JP4259081B2 - Manufacturing method of semiconductor device - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a method for manufacturing a semiconductor device including a semiconductor element such as a thin film transistor or a thin film element, and a semiconductor device manufactured using the manufacturing method, an electro-optical device, and an electronic apparatus.
[0002]
[Prior art]
In an electro-optical device such as a liquid crystal display device or an EL (electroluminescence) display device, pixels are switched using a thin film circuit including a semiconductor element such as a thin film transistor. In a conventional thin film transistor, an active region (channel formation region) is formed using an amorphous silicon film. A thin film transistor in which an active region is formed using a polycrystalline silicon film has also been put into practical use. By using a polycrystalline silicon film, electrical characteristics such as mobility are improved as compared with the case of using an amorphous silicon film, and the performance of the thin film transistor can be improved.
[0003]
In order to further improve the performance of the thin film transistor, a technique for forming a semiconductor film made of large crystal grains and preventing a crystal grain boundary from entering the formation region of the thin film transistor has been studied. For example, there are several techniques for forming silicon crystal grains of several μm by forming fine holes (fine holes) on a substrate and crystallizing a semiconductor film using the fine holes as a starting point for crystal growth. (Non-patent document 1 and non-patent document 2). By forming a thin film transistor using a silicon film containing large crystal grains formed using these techniques, a thin film transistor excellent in electrical characteristics such as mobility can be realized.
[0004]
[Non-Patent Document 1]
"Single Crystal Thin Film Transistors", IBM TECHNICAL DISCLOSURE BULLETIN Aug. 1993 pp257-258
[0005]
[Non-Patent Document 2]
`` Advanced Excimer-Laser Crystallization Techniques of Si Thin-Film For Location Control of Large Grain on Glass '', R.Ishihara et al., Proc.SPIE 2001, vol.4295, p.14-23
[0006]
[Problems to be solved by the invention]
In the conventional method described above, large crystal grains of about several μm can be formed, but the plane orientation of the obtained crystal grains is not controlled, and the plane orientation of each crystal grain is in a random state. It was. In order to further improve the electrical characteristics of the thin film transistor, it is desired to establish a manufacturing method capable of forming a semiconductor film by controlling the crystal plane orientation.
[0007]
Therefore, an object of the present invention is to provide a method for manufacturing a semiconductor device that enables a thin film element to be formed using a semiconductor film made of crystal grains whose surface orientation is controlled.
[0008]
Another object of the present invention is to provide a semiconductor device with good electrical characteristics.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, a manufacturing method of the present invention is a manufacturing method of a semiconductor device in which a semiconductor element is formed on an insulating substrate, a micro hole forming step for forming micro holes on the insulating substrate, and an insulating substrate. A semiconductor film forming step of forming a semiconductor film by depositing a semiconductor material on and in the micropores; and a crystallization promoting material made of a metal-containing substance and promoting crystallization of the semiconductor film from above the semiconductor film. A step of implanting a crystallization promoting material to be implanted from the opening to the bottom, a compound forming step of applying a first heat treatment to the semiconductor film to form a compound of the semiconductor film and the crystallization promoting material in the micropore, and a semiconductor film A melt crystallization step of forming a crystalline semiconductor film starting from the compound in the micropores by applying a second heat treatment to the crystallizing process.
[0010]
The semiconductor film was crystallized by heat treatment after forming a crystallization-promoting material comprising a metal-containing substance and a compound of the semiconductor film in the micropore as a starting point for crystallization of the semiconductor film. At this time, it is possible to form a semiconductor film (crystalline semiconductor film) in which the crystal grains are large and the plane orientation is controlled in a range having the fine hole as a substantial center. By forming a semiconductor element using a high-quality semiconductor film which can be regarded as a substantially single crystal state and whose plane orientation is controlled, it is possible to improve the performance of the semiconductor device.
[0011]
Here, in the present invention, “substantially single crystal” means not only a single crystal grain but also a state close to this, that is, the number of crystals combined is small, and the properties of the semiconductor thin film The case where it has the property equivalent to the semiconductor thin film formed from a single crystal from a viewpoint is also included.
