, <301>, <201>, and <101> shown in Table 5 is 218.3%. Further, the total orientation ratio of the plane orientations <001>, <601>, <501>, <401>, <301>, <201>, and <101> shown in Table 6 is 244.4%. <001>, <601>, <501>, <401>, <301>, <201>, and <101> are calculated as only the orientation ratio in any one of the surface orientations. The results are shown in FIG.

  Note that the overlapping portions of the surface orientations of <001>, <601>, <501>, <401>, <301>, <201>, and <101> are only the orientation ratios in any one of the surface orientations. <001>, <601>, <501>, <401>, <301>, <201>, and <101> The total sum of all orientation ratios as described above is <x01> (x = 0, 1, 2, 3, 4, 5, 6).

  30A is an orientation map image showing the distribution of the surface orientation <001> of the observation surface A in the measurement region of 50 μm × 50 μm, and FIG. 30B is the observation surface B in the measurement region of 50 μm × 50 μm. Is an orientation map image showing the distribution of surface orientations <001>, <601>, <501>, <401>, <301>, <201>, and <101>, and FIG. It is an azimuth | direction map image which shows distribution of surface orientation <001>, <601>, <501>, <401>, <301>, <201>, and <101> of the observation surface C in a measurement area | region of 50 micrometers. The length of one side of each map diagram is 50 μm.

  Although it is black and white and only the brightness is displayed, it is difficult to distinguish, but in FIG. 30A, a crystalline silicon film having a <001> plane orientation is formed in the colored portion. 30B and 30C, crystalline silicon having a plane orientation of <001>, <601>, <501>, <401>, <301>, <201>, and <101> in the colored portion. A film is formed. In particular, in the color display, it can be seen that the observation plane B and the observation plane C are strongly oriented in the <201> direction and the <301> direction, respectively.

  FIG. 30D shows the result of obtaining the orientation ratio of the crystal having the plane orientation <001> of the observation plane A, and the colored region has an angle fluctuation of <001> orientation within ± 10 °. This is a region showing a certain crystal.

  FIG. 30E shows the crystal orientation ratios of the surface orientations <001>, <601>, <501>, <401>, <301>, <201>, and <101> of the observation surface B. It is a result. The entire colored region is a region showing a crystal whose angle fluctuation of <x01> (x = 0, 1, 2, 3, 4, 5, 6) orientation is within ± 10 °. In addition, since it is black and white and only the brightness is displayed, it is difficult to distinguish, but the color of the area is changed for each value of x, and <001>, <601>, <501>, <401>, <301>. , <201>, and <101> regions corresponding to the plane orientations. Here, the overlapping portion of the plane orientation is excluded.

  FIG. 30F shows the results of obtaining the orientation ratios of the crystals having the plane orientation <001>, <601>, <501>, <401>, <301>, <201>, and <101> on the observation plane C. It is. The entire colored region is a region showing a crystal whose angle fluctuation of <x01> (x = 0, 1, 2, 3, 4, 5, 6) orientation is within ± 10 °. Similarly to FIG. 30E, the region corresponding to each surface orientation is divided for each value of x.

  Orientation rate in each plane orientation of the observation planes A to C, and <x01> (x = 0, 1, 2, 3, 4, 5, 6) orientation rate (that is, <001>, < 601>, <501>, <401>, <301>, <201>, and <101> orientation summation ratios) are shown in Table 7. In addition, the decimal part is rounded off.

From Table 7, it can be seen that the crystal orientation on the observation surface A is <001> orientation accounting for 60% or more within the range of ± 10 ° angular fluctuation. Further, it can be seen that <x01> (x = 0, 1, 2, 3, 4, 5, 6) on the observation surface B occupies 60% or more. Furthermore, it can be seen that <x01> (x = 0, 1, 2, 3, 4, 5, 6) on the observation surface C occupies 60% or more. Furthermore, it can be seen that in the observation planes B and C, the orientation ratio of <x01> (x = 0, 2, 3, 4, 5, 6) excluding the plane orientation where x is 1 accounts for 60% or more.

