JP4763740B2 - Thin film semiconductor device and image display device using thin film semiconductor device - Google Patents

Description

  The present invention relates to a thin film semiconductor device having a polycrystalline semiconductor film, a method for manufacturing a polycrystalline semiconductor film, a manufacturing apparatus, and the like. The thin film semiconductor device of the present invention is useful for an image display device or the like.

  A conventional method for crystallizing an amorphous silicon thin film by scanning with a pulse laser will be described with reference to FIG. FIG. 7 is a diagram showing a conventional crystallization method using an excimer pulse laser. The amorphous silicon film 102 deposited on the substrate 100 through the base film 101 is irradiated with a laser beam 105 made of a linear excimer laser having a width L of about several millimeters on the substrate, and every 1 to several pulses. Next, the laser irradiation position is moved to crystallize the entire substrate. In this conventional method, crystal nuclei at the time of laser irradiation are randomly generated. Moreover, the average nucleation distance of the crystal nuclei is 0.5 microns or less under normal laser annealing conditions. Therefore, the grain size of the obtained polycrystalline silicon film 103 is 0.5 microns or less and the sizes are not uniform.

  Furthermore, the following method is disclosed in International Patent Publication WO9745827 (Patent Document 1). That is, when the width L of the laser beam 105 shown in FIG. 7 is shaped to 0.5 microns or less and the position of the laser beam 5 having this shape is moved every 0.5 microns or less, a pulse is irradiated. Then, the crystal grain formed first is grown as a seed in one direction. The one direction is a lateral direction, that is, a direction perpendicular to the growth film thickness.

International patent publication, WO9745827

  In the above conventional method, the time required for crystal growth is 100 nanoseconds or less, so that the crystal grain size obtained is 1 micron or less, and the variation in grain size is large. Moreover, the grain orientation was disordered, the defect density was large, and the roughness of the film surface was also large. Therefore, it is impossible to grow polycrystalline silicon having a large grain size, or to accurately control the grain size and grain boundary position. For this reason, the grain boundary is randomly included in the channel. Therefore, it has been difficult to improve TFT device characteristics, reliability, and uniformity between devices.

  On the other hand, the technique disclosed in the above-mentioned international patent publication, WO9745827 requires the beam to be converged to 1 micron or less, and thus the laser energy is lost and the optical system of the irradiation laser becomes complicated. Further, since the moving distance between laser pulses is 1 micron or less, it takes a long time to crystallize the entire substrate, and it is difficult to achieve high throughput and low cost. In particular, this method is not applicable to large area substrates. Furthermore, the movement of a minute distance is easily affected by vibration, and there is a problem in the yield.

  The first object of the present invention is to provide a high-quality polycrystal which can control grain boundaries, grain sizes, and crystal orientations on an insulating substrate such as glass, and reduce film roughness and crystal defects caused by the assumption of crystallization. An object of the present invention is to provide a manufacturing method, a manufacturing apparatus, and a thin film semiconductor device to which the polycrystalline semiconductor film is applied.

  A second object of the present invention is to reduce the number of manufacturing steps, to be easily applied to a large area substrate, to have a high throughput, a low cost, and to produce a high-quality polycrystalline semiconductor film, a manufacturing apparatus, and the polycrystalline semiconductor film. It is an object of the present invention to provide a thin film semiconductor device adapted to the above.

  A third object of the present invention is a manufacturing method and a manufacturing method for forming a high-quality polycrystalline semiconductor film that operates on a low-cost insulating substrate such as glass with high performance and high reliability and excellent uniformity between devices. An object of the present invention is to provide a device and a thin film semiconductor device adapted to the polycrystalline semiconductor film.

  The main forms of the present invention will be listed.

  According to a first aspect of the present invention, there is provided an insulating substrate, a first semiconductor film made of a polycrystalline semiconductor film, a gate electrode formed on the first semiconductor film via a gate insulating film, and the first semiconductor film. A first charge transmitting / receiving unit and a second charge transmitting / receiving unit provided in the semiconductor film at a predetermined interval, and a channel region formed between the first and second charge transmitting / receiving units, and The thin film semiconductor device is characterized in that a main orientation of the first semiconductor film constituting the channel region with respect to a main surface of the insulating substrate or the gate insulating film is {110}.

  By selecting the main orientation of the semiconductor film in the channel region with respect to the main surface of the insulating substrate or the gate insulating film, a highly reliable thin film semiconductor device can be provided even if a polycrystalline semiconductor film is used. A method for controlling the main orientation of the polycrystalline film will be described later.

Further, the MIS type thin film semiconductor device according to the present application can take the following various forms, for example.
(1) A mode in which a gate electrode is disposed on a predetermined polycrystalline semiconductor film via a gate insulating film.
(2) A mode in which a gate electrode is disposed below the predetermined polycrystalline semiconductor film via a gate insulating film.
(3) A mode in which a gate electrode is disposed on a side of a predetermined polycrystalline semiconductor film via a gate insulating film.

  According to a second aspect of the present invention, there is provided an insulating substrate, a first semiconductor film made of a polycrystalline semiconductor film, a gate electrode formed on the first semiconductor film via a gate insulating film, and the first semiconductor film. A first charge transmitting / receiving unit and a second charge transmitting / receiving unit provided in the semiconductor film at a predetermined interval, and a channel region formed between the first and second charge transmitting / receiving units, and The main orientation of the first semiconductor film constituting the channel region with respect to the main surface of the insulating substrate or the gate insulating film is {110}, and the first semiconductor film includes the first and second semiconductor films. In the thin film semiconductor device, the crystal grains in the longitudinal direction of the crystal grains of the channel region are mainly composed of 45 degrees or less with respect to the direction connecting the charge transmitting / receiving means. This form shows a more practical form of the present invention.

  In the thin film semiconductor device of the present invention, it is also useful that the first semiconductor film is composed of a low-angle grain boundary of 75 degrees or less with respect to the direction connecting the first and second charge transfer means. It is.

  According to a third aspect of the present invention, there is provided an insulating substrate, a first semiconductor film made of a polycrystalline semiconductor film, a gate electrode formed on the first semiconductor film via a gate insulating film, and the first semiconductor film. A first charge transmitting / receiving unit and a second charge transmitting / receiving unit provided in the semiconductor film at a predetermined interval, and a channel region formed between the first and second charge transmitting / receiving units, and The main orientation of the first semiconductor film constituting the channel region with respect to the main surface of the insulating substrate or the gate insulating film is {110}, and the channel region of the first semiconductor film is the first semiconductor film. A thin film semiconductor device having crystal grains connecting the charge transfer means and the second charge transfer means.