[0012]
Moreover, it is preferable that the manufacturing method according to the present invention further includes an element forming step of forming a semiconductor element using a crystalline semiconductor film. Here, in the present invention, the “semiconductor element” includes various types of transistors, diodes, resistors, inductors, capacitors, and other elements that can be manufactured by a combination of N-type and P-type semiconductors, regardless of active elements / passive elements. Further, in the present invention, the “semiconductor device” is a device including the semiconductor element, for example, a device including an integrated circuit. By using the crystalline semiconductor film according to the present invention, a semiconductor element and a semiconductor device having excellent electrical characteristics can be obtained.
[0013]
Moreover, it is preferable to form the fine hole formed on the insulating substrate so that the ratio of the hole depth to the hole diameter is larger than 2.75. More preferably, the fine holes are formed so that the ratio of the depth of the holes to the hole diameter is larger than 5. More preferably, the fine holes may be formed so that the ratio of the hole depth to the hole diameter is larger than 11. By forming micropores under the above conditions, it becomes possible to preferentially align the crystal orientation of the crystal grains appearing above the micropores in a specific direction. When crystallizing a semiconductor film, the micropores The plane orientation of the semiconductor film can be adjusted on the basis of the plane orientation of the crystal grains appearing on the upper part.
[0014]
The diameter of the fine holes formed on the insulating substrate is desirably 45 nm or more and 190 nm or less. By forming micropores under these conditions, it is possible to more effectively obtain an action of preferentially growing one crystal nucleus in the micropore.
[0015]
The semiconductor film formed in the semiconductor film forming step preferably has a thickness of 30 nm to 100 nm. This makes it possible to make the crystallization progress in melt crystallization only in a direction substantially perpendicular to the film thickness direction of the semiconductor film, making it difficult for crystallization to proceed in other directions. Further homogenization can be achieved.
[0016]
Moreover, it is preferable that the semiconductor film formed in the semiconductor film forming step has silicon (silicon) as a main constituent element. As such a semiconductor film, for example, an amorphous or polycrystalline silicon film is preferably used. As a result, it is possible to form a high-quality silicon film having a substantially single crystal state and a controlled plane orientation within a range centered on the fine hole, and to form a semiconductor element using this high-quality silicon film. become.
[0017]
In the above-described crystallization promoting material driving step, it is preferable to perform driving so that the crystallization promoting material is concentrated in the vicinity of the bottom of the micropore. Thereby, it can avoid as much as possible that a crystallization promotion material is contained also in parts other than the bottom part of a micropore, ie, a part with a low necessity of supplying a crystal body promotion material.
[0018]
The crystallization promoting material described above is preferably a substance containing any of nickel, iron, cobalt, platinum, and palladium. The crystallization promoting material is preferably a silicon compound (silicide). By using such a crystallization promoting material, it becomes possible to effectively control the plane orientation of the crystal grains.
[0019]
Also, the implantation of the crystallization promoting material is performed when the semiconductor film thickness is 50 nm, the fine hole depth is 825 nm, and the crystallization promoting material is a nickel-containing material, the implantation energy is 1 MeV (megaelectron volts), the dose. 10 quantity ¹⁶ -10 ¹⁸ cm ^-2 It is preferable to carry out as According to this condition, the crystallization promoting material can be driven into an appropriate position.
[0020]
The first heat treatment described above is preferably performed at a temperature of 300 ° C. to 550 ° C. The reason why the lower limit of the heat treatment temperature is about 300 ° C. is that the semiconductor film and the compound of the crystallization promoting material are formed sufficiently and sufficiently. Moreover, the upper limit of the temperature of heat processing shall be about 550 degreeC for the following reasons. That is, when a semiconductor device used for an electro-optical device or the like is formed, an inexpensive glass substrate (for example, soda lime glass) is often used as an insulating substrate from the viewpoint of material cost. In this case, since the softening point of commonly used glass such as soda lime glass is about 550 ° C., it is added to the insulating substrate in order not to cause the insulating substrate to be softened by heat applied during manufacture. This is because the upper limit of the temperature needs to be about 550 ° C. corresponding to the softening point.
[0021]
The processing time t (second) in the first heat treatment is the processing temperature T (° C.) and the Boltzmann constant k. _B = 8.617 × 10 ^-5 eV ・ K ^-1 , Ε = 0.783 eV, t ₀ = 1.59 × 10 ^-3 (Seconds)
t ≧ t ₀ ・ Exp {ε / k _B (T + 273.16)},
It is better to set so as to satisfy the relationship. This makes it possible to accurately set the heat treatment time. Here, the “treatment temperature” basically indicates the substrate temperature of the insulating substrate to be heat-treated. However, for industrial convenience, the inside of a container such as a high-temperature furnace for applying heat to the insulating substrate. You may substitute with temperature. In this case, an experiment or the like is performed, and it is confirmed in advance how much time has passed since the insulating substrate was placed in a container having an atmospheric temperature T (° C.), and the substrate temperature becomes substantially the same as the atmospheric temperature. The measurement of the processing time t (second) obtained by the above calculation formula may be started from the time when the substrate temperature becomes approximately T (° C.) after the time has elapsed.