  In this example, the orientation ratio of the plane orientation of the crystalline silicon film when the crystalline silicon film is formed by changing the energy and scanning speed of the laser beam and the film thickness of the cap film as compared with Example 1. This will be described with reference to FIG.

First, a method for manufacturing a crystalline silicon film of Example 4 will be described with reference to FIGS.
A film in which a silicon nitride film containing oxygen and a silicon oxide film containing nitrogen, which are insulating films 101, are stacked on a substrate similar to the substrate shown in Embodiment 1 under the same conditions as in Embodiment 1 is a parallel plate type. The film was formed with a plasma CVD apparatus. Next, an amorphous silicon film was formed as the amorphous semiconductor film 102 under the same conditions as in Example 1 using a parallel plate type plasma CVD apparatus.
After the film formation, an amorphous semiconductor film was formed under the film formation conditions described above, and then heated in an electric furnace at 500 ° C. for 1 hour, and further heated at 550 ° C. for 4 hours.

  Next, the oxide film formed on the surface of the amorphous semiconductor film 102 by heating was removed with hydrofluoric acid. The hydrofluoric acid treatment at this time was 90 seconds. After that, an oxide film was formed on the amorphous semiconductor film 102 with an aqueous solution containing ozone, and then the oxide film was removed with hydrofluoric acid. This is to sufficiently remove impurities on the surface of the amorphous silicon film. The treatment time of the aqueous solution containing ozone at this time was 40 seconds, and the hydrofluoric acid treatment was 90 seconds. Next, a silicon nitride film containing oxygen was formed as a cap film 103 over the amorphous semiconductor film 102 using a parallel plate plasma CVD apparatus.

The film formation conditions at that time are as follows. The film forming conditions other than the thickness are the same as in Example 1.
<Silicon nitride film containing oxygen>
・ Thickness 400nm
・ Gas type (flow rate)
SiH ₄ (10 sccm)
NH ₃ (100 sccm)
N ₂ O (20 sccm)
H ₂ (400 sccm)
・ Substrate temperature 300 ℃
・ Pressure 40Pa
・ RF frequency 27MHz
・ RF power 50W
・ Distance between electrodes 30mm
-Electrode area 615.75 cm ²

After the cap film 103 was formed, it was heated in an electric furnace at 600 ° C. for 4 hours.
This heat treatment is a process for extracting hydrogen from the silicon nitride film containing oxygen, which is a cap film. Hydrogen is ejected from the silicon nitride film containing oxygen when irradiated with a laser beam. This is to prevent this from happening.

The amorphous silicon film was crystallized by irradiating a laser beam through the cap film 103 with a laser irradiation apparatus to form a crystalline silicon film.
In this example, the moving speed of the substrate was 10 cm / sec.
Further, two laser oscillators were irradiated with the second harmonic (wavelength 532 nm) using an LD-pumped YVO ₄ laser.
The intensity of the laser beam on the irradiated surface was 6.4 W, and the shape of the laser beam was a linear shape having a length of about 500 μm and a width of about 20 μm.

<Measurement of crystalline silicon film>
In order to confirm the position and size of the crystal grains of the crystalline silicon film and the crystal plane orientation, EBSP measurement was performed.
In order to perform the EBSP measurement, the cap film 103 is removed from the surface of the crystalline silicon film by etching.
In the EBSP measurement, an electron beam was incident on the surface of the crystalline silicon film at an incident angle of 60 °. The crystal plane orientation was measured from the obtained EBSP image.

The measurement area was 50 μm × 50 μm, the measurement pitch was 0.5 μm, and as shown in FIG. 2, EBSP images were measured on three observation planes A to C orthogonal to each other.
FIG. 31 shows the result of analyzing the plane orientation of the crystalline silicon film (the crystal axis orientation in the direction perpendicular to the observation plane).