  The third form shows a more preferable form. That is, the channel region of the first semiconductor film is constituted by crystal grains having a length in the longitudinal direction enough to connect the first charge transmitting / receiving unit and the second charge transmitting / receiving unit, A highly reliable thin film semiconductor device can be provided.

  According to a fourth aspect of the present invention, there is provided an insulating substrate, a first semiconductor film made of a polycrystalline semiconductor film, a gate electrode formed on the first semiconductor film via a gate insulating film, and the first semiconductor film. A first charge transmitting / receiving unit and a second charge transmitting / receiving unit provided in the semiconductor film at a predetermined interval, and a channel region formed between the first and second charge transmitting / receiving units, and The main orientation of the first semiconductor film constituting the channel region with respect to the main surface of the insulating substrate or the gate insulating film is {110}, and the first semiconductor film includes the first and second semiconductor films. The thin film semiconductor device is characterized in that the main orientation of a plane substantially perpendicular to the direction connecting the charge transmitting / receiving means is {100}. The channel region of the first semiconductor film is composed of crystal grains having a length in a longitudinal direction enough to connect the first charge transmitting / receiving unit and the second charge transmitting / receiving unit, and the polycrystalline film By making the main orientation of {100}, a highly reliable thin film semiconductor device can be provided. In brief, the conclusion is that the first semiconductor film is polycrystalline, but if attention is paid to one crystal grain, it has properties equivalent to those of a single crystal.

  According to a fifth aspect of the present invention, an insulating substrate has at least two semiconductor device portions, and a second semiconductor layer and an insulating film layer are selectively formed in a partial region on the insulating substrate. The stacked body of the second semiconductor layer and the insulating film layer is in contact with the first semiconductor layer, and the second semiconductor layer is not provided between the first semiconductor device and the second semiconductor device. And a gate electrode formed on the first semiconductor film through a gate insulating film, a first charge transmitting / receiving unit and a second charge transmitting / receiving unit at predetermined intervals on the first semiconductor film, and the first And a channel region formed between the second charge transmitting / receiving means. Also in this embodiment, it is more preferable that the main orientation of the first semiconductor film constituting the channel region with respect to the main surface of the insulating amorphous substrate or the gate insulating film is {110}.

  This example is an example in which a second semiconductor layer is provided below a desired semiconductor device portion, and the semiconductor device portion has the first aspect of the present invention. Further, the present application is an example in which a second semiconductor layer is provided below a desired semiconductor device portion, and the semiconductor device portion is any one of the fourth to fourth embodiments of the present invention. Of course, it is good even if it has. Furthermore, it goes without saying that the present invention can be implemented by using various forms of the semiconductor device portion disclosed in this specification.

  According to a sixth aspect of the present invention, the insulating substrate has at least two semiconductor device portions, and is larger than the first thermal conductivity on the first thin film having the first thermal conductivity. A second thin film having a second thermal conductivity is selectively formed, and the second thin film is not in contact with the semiconductor layer, and is between the first semiconductor device portion and the second semiconductor device portion. The thin film semiconductor device is characterized in that the second thin film is disposed and the semiconductor device portion is constituted by the thin film semiconductor device according to any one of the first to fourth aspects.

  According to a seventh aspect of the present application, the semiconductor device has at least two semiconductor devices on an insulating substrate, and has a first thermal conductivity smaller than the first thermal conductivity on the first thin film having the first thermal conductivity. A second thin film having a thermal conductivity of 2 is selectively formed, the second thin film is in contact with the semiconductor layer, and the second thin film is interposed between the first semiconductor device and the second semiconductor device. No. 2 insulating layer is provided, and the semiconductor device portion is constituted by the thin film semiconductor device described in the first to fourth embodiments.

  Further, various practical forms will be described later.

  Next, main modes related to the semiconductor film manufacturing method according to the present invention will be listed. By using the following methods, a polycrystalline semiconductor film suitable for the purpose of the present application can be obtained.

  The eighth embodiment related to the polycrystalline semiconductor film manufacturing method of the present application is the step of generating crystal nuclei in the semiconductor layer on the insulating substrate, and the crystal grains are grown by melting and recrystallizing the semiconductor thin film by laser beam irradiation. A method of manufacturing a polycrystalline semiconductor film, wherein the process is performed separately.

  According to a ninth embodiment of the method for manufacturing a polycrystalline semiconductor film of the present invention, a crystal grain is grown by melting and recrystallizing a semiconductor thin film by laser beam irradiation on an amorphous semiconductor film on an insulating substrate. A method for manufacturing a polycrystalline semiconductor film according to the first embodiment.

  According to a tenth aspect of the method for manufacturing a polycrystalline semiconductor film of the present invention, the wavelength of the laser beam is selected from a range of 240 nm to 600 nm, and the absorption coefficient of the amorphous semiconductor film having the wavelength is a polycrystalline semiconductor film. 9. The method for producing a polycrystalline semiconductor film according to the eighth item, wherein the absorption coefficient is larger than the absorption coefficient of.

  According to an eleventh aspect of the method for manufacturing a polycrystalline semiconductor film of the present invention, the crystal nucleus of the polycrystalline silicon film on the insulating substrate is generated by melt recrystallization by laser irradiation. The method for producing a polycrystalline semiconductor film according to the eighth embodiment.

  It is preferable that the crystal nucleus of the polycrystalline silicon film on the insulating substrate according to the present invention is generated by a catalytic chemical deposition method.

  The manufacturing apparatus according to the present invention also includes means for modulating the pulse width of the laser beam, the time-dependent shape of the laser beam intensity, and the interval between the laser beams and pulses, and the laser beam emitted from the oscillation source. Means for shaping the profile of the irradiated region into a predetermined shape and then forming an image on the irradiated object; and means for moving the insulating substrate at a predetermined speed and pitch in synchronization with the irradiation of the laser beam. It is the manufacturing apparatus of the polycrystalline semiconductor thin film characterized by having having.

  In the present specification, the “charge transmitting / receiving means” usually means a region called a source or a drain.

  According to the present invention, a high-quality thin film semiconductor device can be realized on an amorphous substrate. Furthermore, the manufacturing method of the polycrystalline semiconductor thin film which can be used for this is provided. Furthermore, a manufacturing apparatus useful for such a manufacturing method is provided.

  Prior to the description of specific embodiments of the present invention, supplementary explanation will be given regarding typical embodiments of the present invention.