[0022]
The second heat treatment performed for melt crystallization of the semiconductor film is preferably performed by laser irradiation. Thereby, it becomes possible to perform heat processing efficiently. Various lasers such as an excimer laser, a solid-state laser, and a gas laser can be considered.
[0023]
The present invention is also a semiconductor device manufactured using the manufacturing method described above. Specifically, the semiconductor device of the present invention is a semiconductor device including a semiconductor element formed on an insulating substrate, and the semiconductor element spreads from the arrangement position of the semiconductor element and is melt-crystallized. The crystalline semiconductor film has a large crystal grain size corresponding to the element region, and the crystalline semiconductor film starts from a fine hole formed on the insulating substrate in accordance with the arrangement position of the semiconductor element. Crystallization is performed, and a crystallization promoting material made of a metal-containing substance and promoting crystallization of the semiconductor film is disposed at the bottom of the micropore.
[0024]
The above-described semiconductor device according to the present invention is particularly suitable for use in an electro-optical device. Specifically, an electro-optical device having good performance is provided by arranging the semiconductor device according to the present invention in a desired arrangement state (for example, in a matrix) and using the driving device for driving pixels as an electro-optical device. Can be obtained. By using such an electro-optical device, it is possible to configure a high-quality electronic device.
[0025]
Here, the “electro-optical device” means a general device including an electro-optical element that includes the semiconductor device according to the present invention and emits light by an electrical action or changes the state of light from the outside. Both those that emit light and those that control the transmission of light from the outside are included. For example, as an electro-optical element, a liquid crystal element, an electrophoretic element having a dispersion medium in which electrophoretic particles are dispersed, an EL (electroluminescence) element, and an electroluminescent element that emits light by applying electrons generated by applying an electric field to a light emitting plate. A display device provided.
[0026]
The “electronic device” means a general device having a certain function provided with the semiconductor device according to the present invention, and includes, for example, an electro-optical device and a memory. The configuration is not particularly limited, but for example, a mobile phone, a video camera, a personal computer, a head mounted display, a rear or front projector, a fax machine with a display function, a finder for a digital camera, a portable TV, a DSP device. , PDAs (portable information terminals), electronic notebooks, IC cards, electronic bulletin boards, advertising displays, and the like.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0028]
1 and 2 are explanatory views for explaining the method for manufacturing the semiconductor device of the present embodiment.
[0029]
(Micropore formation process)
As shown in FIG. 1A, a silicon oxide film 12 is formed on a substrate 10 made of an insulating material such as glass. Examples of the method for forming the silicon oxide film 12 include physical vapor deposition methods such as plasma chemical vapor deposition (PECVD), low pressure chemical vapor deposition (LPCVD), and sputtering. For example, the silicon oxide film 12 having a thickness of 100 nm can be formed by PECVD.
[0030]
Here, in the present embodiment, as shown in FIG. 1A, a silicon oxide film 12 formed on a glass substrate 10 corresponds to an “insulating substrate”. The silicon oxide film 12 is provided for the purpose of avoiding impurities (for example, alkali components) from flowing out of the glass substrate 10, and is essential in principle of the present invention. It is not a component. Therefore, when using a glass substrate having a very low impurity content, the substrate alone may be used as the “insulating substrate” without forming the silicon oxide film 12. Moreover, the material which comprises a board | substrate is not limited to glass.
[0031]
Next, as shown in FIG. 1B, fine holes 13 are formed in the silicon oxide film 12. The micro holes 13 are for preferentially growing only one crystal nucleus. In the following description, this fine hole is referred to as a “grain filter”. The grain filter 13 is formed, for example, by forming a photoresist film (not shown) having an opening that exposes the formation position of the grain filter 13 on the silicon oxide film 12 and using the photoresist film as a mask. It can be formed by performing ion etching and then removing the photoresist film on the silicon oxide film 12. The grain filter 13 is preferably formed in a cylindrical shape, but may have a shape other than the cylindrical shape (for example, a cone shape, a prism shape, a pyramid shape, etc.).