  FIG. 31A is an orientation map image showing the distribution of the plane orientation <001> of the observation surface A in the measurement region of 50 μm × 50 μm, and FIG. 31B is the observation surface B in the measurement region of 50 μm × 50 μm. Is an orientation map image showing the distribution of <001>, <301>, <201>, and <101>, and FIG. 31 (C) shows the surface orientation of the observation surface C in the measurement region of 50 μm × 50 μm < It is an orientation map image showing the distribution of 001>, <301>, <201>, and <101>. The length of one side of each map image is 50 μm.

  Although it is black and white and only brightness is displayed, it is difficult to discriminate, but in FIG. 31A, a crystalline silicon film having a <001> plane orientation is formed in the colored portion. In FIGS. 31B and 31C, crystalline silicon films having <001>, <301>, <201>, and <101> plane orientations are formed in the colored portion. In particular, in the color display, it can be seen that each of the observation surface B and the observation surface C is strongly oriented in the <201> direction.

  FIG. 31D shows the result of obtaining the orientation rate of the crystal having the surface orientation <001> of the observation surface A. The colored region is a region showing a crystal whose angle fluctuation in the <001> orientation is within ± 10 °.

  FIG. 31E shows the result of obtaining the orientation ratios of crystals having the surface orientations <001>, <301>, <201>, and <101> on the observation surface B. The entire colored region is a region showing a crystal whose angle fluctuation of <x01> (x = 0, 1, 2, 3) plane orientation is within ± 10 °. In addition, although it is black and white and only the brightness is displayed, it is difficult to discriminate, but the color of the surface orientation is changed for each value of x, and <001>, <301>, <201>, <101> are used for each color. The area corresponding to the plane orientation is divided. Here, the overlapping portion of the plane orientation is excluded.

  FIG. 31F shows the result of obtaining the orientation ratios of crystals having the plane orientations <001>, <301>, <201>, and <101> on the observation plane C. The entire colored region is a region showing a crystal whose angle fluctuation in the <x01> (x = 0, 1, 2, 3) orientation is within ± 10 °. Similarly to FIG. 31E, the region corresponding to each plane orientation is divided for each value of x.

  The orientation rate in each plane orientation of the observation planes A to C, and the orientation rate of <x01> (x = 0, 1, 2, 3) in the plane orientations of the observation planes B and C (that is, <001 excluding overlapping portions) >, <301>, <201>, and <101> orientation summation). In addition, the decimal part is rounded off.

It can be seen from Table 8 that the crystal plane orientation on the observation plane A occupies 76% of the <001> orientation within 60% or more within the range of the angle fluctuation of ± 10 °. Furthermore, it can be seen that <x01> (x = 0, 1, 2, 3) on the observation surface B occupies 72% of 60% or more.
When the orientation ratio of <x01> (x = 0, 1, 2, 3, 4, 5, 6) on the observation surface B is obtained by the same calculation, it accounts for 60% or more of 79%.

Further, it can be seen that <x01> (x = 0, 1, 2, 3) on the observation plane C occupies 86% or more of 86%.
When the orientation ratio of <x01> (x = 0, 1, 2, 3, 4, 5, 6) on the observation surface C is obtained by the same calculation, it accounts for 88% of 60% or more.
That is, the orientation rate of <x01> (x = 0, 1, 2, 3) is 60% or more, and the orientation rate of <x01> (x = 0, 1, 2, 3, 4, 5, 6) is , <X01> (x = 0, 1, 2, 3).
Furthermore, it can be seen that in the observation planes B and C, the orientation ratio of <x01> (x = 0, 2, 3) excluding the plane orientation where x is 1 accounts for 60% or more.

  In this embodiment, the orientation of the crystal silicon film when the crystalline silicon film is formed by changing the energy and scanning speed of the laser beam, the cap film composition and the film thickness as compared with the first embodiment. The rate will be described with reference to FIG.

First, a method for manufacturing a crystalline silicon film of Example 5 will be described with reference to FIGS.
A film in which a silicon nitride film containing oxygen and a silicon oxide film containing nitrogen, which are the insulating films 101, were stacked over a substrate 100 similar to the substrate shown in Example 1 was formed using a parallel plate type plasma CVD apparatus. .
In addition, the substrate 100 in that case used the glass substrate with a thickness of 0.7 mm made from Cornings.