  In order to achieve the first and second objects of the present invention, the following means are useful.

  A region thicker than the channel region is provided in part of the drain or source region constituting the semiconductor layer. As a result, a very useful polycrystalline semiconductor film can be obtained.

  Further, the object can be easily achieved by the following means.

The pulse width of the laser beam is 100 ns or more and 1 ms or less, and the energy density is 200 mJ / cm ² or more and 10 J / cm ² or less. The intensity distribution of the laser beam is a distribution pattern in which the intensity within the beam width is uniform, or increases monotonously from one to the other and monotonously decreases.

  Furthermore, the third object is to provide a gate electrode provided on a first semiconductor layer made of a polycrystalline semiconductor film on an insulating substrate via a gate insulating film, a channel region provided in the semiconductor layer, In a MIS field effect transistor having a source region and a drain region disposed on both sides of a channel region, the main orientation of at least crystal grains constituting the channel region with respect to the surface of the substrate or the gate insulating film is {110}. Further, this can be achieved by adapting a semiconductor layer made of a polycrystalline semiconductor film having a main orientation of {100} in a plane substantially perpendicular to the direction connecting the source and drain regions to the channel of the semiconductor device.

  Furthermore, the object can be easily achieved by applying the following characteristics to the polycrystalline semiconductor film.

  The first is that a low-angle grain boundary of 75 degrees or less is formed between the source and drain regions of the channel region.

Second, the surface irregularity of the channel region is smaller than 20 nm, and the internal tensile stress of the channel region is 10 ⁹ dyn / cm ² or more.

Third, the metal element contained in the semiconductor layer is 10 ¹⁹ cm ⁻³ or less, and the crystal defect density contained in the channel region is 10 ¹⁷ cm ⁻³ or less.

  In the thin film semiconductor device of the present invention, the thin film semiconductor device is characterized in that the insulating substrate is a low melting point glass substrate. A typical example of the insulating substrate is an amorphous substrate, for example, a glass substrate, especially a low melting point glass substrate.

Furthermore, the various forms of the present invention are listed as follows.
(1) The thin film semiconductor device according to the present invention is characterized in that the surface of the insulating substrate in contact with the semiconductor layer has a height portion having a height of 10 nm or more. This is a practical form in which an insulating substrate such as a glass substrate has a height portion such as a swell of 10 nm or higher.
(2) In the thin film semiconductor device according to the present invention, the charge transmitting / receiving means constituting the semiconductor layer, that is, a drain region or a part of the source region has a region thicker than the channel region. Is a thin film semiconductor device.
(3) In the thin film semiconductor device according to the present invention, a thin film semiconductor having at least one protrusion having a width of 5 microns or less and a protrusion length of 5 microns or less at a peripheral portion in the same plane of the semiconductor layer. Device.

  In the thin film semiconductor device of the present invention, a mode in which the grain size of the semiconductor crystal in the channel region is larger than the grain size of the crystal grains in the charge transmitting / receiving means, that is, the source and drain regions is also practical.

With respect to the method of manufacturing the polycrystalline semiconductor thin film, the following forms can be given.
(4) In the method for manufacturing a polycrystalline semiconductor thin film according to the present invention, the pulse width of the irradiation laser beam is not less than 100 ns and not more than 1 ms.
(5) In the manufacturing method of forming a polycrystalline semiconductor film by irradiating an amorphous or polycrystalline semiconductor thin film formed on an insulating substrate with a laser beam to melt and recrystallize the semiconductor thin film, the laser beam Means for modulating the pulse width and time-dependent shape and interval of the laser beam, and shaping the irradiated region into a predetermined shape by an optical system comprising a plurality of lenses of the profile of the laser beam emitted from the oscillation source. A method for producing a polycrystalline semiconductor thin film, comprising: means for forming an image on the thin film; and means for moving the insulating substrate at a predetermined speed and pitch in synchronization with the irradiation of the laser beam. Method and manufacturing apparatus.
(6) In the method and apparatus for manufacturing a polycrystalline semiconductor thin film according to (5), the insulating substrate or the optical system is moved at a predetermined speed and interval in synchronization with the irradiation of the laser beam. A method and an apparatus for manufacturing a polycrystalline semiconductor film, comprising: means for detecting an alignment pattern on an insulating substrate; and means for aligning the laser beam with the substrate using an interferometer.
(7) In the method and apparatus for manufacturing a polycrystalline semiconductor thin film according to (5) or (6), the pulse width of the laser beam is 100 ns or more and 1 ms or less, and the energy density is 200 mJ / cm ² or more and 10 J / cm ² or less, the rise time of the laser beam, fall time, pulse width, pulse interval method and apparatus for manufacturing a polycrystalline semiconductor film, which is controlled by an external voltage by polarization by EO modulator It is.
(8) In the method and apparatus for manufacturing a polycrystalline semiconductor thin film, the intensity distribution of the laser beam is a distribution pattern in which the intensity within the beam width is uniform, or increases monotonously from one to the other, and decreases monotonously. A method for producing a polycrystalline semiconductor film.
(9) The laser device used for manufacturing the polycrystalline semiconductor thin film of the present invention is preferably a solid-state laser device or a semiconductor laser device.
(10) In the method and apparatus for manufacturing a polycrystalline semiconductor thin film, the intensity distribution of the laser beam has a light energy intensity gradient in a direction parallel to the source and rain directions. A manufacturing method and a manufacturing apparatus.

  Hereinafter, a thin film semiconductor device, a manufacturing method, and a manufacturing apparatus according to embodiments of the present invention will be described with reference to the drawings.

<Embodiment 1>
FIG. 1 is a diagram for explaining a thin film semiconductor device according to a first embodiment of the present invention. FIG. 1 shows an example having three polycrystalline silicon thin film transistors. 1A is a cross-sectional structure diagram, and FIG. 1B is a plan structure diagram. In FIGS. 1A and 1B, 100 is an insulating substrate, 101 is a lower layer film, 18 is a gate electrode, and 17 is a gate insulating film. As the insulating substrate, a glass substrate is often used. The lower layer film is usually a silicon dioxide (SiO ₂ ) film.

  Each silicon semiconductor layer includes a channel region 12, a source region 20, a drain region 19, and a projecting crystal nucleus region 30. The channel region 12 is made of a polycrystalline silicon film having a large grain size, and the crystal nucleus region 30 is usually made of a polycrystalline silicon film having a small grain size.