The film formation conditions at that time are as follows.
<Silicon nitride film containing oxygen>
・ Thickness 50nm
・ Gas type (flow rate)
SiH ₄ (15 sccm)
NH ₃ (150 sccm)
N ₂ O (20 sccm)
H ₂ (1200 sccm)
・ Substrate temperature 330 ℃
・ Pressure 40Pa
・ RF frequency 13.56MHz
・ RF power 250W
・ Distance between electrodes 24.5mm
-Electrode area 2972.8 cm ²

<Silicon oxide film containing nitrogen>
・ Thickness 100nm
・ Gas type (flow rate)
SiH ₄ (30 sccm)
N ₂ O (1200 sccm)
・ Substrate temperature 330 ℃
・ Pressure 40Pa
・ RF frequency 13.56MHz
・ RF power 50W
・ Distance between electrodes 24.5mm
-Electrode area 2972.8 cm ²

Next, an amorphous silicon film was formed as the amorphous semiconductor film 102 using a parallel plate type plasma CVD apparatus.
The conditions for forming the amorphous silicon film are as follows.
<Amorphous silicon film>
・ Thickness 66nm
・ Gas type (flow rate)
SiH ₄ (280 sccm)
H ₂ (300 sccm)
・ Substrate temperature 330 ℃
・ Pressure 170Pa
・ RF frequency 13.56MHz
・ RF power 250W
・ Distance between electrodes 24.5mm
-Electrode area 2972.8 cm ²

Next, a silicon nitride film containing oxygen having a concentration lower than a measurement limit concentration in SIMS analysis was formed as a cap film 103 over the amorphous semiconductor film 102 using a parallel plate plasma CVD apparatus.
The film formation conditions at that time are as follows.
<Silicon nitride film containing oxygen below measurement limit concentration>
・ Thickness 300nm
・ Gas type (flow rate)
SiH ₄ (15 sccm)
NH ₃ (150 sccm)
H ₂ (1200 sccm)
・ Substrate temperature 330 ℃
・ Pressure 40Pa
・ RF frequency 13.56MHz
・ RF power 250W
・ Distance between electrodes 24.5mm
-Electrode area 2972.8 cm ²

The oxygen concentration in the formed cap film 103 is shown in FIG. The oxygen concentration of the film shown in FIG. 33 is a value before the heat treatment or laser irradiation.
The oxygen concentration was measured using secondary ion mass spectrometry (SIMS).
From FIG. 33, since the oxygen concentration of the cap film 103 of the fifth embodiment is almost below the measurement limit of the current SIMS analysis, it is actually lower (1 × 10 ¹⁷ atoms / cm ³ or less). Conceivable.

After the cap film 103 was formed, it was heated in an electric furnace at 500 ° C. for 1 hour and then at 550 ° C. for 4 hours.
This heat treatment is a process for extracting hydrogen from the silicon nitride film containing oxygen having a concentration less than the measurement limit concentration, which is a cap film. This is for preventing hydrogen gas from being ejected from the silicon nitride film containing silicon.

The amorphous silicon film was crystallized by irradiating a laser beam through the cap film 103 with a laser irradiation apparatus to form a crystalline silicon film.
In this example, the moving speed of the substrate was 20 cm / sec.
Further, two laser oscillators were irradiated with the second harmonic (wavelength 532 nm) using an LD-pumped YVO ₄ laser.
The intensity of the laser beam on the irradiated surface was 9.6 W, and the shape of the laser beam was a linear shape having a length of about 500 μm and a width of about 20 μm.

<Measurement of crystalline silicon film>
In order to confirm the position and size of the crystal grains of the crystalline silicon film and the crystal plane orientation, EBSP measurement was performed.
In order to perform the EBSP measurement, the cap film 103 is removed from the surface of the crystalline silicon film by etching.
In the EBSP measurement, the crystal plane orientation was measured from an EBSP image obtained by making an electron beam incident at an incident angle of 60 ° with respect to the surface of the crystalline silicon film.

The measurement area was 50 μm × 50 μm, the measurement pitch was 0.5 μm, and as shown in FIG. 2, EBSP images were measured on three observation planes A to C orthogonal to each other.
FIG. 32 shows the result of analyzing the plane orientation of the crystalline silicon film (the crystal axis orientation perpendicular to the observation plane).

  FIG. 32A is an orientation map image showing the distribution of the plane orientation <001> of the observation surface A in the measurement region of 50 μm × 50 μm, and FIG. 32B is the observation surface B in the measurement region of 50 μm × 50 μm. Is an orientation map image showing the distribution of <001>, <301>, <201>, and <101>, and FIG. 32 (C) shows the surface orientation of the observation surface C in the measurement region of 50 μm × 50 μm < It is an orientation map image showing the distribution of 001>, <301>, <201>, and <101>. The length of one side of each map image is 50 μm.

  In FIG. 32A, since only the brightness is displayed because it is monochrome, it is difficult to distinguish, but a crystalline silicon film having a <001> plane orientation is formed in the colored portion. In FIGS. 32B and 32C, crystalline silicon films having plane orientations of <001>, <301>, <201>, and <101> are formed in the colored portion. In particular, in the color display, it can be seen that the observation plane B and the observation plane C are strongly oriented in the <001> orientation.

  FIG. 32D shows the result of obtaining the orientation rate of the crystal having the plane orientation <001> of the observation plane A. In the colored region, the angle fluctuation of the <001> orientation is within ± 10 °. This is a region showing a certain crystal.

  FIG. 32E shows the result of obtaining the orientation ratios of crystals having the plane orientations <001>, <301>, <201>, and <101> on the observation plane B. The entire colored region is a region showing a crystal whose angle fluctuation in the <x01> (x = 0, 1, 2, 3) orientation is within ± 10 °. In addition, since it is black and white and it is difficult to discriminate because only the brightness is displayed, the color of the area is changed for each value of x, and <001>, <301>, <201>, and <101> are used for each color. The area corresponding to the plane orientation is divided. Here, the overlapping portion of the plane orientation is excluded.

FIG. 32 (F) shows the result of obtaining the orientation ratio of crystals having the plane orientations <001>, <301>, <201>, and <101> on the observation plane C. The entire colored region is a region showing a crystal whose angle fluctuation in the <x01> (x = 0, 1, 2, 3) orientation is within ± 10 °.
Similarly to FIG. 32E, the region corresponding to each surface orientation is divided for each value of x.

  The orientation rate in each plane orientation of the observation planes A to C, and the orientation rate of <x01> (x = 0, 1, 2, 3) in the plane orientations of the observation planes B and C (that is, <001 excluding overlapping portions) >, <301>, <201>, and <101> orientation summation). In addition, the decimal part is rounded off.

From Table 9, it can be seen that the crystal plane orientation on the observation plane A occupies 68% of the <001> orientation within 60% or more within the range of the angle fluctuation of ± 10 °. Further, it can be seen that <x01> (x = 0, 1, 2, 3) on the observation surface B occupies 72% of 60% or more.
When the orientation ratio of <x01> (x = 0, 1, 2, 3, 4, 5, 6) on the observation surface B is determined by the same calculation, it accounts for 81%, which is 60% or more.

Furthermore, it can be seen that <x01> (x = 0, 1, 2, 3) on the observation plane C occupies 81% of 60% or more.
When the orientation ratio of <x01> (x = 0, 1, 2, 3, 4, 5, 6) on the observation surface C is obtained by the same calculation, it occupies 85% of 60% or more.
That is, the orientation rate of <x01> (x = 0, 1, 2, 3) is 60% or more, and the orientation rate of <x01> (x = 0, 1, 2, 3, 4, 5, 6) is , <X01> (x = 0, 1, 2, 3).
Furthermore, it can be seen that in the observation planes B and C, the orientation ratio of <x01> (x = 0, 2, 3) excluding the plane orientation where x is 1 accounts for 60% or more.