  In this example, as shown in the plan view of FIG. 1B, the gate electrodes 18 are connected in common. Of course, the present invention can also be implemented in a form in which a gate electrode is formed alone.

  The channel region 12 having a large particle diameter is obtained by a crystallization method as shown in FIG. An amorphous silicon film or polycrystalline silicon is irradiated with an inclined line-shaped laser beam having an intensity distribution as shown in FIG. In FIG. 1C, reference numeral 105 denotes an inclined shape, which shows a typical intensity distribution of the laser beam. The pulse width of the laser beam is preferably selected from the range of 100 nanoseconds or more and 1 millisecond or less. The optimum laser conditions for obtaining a particle diameter of, for example, 5 microns larger than the channel length when the thickness of the silicon semiconductor layer is 300 nm or less are, for example, a pulse width of 10 microseconds and a power of 1 w. When the laser beam is irradiated under such conditions, crystallization starts from the crystal nucleus region 30 in which the thickness of the silicon film is thicker than the surroundings. That is, crystal growth proceeds from a low temperature region. Crystal growth occurs in the direction of the arrow shown in FIG. 1C, and a polycrystalline silicon film 31 having a grain size larger than that of the channel region is formed.

  FIG. 3 is a cross-sectional view showing a manufacturing process of the thin film semiconductor device of this example. An underlayer of the silicon dioxide film 101 and further an amorphous silicon film or a polycrystalline silicon film 110 are formed on an amorphous substrate 100 such as glass (FIG. 3A). This amorphous silicon film or polycrystalline silicon film 110 is processed into three regions by etching using a usual photoresist. At this time, a crystal nucleus region 30 is formed (FIG. 3B). The substrate prepared in this state is irradiated with the laser light having the above-described tilted emission intensity ((c) in FIG. 3). In this case, the laser light is adjusted so as to have each inclined emission intensity according to the region of each semiconductor device. After melting and recrystallization of the semiconductor thin film, the gate insulating film 17 and the gate electrode 18 are formed (FIG. 3D). The source and drain are formed by usual ion implantation. As impurities, phosphorus, boron and the like are frequently used. (FIG. 3 (e)).

  In the present embodiment, after the polycrystalline silicon film including the crystal nucleus region 30 is formed on the insulating substrate, the semiconductor thin film is melted and recrystallized by laser beam irradiation to grow grains from the crystal nucleus. Can be carried out. The wavelength of the laser beam suitable for selectively growing crystal grains with high efficiency is preferably selected from the range of 240 nm to 600 nm. This is because, for example, the absorption coefficient of an amorphous silicon film at a wavelength of 500 nm is about five times larger than the absorption coefficient of a polycrystalline silicon film. Therefore, it is easy to selectively melt and recrystallize other semiconductor layer regions using a crystal nucleus made of a polycrystalline silicon film as a seed. On the other hand, a crystal nucleus region made of a polycrystalline silicon film having a small grain size on an insulating substrate can be generated by melt recrystallization by usual excimer pulse laser irradiation.

  FIG. 2 schematically shows the crystalline state of the semiconductor layer, particularly the channel region. 2A is a cross-sectional view of one transistor portion, and FIG. 2B is a schematic perspective view of a semiconductor layer. The corresponding areas in FIGS. 2A and 2B are associated with dotted lines. The meaning of each symbol is the same as in FIG. This example illustrates the most preferred example of the present invention.

  The main orientation of the polycrystalline body at least in the channel region 12 is {110} with respect to the surface of the gate insulating film and the substrate. The polycrystalline body is composed of a polycrystalline silicon film having a main orientation of {100} in a plane substantially perpendicular to the direction connecting the source region 20 and the drain region 19. Further, a plurality of crystal grains constituting the channel region 12 are composed of small-angle grain boundaries having a rotation angle of 70 degrees or less.

Furthermore, the surface irregularities of the channel region 12 are smaller than 20 nm, the internal tensile stress is 10 ⁹ dyn / cm ² or more, and the included crystal defect density is 10 ¹⁷ cm ⁻³ or less. Further, the metal element contained in the entire semiconductor layer including the channel region 12 is 10 ¹⁹ cm ⁻³ or less.

  FIG. 4 shows an example of a manufacturing apparatus used for carrying out the present invention. In this apparatus, an amorphous or polycrystalline semiconductor thin film formed on an insulating substrate 205 as shown in FIG. 2 is irradiated with a laser beam to melt and recrystallize the semiconductor thin film to form a polycrystalline semiconductor film. Suitable for forming. In this example, the CW laser device 200, the modulation means (201, 202, 203) for modulating the pulse width and time-dependent shape and interval of the laser beam, the optical system for imaging the laser beam from the oscillation source, the laser beam And a moving means that enables relative movement of the position of the irradiated object. The modulation means includes an EO modulator 201, a polarizing plate 202, and a driver 203. The optical system includes a beam shaping unit 204 for shaping the profile of a laser beam emitted from an oscillation source into an appropriate shape by an optical system comprising a plurality of lenses or a diffractive optical element, a mirror 208 with a scanning function, a laser beam. An imaging lens system 207 that forms an image. The moving means can move the insulating substrate 205 at a predetermined pitch in synchronization with the irradiation of the laser beam.

  Examples of the pulse width, time-dependent shape, and pulse interval of the laser beam are shown in FIGS. 5 (a) and 5 (b). FIG. 5A shows a voltage waveform applied to the EO modulator 201, and FIG. 5B shows a beam intensity waveform via the polarizer. The beam intensity can control the rise time, pulse width, fall time, pulse interval, and the like by an external voltage. Each of FIGS. 5A and 5B shows two examples of pulses having different pulse widths for controlling the pulse and an example of a gradient type pulse.

  6A and 6B show examples of the shape of the laser beam. In each perspective view, the laser beam is shaped into a desired shape by the beam shaping unit 204, and the shape of the beam imaged on the sample via the imaging lens. FIG. 6A shows a distribution pattern in which the intensity increases monotonously from one to the other, and FIG. 6B shows an example in which the intensity is uniform within the beam width. When manufacturing the thin film semiconductor device according to the present application, large crystal grains can be obtained efficiently when the width direction of the laser beam and the intensity distribution of the laser beam are parallel to the source and rain directions.

  A desired region can be crystallized by moving the insulating substrate 206 or the mirror 208 at a predetermined speed and interval in synchronization with the irradiation of the laser beam.

  In the present invention, the alignment pattern on the insulating substrate can be detected by, for example, a step in the semiconductor layer film or a step in the crystal nucleus region 30 in FIG. Specifically, the laser beam can be aligned with the substrate by an interferometer.

  This implementation forms a high-quality polycrystalline semiconductor film on an insulating substrate such as glass, which can control grain boundaries, grain size, and crystal orientation, and reduce film roughness and crystal defects caused by the assumption of crystallization. I was able to. Further, according to this embodiment, a manufacturing method and a manufacturing apparatus capable of forming a high-quality polycrystalline semiconductor film with a reduced number of manufacturing steps, easy application to a large-area substrate, high throughput, and low cost have been realized.

Further, when the polycrystalline semiconductor film described in this embodiment is applied to a MIS field effect transistor, the field effect mobility is about 300 cm ² / V · s or more, and the threshold voltage variation is suppressed to ± 0.2 V or less. can do. Thus, according to the present invention, it is possible to obtain a thin film semiconductor device that operates with high performance and high reliability and excellent uniformity between devices.

  In this embodiment, a polycrystalline silicon film is used as the semiconductor film before laser irradiation, but the same effect can be obtained even if an amorphous silicon film is used. In this embodiment, an inclined laser beam is used, but the same effect can be obtained even when a uniform beam is used. Further, in this embodiment, the crystal is grown from the crystal nucleus region 30 as a starting point. However, by optimizing the shape of the laser beam, the same effect can be obtained even in a structure that does not include the crystal nucleus 30 on the protrusion. . In this case, the initial semiconductor film is a polycrystalline silicon film containing crystal nuclei, and this film can be obtained by melt recrystallization by irradiation with an excimer laser or the like. Further, the same effect can be obtained even when the polycrystalline silicon film is formed at a low temperature by a CAT-CVD (Catalytic-Chemical Vapor Deposition) method.

<Embodiment 2>
FIG. 7 is a diagram for explaining the semiconductor device according to the second embodiment of the present invention. In this example, the second semiconductor layer is formed below the semiconductor layer constituting the channel from the viewpoint of crystal growth. The figure shows an example in which three polycrystalline silicon thin film transistors are mounted. 7A is a cross-sectional structure diagram, and FIG. 7B is a plan structure diagram. FIG. 7C is a cross-sectional view for explaining a laser beam irradiation method.

  7A and 7B, 100 is an insulating substrate, 101 is a lower layer film, 18 is a gate electrode, and 17 is a gate insulating film. As the insulating substrate, a glass substrate is often used. As the lower layer film, a silicon dioxide film is usually used.

  The first semiconductor layer has a channel region 12, a source region 20, and a drain region 19. The channel region 12 is made of a polycrystalline silicon film having a large grain size. A second semiconductor layer 41 is selectively inserted between the silicon semiconductor layer and the lower layer film 101 via the insulating film 40. On the other hand, the second semiconductor layer 41 is not provided in a region between the plurality of semiconductor devices.

  FIG. 8 is a cross-sectional view showing the manufacturing process of the thin film semiconductor device of this example. On the amorphous substrate 100 such as glass, a base layer of the silicon dioxide film 101, amorphous silicon as the second semiconductor layer 41, and a layer 40 of silicon dioxide are formed (FIG. 8A). The layers 40 and 41 are processed into three regions of a predetermined thin film semiconductor device by etching (FIG. 8B). Over this, an amorphous silicon film or a polycrystalline silicon film 110 is formed (FIG. 8C). The substrate prepared in this state is irradiated with the laser beam 105 having the above-described inclined emission intensity ((d) in FIG. 8). In this case, the laser light is adjusted so as to have each inclined emission intensity according to the region of each semiconductor device. In this example, a region where the second semiconductor film 40 does not exist becomes a crystal nucleus region. After melting and recrystallization of the first semiconductor thin film, the first semiconductor thin film is processed into a desired shape (FIG. 8E). A gate insulating film 17 and a gate electrode 18 are formed on the first semiconductor thin film. The source and drain are formed by a usual method (FIG. 8F).

  The channel region 12 having a large particle diameter is obtained by a crystallization method as shown in FIG. An amorphous silicon film or polycrystalline silicon is irradiated with an inclined line-shaped laser beam having an intensity distribution as shown in FIG. The laser pulse width is preferably selected from the range of 100 nanoseconds or more and 1 millisecond or less. The optimum laser conditions for obtaining a particle size of, for example, 5 microns larger than the channel length when the thickness of the silicon semiconductor layer is 100 nm or less are a pulse width of 10 microseconds and a power of 1 w.

  When the laser beam is irradiated under such conditions, crystallization is started from a region where the second silicon semiconductor layer is not provided below the silicon semiconductor layer. This is because the laser beam transmitted through the first silicon semiconductor film reaches the second silicon semiconductor film at the time of laser beam irradiation. In the second silicon semiconductor film, the laser beam is absorbed, and the temperature of the semiconductor layer rises. This temperature rise plays a role of a heat sink and can suppress rapid cooling. In a region where the heat sink is not provided under the first silicon semiconductor layer, the temperature is low and the crystallization start time is also fast. Therefore, crystallization starts from a region where the second semiconductor layer is not provided below the first silicon semiconductor layer, and becomes a crystal nucleus region 42. The wavelength of the laser beam suitable for selectively growing crystal grains with high efficiency is preferably selected from the range of 240 nm to 600 nm. In the present embodiment, after the polycrystalline silicon film including the crystal nucleus region 30 is formed on the insulating substrate, the semiconductor thin film is melted and recrystallized by laser beam irradiation to grow grains from the crystal nucleus. Can be performed separately. A crystal nucleus region made of a polycrystalline silicon film having a small grain size on an insulating substrate can be generated by melt recrystallization by excimer pulse laser irradiation, which is a conventional technique.

FIG. 2 shows the crystallinity of the semiconductor layer, particularly the channel region. At least the main orientation of the channel region 12 is {110} with respect to the surface of the gate insulating film, and the main orientation of a plane substantially perpendicular to the direction connecting the source region 20 and the drain region 19 is {100}. It is composed of a crystalline silicon film. Further, a plurality of crystal grains constituting the channel region 12 are composed of small-angle grain boundaries having a rotation angle of 75 degrees or less. Furthermore, the surface irregularities of the channel region 12 are smaller than 20 nm, the internal tensile stress is 10 ⁹ dyn / cm ² or more, and the included crystal defect density is 10 ¹⁷ cm ⁻³ or less. Further, the metal element contained in the entire semiconductor layer including the channel region 12 is 10 ¹⁹ cm ⁻³ or less.