FIG. 10 is a cross-sectional view illustrating a method for manufacturing a crystalline semiconductor film of the present invention. It is a perspective view explaining the surface orientation of the crystalline semiconductor film of this invention. 8A to 8D are cross-sectional views illustrating a method for manufacturing a semiconductor device of the present invention. 8A to 8D are cross-sectional views illustrating a method for manufacturing a semiconductor device of the present invention. 8A to 8D are cross-sectional views illustrating a method for manufacturing a semiconductor device of the present invention. It is sectional drawing explaining the structure of the light emitting element which can be applied to this invention. It is a figure explaining the equivalent circuit of the light emitting element which can be applied to this invention. 8A to 8D are cross-sectional views illustrating a method for manufacturing a semiconductor device of the present invention. 8A to 8D are cross-sectional views illustrating a method for manufacturing a semiconductor device of the present invention. 8A to 8D are cross-sectional views illustrating a method for manufacturing a semiconductor device of the present invention. 8A to 8D are cross-sectional views illustrating a method for manufacturing a semiconductor device of the present invention. It is a figure explaining the structure of the semiconductor device of this invention. It is a figure explaining the use of the semiconductor device of this invention. FIG. 11 illustrates an electronic device using a semiconductor device of the present invention. FIG. 11 illustrates a structure of an electronic device using a semiconductor device of the invention. FIG. 11 is a development view illustrating an electronic device using the semiconductor device of the present invention. It is a top view illustrating a semiconductor device of the present invention. It is a figure which shows the outline | summary of the laser irradiation apparatus applicable to this invention. It is an orientation map figure of the crystalline silicon film of an example obtained by EBSP measurement. It is a reverse pole figure of the crystalline silicon film of an Example obtained by EBSP measurement. It is a figure which shows the orientation rate of the crystalline silicon film of an Example obtained by the reverse pole figure. It is an orientation map figure of the crystalline silicon film of a comparative example obtained by EBSP measurement. It is a reverse pole figure of the crystalline silicon film of the comparative example obtained by EBSP measurement. It is a figure which shows the orientation rate of the crystalline silicon film of the comparative example obtained by the reverse pole figure. It is a figure which shows the orientation map figure and orientation rate of the crystalline silicon film of an Example obtained by EBSP measurement. It is a figure which shows the orientation map figure and orientation rate of the crystalline silicon film of an Example obtained by EBSP measurement. It is a figure which shows the orientation rate of the crystalline silicon film of an Example obtained by EBSP measurement. It is a figure which shows the orientation rate of the crystalline silicon film of an Example obtained by EBSP measurement. It is a figure which shows the orientation rate of the crystalline silicon film of an Example obtained by EBSP measurement. It is a figure which shows the orientation map figure and orientation rate of the crystalline silicon film of an Example obtained by EBSP measurement. It is a figure which shows the orientation map figure and orientation rate of the crystalline silicon film of an Example obtained by EBSP measurement. It is a figure which shows the orientation map figure and orientation rate of the crystalline silicon film of an Example obtained by EBSP measurement. It is a figure which shows the oxygen concentration of the cap film of an Example obtained by SIMS measurement.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Substrate 101 Insulating film 102 Amorphous semiconductor film 103 Cap film 104 Laser beam 105 Crystalline semiconductor film

Claims (7)