  With respect to the manufacturing method and manufacturing apparatus for melting and recrystallizing a semiconductor thin film to form a polycrystalline semiconductor film, the same effect can be obtained by applying the one shown in FIG. 4 in the first embodiment. . In the present embodiment, the alignment pattern on the insulating substrate can be detected by the step between the second semiconductor layer film 41 and the insulating film 40 and the step of the crystal nucleus region 42 in FIG.

This implementation forms a high-quality polycrystalline semiconductor film on an insulating substrate such as glass, which can control grain boundaries, grain size, and crystal orientation, and reduce film roughness and crystal defects caused by the assumption of crystallization. I was able to. In addition, the present embodiment realized a manufacturing method and a manufacturing apparatus for forming a high-quality polycrystalline semiconductor film with a reduced number of manufacturing steps, easy application to a large area substrate, high throughput, and low cost. Furthermore, when the polycrystalline semiconductor film described in this embodiment is applied to a MIS field effect transistor, the field effect mobility is about 300 cm ² / V · s or more, and the threshold voltage variation is suppressed to ± 0.2 V or less. can do. According to this example, there is an effect that a semiconductor device that operates with high performance and high reliability and excellent uniformity between devices can be obtained.

<Embodiment 3>
FIG. 9 is a diagram for explaining the semiconductor device according to the third embodiment of the present invention. This example is an example using a member that partially facilitates heat release during crystal growth.

  The example of FIG. 9 shows an example in which three polycrystalline silicon thin film transistors are formed. 9A is a sectional structural view, and FIG. 9B is a plan structural view.

  9A and 9B, 100 is an insulating substrate, 101 is a lower layer film, 18 is a gate electrode, and 17 is a gate insulating film. The semiconductor layer is composed of a channel region 12, a source region 20, and a drain region 19, and the channel region 12 is made of a polycrystalline silicon film having a large grain size. An insulating film 50 is selectively provided on the lower layer film 101 between the plurality of semiconductor devices. The thermal conductivity of the insulating film 50 is larger than the thermal conductivity of the lower layer film 101 and the insulating substrate 100.

FIG. 10 is a cross-sectional view showing the manufacturing process of the thin film semiconductor device of this example. An Si ₃ N ₄ layer is formed on the amorphous substrate 100 such as glass as an insulating film 50 having a higher thermal conductivity than the underlying layer and the lower layer film 101 of the silicon dioxide film 101 (FIG. 10A). The insulating film 50 is processed corresponding to the region of each thin film semiconductor device. A region where the insulating film 50 is provided becomes a crystal nucleus region. An amorphous silicon film or a polycrystalline silicon film 110 is formed on the thus prepared substrate (FIG. 10B). The substrate prepared in this state is irradiated with the laser beam 105 having the above-described inclined emission intensity ((c) in FIG. 10). In this case, the laser light is adjusted so as to have each inclined emission intensity according to the region of each semiconductor device. After melting and recrystallization of the first semiconductor thin film, the first semiconductor thin film is processed into a desired shape (FIG. 10D). A gate insulating film 17 and a gate electrode 18 are formed on the first semiconductor thin film. A source and a drain are formed by a usual method (FIG. 10E).

  The channel region 12 having a large particle diameter is obtained by a crystallization method as shown in FIG. An amorphous silicon film or polycrystalline silicon is irradiated with an inclined line-shaped laser beam having an intensity distribution as shown in FIG. The laser pulse width is preferably selected from a range of 100 nanoseconds or more and 1 millisecond. The optimum laser conditions for obtaining a particle size of, for example, 5 microns larger than the channel length when the thickness of the silicon semiconductor layer is 100 nm or less are a pulse width of 10 microseconds and a power of 1 w. When the laser beam is irradiated under such conditions, crystallization starts from a region where the insulating film 50 is provided below in the silicon semiconductor layer. This is because, since the thermal conductivity of the insulating film 50 is higher than that of the lower layer film 101 and the insulating substrate 100, the semiconductor region in which the insulating film 50 is disposed below is compared with other semiconductor film regions. The amount of heat released downward increases, the temperature decreases quickly, and the crystallization start time is also early, so that it becomes a crystal nucleus region. In the present embodiment, after the polycrystalline silicon film including the crystal nucleus region 30 is formed on the insulating substrate, the semiconductor thin film is melted and recrystallized by laser beam irradiation to grow grains from the crystal nucleus. Can be carried out. A crystal nucleus region made of a polycrystalline silicon film having a small grain size on an insulating substrate can be generated by melt recrystallization by excimer pulse laser irradiation, which is a conventional technique. In the present embodiment, the insulating film 50 is processed into a rectangular shape, but the same effect can be obtained even if it is linear. A silicon nitride film or the like is suitable for the insulating film 50.

FIG. 2 shows the crystallinity of the semiconductor layer, particularly the channel region. At least the main orientation of the channel region 12 is {110} with respect to the surface of the gate insulating film, and the main orientation of a plane substantially perpendicular to the direction connecting the source region 20 and the drain region 19 is {100}. It is composed of a crystalline silicon film. Further, a plurality of crystal grains constituting the channel region 12 are composed of small-angle grain boundaries having a rotation angle of 70 degrees or less. Further, the surface irregularity of the channel region 12 is smaller than 20 nm, the internal tensile stress is 10 ⁹ dyn / cm ⁻² or more, the included crystal defect density is 10 ¹⁷ cm ⁻³ or less, and the entire semiconductor layer including the channel region 12 is formed. The metal element contained is 10 ¹⁹ cm ⁻³ or less.

  With respect to the manufacturing method and the manufacturing apparatus for forming a polycrystalline semiconductor film by melting and recrystallizing a semiconductor thin film, the same effect can be obtained by applying the one shown in FIG. 3 in the first embodiment. . In this embodiment, the alignment pattern on the insulating substrate can be detected by the step of the insulating film 51 in FIG.

This implementation forms a high-quality polycrystalline semiconductor film on an insulating substrate such as glass, which can control grain boundaries, grain size, and crystal orientation, and reduce film roughness and crystal defects caused by the assumption of crystallization. I was able to. In addition, the present embodiment realized a manufacturing method and a manufacturing apparatus for forming a high-quality polycrystalline semiconductor film with a reduced number of manufacturing steps, easy application to a large area substrate, high throughput, and low cost. Furthermore, when the polycrystalline semiconductor film described in this embodiment is applied to an MIS field effect transistor, the field effect mobility is about 300 cm ² / V · s or more, and the threshold voltage variation is suppressed to ± 0.2 V or less. Therefore, it is possible to obtain a semiconductor device that operates with high performance and high reliability and excellent uniformity between devices.