A semiconductor film having a plurality of crystal grains on a substrate,
In the first surface of the semiconductor film, the crystal plane orientation is within the range of ± 10 ° angular fluctuation, and the <001> orientation is 60% or more and less than 100%,
In the second surface of the semiconductor film, the crystal plane orientation is <001>, <101>, <201>, <301>, <401>, <501> or within an angular fluctuation range of ± 10 °. Any orientation of <601> is 60% or more and less than 100%,
In the third plane of the semiconductor film, the crystal plane orientation is <001>, <101>, <201>, <301>, <401>, <501> or within a range of ± 10 ° angular fluctuation. Any orientation of <601> is 60% or more and less than 100%,
The first surface of the semiconductor film is a surface in which a direction perpendicular to the surface of the substrate is a first direction, and the first direction is a normal vector,
The second surface of the semiconductor film is a surface parallel to the surface of the substrate and a direction parallel to the crystal growth direction as a second direction, and the second direction is a normal vector,
Said third surface of said semiconductor layer is parallel to the surface of the substrate, and the direction perpendicular to the third direction to the crystal growth direction, Ri said third plane der which direction is the normal vector of ,
The crystalline semiconductor film according to claim 1, wherein the crystal grains of the semiconductor film have a width of 0.1 to 10 μm and a length of 5 to 50 μm . A semiconductor film having a plurality of crystal grains on a substrate,
In the first surface of the semiconductor film, the crystal plane orientation is within the range of ± 10 ° angular fluctuation, and the <001> orientation is 60% or more and less than 100%,
In the second plane of the semiconductor film, the crystal plane orientation is 6 in the range of <x01> (x = 0, 1, 2, 3, 4, 5, 6) within an angular fluctuation range of ± 10 °. More than 100%,
In the third plane of the semiconductor film, the plane orientation of the crystal is 6 in the range of <x01> (x = 0, 1, 2, 3, 4, 5, 6) within an angular fluctuation range of ± 10 °. More than 100%,
The first surface of the semiconductor film is a surface in which a direction perpendicular to the surface of the substrate is a first direction, and the first direction is a normal vector,
The second surface of the semiconductor film is a surface parallel to the surface of the substrate and a direction parallel to the crystal growth direction as a second direction, and the second direction is a normal vector,
Said third surface of said semiconductor layer is parallel to the surface of the substrate, and the direction perpendicular to the third direction to the crystal growth direction, Ri said third plane der which direction is the normal vector of ,
The crystalline semiconductor film according to claim 1, wherein the crystal grains of the semiconductor film have a width of 0.1 to 10 μm and a length of 5 to 50 μm . The semiconductor film of the semiconductor is Si or Si _1-x Ge x crystalline semiconductor film according to claim 1 or 2 which is (0 <x <0.1). Wherein a has a semiconductor element comprising the crystalline semiconductor film according to any one of claims 1 to 3. An insulating film is formed on the substrate,
Forming an amorphous semiconductor film on the insulating film;
On the amorphous semiconductor film, a silicon nitride film having a thickness of 200 nm to 1000 nm, containing oxygen of 10 atomic% or less, and a composition ratio of nitrogen to silicon of 1.3 to 1.5 is formed.
By irradiating the amorphous semiconductor film with continuous-wave laser light transmitted through the silicon nitride film or laser light having a repetition frequency of 10 MHz or more to melt the amorphous semiconductor film and then crystallizing it, Forming crystal grains having a length of 0.1 to 10 μm and a length of 5 to 50 μm,
The crystallized semiconductor film has a first surface to a third surface;
In the first plane, the plane orientation of the crystal has a <001> orientation of 60% or more and less than 100% within an angular fluctuation range of ± 10 °.
In the second plane, the plane orientation of the crystal is <001>, <101>, <201>, <301>, <401>, <501> or <601> within the range of an angular fluctuation of ± 10 °. Any of the orientation is 60% or more and less than 100%,
In the third plane, the plane orientation of the crystal is <001>, <101>, <201>, <301>, <401>, <501>, or <601> within an angular fluctuation range of ± 10 °. Any of the orientation is 60% or more and less than 100%,
The first surface is a surface in which a direction perpendicular to the surface of the substrate is a first direction, and the first direction is a normal vector,
The second surface is a surface parallel to the surface of the substrate and a direction parallel to the crystal growth direction as a second direction, and the second direction is a normal vector,
The third surface is a surface parallel to the surface of the substrate and perpendicular to the crystal growth direction as a third direction, and the third direction is a normal vector. A method for manufacturing a crystalline semiconductor film. 6. The method for producing a crystalline semiconductor film according to claim 5 , wherein the silicon nitride film is formed by a plasma CVD method in an atmosphere containing SiH ₄ , NH ₃ and N ₂ O. 7. The method for manufacturing a crystalline semiconductor film according to claim 5, wherein the continuous wave laser beam or the laser beam having a repetition frequency of 10 MHz or more has a wavelength that is absorbed by the amorphous semiconductor film.