<Embodiment 4>
FIG. 11 is a diagram for explaining the semiconductor device according to the third embodiment of the present invention. (A) of three polycrystalline silicon thin film transistors is a cross-sectional structure diagram, and (b) is a plan structure diagram. In FIGS. 11A and 11B, 100 is an insulating substrate, 101 is a lower layer film, 51 is an insulating film, 18 is a gate electrode, and 17 is a gate insulating film. The semiconductor layer is composed of a channel region 12, a source region 20, and a drain region 19, and the channel region 12 is made of a polycrystalline silicon film having a large grain size. An insulating film 51 is selectively inserted between the silicon semiconductor layer and the lower layer film 101. The thermal conductivity of the insulating film 51 is smaller than the thermal conductivity of the lower layer film 101 and the insulating substrate 100.

  The channel region 12 having a large particle diameter is obtained by a crystallization method as shown in FIG. An amorphous silicon film or polycrystalline silicon is irradiated with an inclined line-shaped laser beam having an intensity distribution as shown in FIG. The laser pulse width is preferably selected from a range of 100 nanoseconds or more and 1 millisecond. The optimum laser conditions for obtaining a particle size of, for example, 5 microns larger than the channel length when the thickness of the silicon semiconductor layer is 100 nm or less are a pulse width of 10 microseconds and a power of 1 w. When the laser beam is irradiated under such conditions, crystallization starts in the void region in the silicon semiconductor layer where the insulating film 51 is not provided below. This is because, since the thermal conductivity of the insulating film 51 is higher than the thermal conductivity of the lower layer film 101 and the insulating substrate 100, the semiconductor region in which the insulating film 51 is disposed below is compared with other semiconductor film regions. The amount of heat released downward increases, the temperature decreases quickly, and the crystallization start time is also early, so that the crystal nucleus region 42 is obtained. In the present embodiment, after the polycrystalline silicon film including the crystal nucleus region 42 is formed on the insulating substrate, the semiconductor thin film is melted and recrystallized by laser beam irradiation to grow grains from the crystal nucleus. Can be carried out. A crystal nucleus region made of a polycrystalline silicon film having a small grain size on an insulating substrate can be generated by melt recrystallization by excimer pulse laser irradiation, which is a conventional technique. As the insulating film 51, an insulating film having a low density and a low dielectric constant, a porous silicon oxide film, or the like is suitable.

FIG. 2 shows the crystallinity of the semiconductor layer, particularly the channel region. At least the main orientation of the channel region 12 is {110} with respect to the surface of the gate insulating film, and the main orientation of a plane substantially perpendicular to the direction connecting the source region 20 and the drain region 19 is {100}. It is composed of a crystalline silicon film. Further, a plurality of crystal grains constituting the channel region 12 are composed of small-angle grain boundaries having a rotation angle of 70 degrees or less. Further, the surface irregularity of the channel region 12 is smaller than 20 nm, the internal tensile stress is 10 ⁹ dyn / cm ⁻² or more, the included crystal defect density is 10 ¹⁷ cm ⁻³ or less, and the entire semiconductor layer including the channel region 12 is formed. The metal element contained is 10 ¹⁹ cm ⁻³ or less.

  With respect to the manufacturing method and the manufacturing apparatus for forming a polycrystalline semiconductor film by melting and recrystallizing a semiconductor thin film, the same effect can be obtained by applying the one shown in FIG. 3 in the first embodiment. . In this embodiment, the alignment pattern on the insulating substrate can be detected by the step of the insulating film 50 in FIG.

This implementation forms a high-quality polycrystalline semiconductor film on an insulating substrate such as glass, which can control grain boundaries, grain size, and crystal orientation, and reduce film roughness and crystal defects caused by the assumption of crystallization. I was able to. In addition, the present embodiment realized a manufacturing method and a manufacturing apparatus for forming a high-quality polycrystalline semiconductor film with a reduced number of manufacturing steps, easy application to a large area substrate, high throughput, and low cost. Furthermore, when the polycrystalline semiconductor film described in this embodiment is applied to an MIS field effect transistor, the field effect mobility is about 300 cm ² / V · s or more, and the threshold voltage variation is suppressed to ± 0.2 V or less. Therefore, it is possible to obtain a semiconductor device that operates with high performance and high reliability and excellent uniformity between devices.

  According to the present invention, a high-quality polycrystalline semiconductor film that can control grain boundaries, grain sizes, and crystal orientations on an insulating substrate such as glass, and that reduces film roughness and crystal defects caused by the assumption of crystallization. There is an effect that a semiconductor device having the same can be obtained. In addition, there is an effect that a manufacturing method and a manufacturing apparatus for forming a high-quality polycrystalline semiconductor film with a reduced number of manufacturing steps, easy application to a large area substrate, high throughput, and low cost can be realized. Furthermore, a manufacturing method, a manufacturing apparatus, and the polycrystalline semiconductor film for forming a high-quality polycrystalline semiconductor film that operates with high performance and high reliability on an inexpensive insulating substrate such as glass and has excellent uniformity between devices. There is an effect that a semiconductor device adapted to the above can be obtained.

FIG. 1 is a diagram of a semiconductor device according to a first embodiment of the present invention. FIG. 2 is a diagram for explaining a semiconductor device according to the first embodiment of the present invention. FIG. 3 is a cross-sectional view shown in the order of steps for explaining a method of manufacturing a semiconductor device according to the present invention. FIG. 4 is a conceptual diagram of the configuration of the manufacturing apparatus of the present invention. FIG. 5 is a diagram showing examples of temporal changes in the intensity of the laser beam. FIG. 6 is a diagram showing an example of spatial distributions of laser beam intensities. FIG. 7 is a diagram for explaining a semiconductor device according to a second embodiment of the present invention. FIG. 8 is a cross-sectional view shown in the order of steps for explaining a method of manufacturing a semiconductor device according to the present invention. FIG. 9 is a diagram for explaining a semiconductor device according to a third embodiment of the present invention. FIG. 10 is a cross-sectional view shown in the order of steps for explaining a method of manufacturing a semiconductor device according to the present invention. FIG. 11 is a diagram for explaining a semiconductor device according to a fourth embodiment of the present invention. FIG. 12 is a perspective view showing an example of conventional laser beam irradiation.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Insulating substrate, 101 ... Underlayer film, 102 ... Amorphous silicon film, 103 ... Polycrystalline silicon film, 105 ... Laser beam, 10 ... Semiconductor layer, 12 ... Channel region, 17 ... ... Gate insulating film, 18 ... Gate electrode, 19 ... Drain region, 20 ... Source region, 30 ... Crystal nucleus region, 31 --- 40 ... Insulating film, 41 ... Semiconductor layer, 42 ... Crystal Nuclear region, 50, 51 ... Insulating film, 200 ... CW laser, 201 ... EO modulator, 202 ... Polarizer, 204 ... Beam shaping unit, 205 ... Substrate scanning unit, 206 ... Insulating substrate 207 ... imaging lens, 209 ... mirror, 207 ... imaging lens, 110 ... semiconductor layer.

Claims (8)

An insulating substrate, a first semiconductor film made of a polycrystalline semiconductor film, a gate electrode, a gate insulating film formed between the first semiconductor film and the gate electrode, and the first semiconductor film First charge transfer means and second charge transfer means provided at a predetermined interval; and a channel region formed in the first semiconductor film between the first and second charge transfer means; and the first semiconductor film constituting the channel region, the main alignment with respect to the surface of the insulating substrate or the gate insulating film is the {110}, the part of the previous SL charge transmitting and receiving means, said channel region The first semiconductor film has a region thicker than the thickness , the channel region has a surface irregularity of less than 20 nm, an internal tensile stress of 10 ⁹ dyn / cm ² or more, and a crystal defect density of 10 ¹⁷ cm ^-3 Is lower, and a thin film wherein a metal element density of ¹⁰ 19 ^{cm -3} or less.   2. The thin film semiconductor device according to claim 1, further comprising at least one protrusion having a width of 5 microns or less and a protrusion length of 5 microns or less as a region thicker than the channel region. An insulating substrate, a first semiconductor film made of a polycrystalline semiconductor film, a gate electrode, a gate insulating film formed between the first semiconductor film and the gate electrode, and the first semiconductor film First charge transfer means and second charge transfer means provided at a predetermined interval; and a channel region formed in the first semiconductor film between the first and second charge transfer means; The main orientation of the first semiconductor film constituting the channel region with respect to the surface of the insulating substrate or the gate insulating film is {110}, and the semiconductor film constituting the channel region is the first semiconductor film. In addition , the first semiconductor film is composed mainly of crystal grains in which the longitudinal axis of the crystal grains in the channel region is 45 degrees or less with respect to the direction connecting to the second charge transfer means. Surface roughness in the region is 20n Less than, and is at the internal tensile stress is ¹⁰ 9 dyn / cm ² or more, and said the crystal defect density is not more ¹⁰ 17 ^{cm -3} or less, and the metal element density of ¹⁰ 19 ^{cm -3} or less Thin film semiconductor device. An insulating substrate, a first semiconductor film made of a polycrystalline semiconductor film, a gate electrode, a gate insulating film formed between the first semiconductor film and the gate electrode, and the first semiconductor film First charge transfer means and second charge transfer means provided at a predetermined interval; and a channel region formed in the first semiconductor film between the first and second charge transfer means; The main orientation of the first semiconductor film constituting the channel region with respect to the surface of the insulating substrate or the gate insulating film is {110}, and the semiconductor film constituting the channel region is the first semiconductor film. And the first semiconductor film has a surface irregularity of less than 20 nm in the channel region. Yes, and internal tensile stress 10 ⁹ dyn / cm ² or more, and crystal defect density is not more ¹⁰ 17 ^{cm -3} or less, and a thin film wherein a metal element density of ¹⁰ 19 ^{cm -3} or less. Insulating substrate, first semiconductor film made of polycrystalline semiconductor film provided on insulating substrate, gate electrode, and gate insulating film formed between first semiconductor film and gate electrode And a first charge transfer means and a second charge transfer means provided in the first semiconductor film at predetermined intervals, and a first semiconductor film between the first and second charge transfer means. and a channel region, and said first semiconductor film constituting the channel region, a main orientation {110} with respect to the insulating substrate or the main surface of the gate insulating film, before Symbol charge handset A part of the means has a region thicker than the channel region , and the first semiconductor film has a surface irregularity of less than 20 nm in the channel region and an internal tensile stress of 10 ⁹ dyn / cm ^2. And the crystal Recessed density of the ¹⁰ 17 ^{cm -3} or less, and an image display device including a thin film semiconductor device, wherein the metal element density of ¹⁰ 19 ^{cm -3} or less.   6. The image display device including a thin film semiconductor device according to claim 5, wherein the region thicker than the channel region has at least one protrusion having a width of 5 microns or less and a protrusion length of 5 microns or less. An insulating substrate, a first semiconductor film made of a polycrystalline semiconductor film, a gate electrode, a gate insulating film formed between the first semiconductor film and the gate electrode, and the first semiconductor film First charge transfer means and second charge transfer means provided at a predetermined interval; and a channel region formed in the first semiconductor film between the first and second charge transfer means; The main orientation of the first semiconductor film constituting the channel region with respect to the surface of the insulating substrate or the gate insulating film is {110}, and the semiconductor film constituting the channel region is the first semiconductor film. In addition , the first semiconductor film is composed mainly of crystal grains whose longitudinal axis of the crystal grains in the channel region is 45 degrees or less with respect to the direction connecting with the second charge transmitting / receiving means. Surface irregularities in the area Characterized in that less than 0 nm and is in the internal tensile stress is ¹⁰ 9 dyn / cm ² or more and the crystal defect density is not more ¹⁰ 17 ^{cm -3} or less, and the metal element density of ¹⁰ 19 ^{cm -3} or less An image display device using a thin film semiconductor device. An insulating substrate, a first semiconductor film made of a polycrystalline semiconductor film, a gate electrode, a gate insulating film formed between the first semiconductor film and the gate electrode, and the first semiconductor film First charge transfer means and second charge transfer means provided at a predetermined interval; and a channel region formed in the first semiconductor film between the first and second charge transfer means; The main orientation of the first semiconductor film constituting the channel region with respect to the surface of the insulating substrate or the gate insulating film is {110}, and the semiconductor film constituting the channel region is the first semiconductor film. And the first semiconductor film has a surface irregularity of less than 20 nm in the channel region. Yes, and internal tensile stress 10 ⁹ dyn / cm ² or more, and crystal defect density is not more ¹⁰ 17 ^{cm -3} or less, and an image display using a thin film semiconductor device, wherein the metal element density of ¹⁰ 19 ^{cm -3} or less apparatus.

Images