[0032]
Here, the pore diameter of the grain filter 13 is preferably 45 to 190 nm. Further, it is preferable that the grain filter 13 is formed so that the hole diameter is 1.5 to 1.9 times the thickness of a silicon film to be formed on the silicon oxide film 14 later. For example, in this embodiment, the film thickness of the silicon film is 50 nm, and the hole diameter of the grain filter 13 is 75 nm (= 50 nm × 1.5). In the present embodiment, the depth of the grain filter 13 is 825 nm. The reason why the dimension of the grain filter 13 is set to such a value will be described later.
[0033]
(Semiconductor film formation process)
Next, as shown in FIG. 1C, a semiconductor film containing silicon (silicon) as a main constituent element is formed on the silicon oxide film 12 and in the grain filter 13 by a film forming method such as LPCVD. In this embodiment, an amorphous (or polycrystalline) silicon film 14 is formed as a semiconductor film. The silicon film 14 is preferably formed to a thickness of about 30 to 100 nm.
[0034]
(Crystalline accelerating material driving process)
Next, as shown in FIG. 1D, a nickel element as a crystallization promoting material is implanted from the upper side of the silicon film 14 into the range from the opening to the bottom of the grain filter 13 by an ion implantation method. A nickel layer 16 is formed inside 12. This nickel element implantation is performed by appropriately setting the implantation conditions so that the nickel layer 16 formed in the silicon oxide film 12 is concentrated in the vicinity of the bottom of the grain filter 13. Specifically, when the film thickness d of the silicon film 14 is 50 nm, the hole diameter r of the grain filter 13 is 75 nm, and the depth h of the grain filter 13 is 875 nm, the condition for implanting the nickel element is the implantation energy. Is about 1 MeV, and the dose amount (additional impurity amount) is 10 ¹⁶ -10 ¹⁸ cm ^-2 Is preferable. By setting such a condition, it is possible to drive in such a way that the nickel density is highest in the vicinity of the bottom of the grain filter 13 and to concentrate the nickel element at this position. Note that it is also preferable to use an element such as iron, cobalt, platinum, palladium, or a silicon compound (silicide) as the crystallization promoting material instead of the nickel element.
[0035]
(Compound formation process)
Next, as shown in FIG. 2A, a heat treatment (first heat treatment) is applied to the substrate 10 on which the silicon oxide film 12 and the silicon film 14 are formed, and silicon and nickel in the grain filter 13 are applied. Compound NiSi ₂ Form. This heat treatment is preferably performed at a temperature of about 300 ° C to 550 ° C. The reason why the lower limit of the temperature of the heat treatment is about 300 ° C. is that a compound of silicon and nickel is necessary and sufficiently formed. Moreover, the upper limit of the temperature of heat processing shall be about 550 degreeC for the following reasons. That is, from the viewpoint of material cost and the like, an inexpensive glass substrate (for example, soda lime glass) is often used as the substrate 10. In this case, since the glass used generally has a softening point of about 550 ° C., the upper limit of the temperature applied to the substrate 10 is softened in order to prevent the substrate 10 from being softened by heat applied during manufacture. This is because the temperature needs to be lower than about 550 ° C. corresponding to the point. For the reasons described above, in the present embodiment, a range of 300 ° C. to 550 ° C. is adopted as a suitable temperature when performing the first heat treatment.
[0036]
In addition, with regard to the relationship between the treatment temperature and the treatment time during heat treatment, suitable conditions have been found by detailed examination by the inventors of the present application. The conditions will be described below. The processing time t (second) for performing the first heat treatment is the processing temperature T (° C.) and the Boltzmann constant k. _B = 8.617 × 10 ^-5 eV ・ K ^-1 , Ε = 0.783 eV, t ₀ = 1.59 × 10 ^-3 (Seconds)
t ≧ t ₀ ・ Exp {ε / k _B (T + 273.16)} (1),
It is better to set so as to satisfy the relationship.
[0037]
FIG. 3 is a graph (graph) showing the relationship between the treatment temperature T (° C.) and the treatment time t (seconds) during the heat treatment based on the above equation (1). For example, when the processing temperature is 300 ° C., it can be read from the graph that the processing time should be 12206 seconds (about 3 hours 23 minutes) or more. Similarly, when the processing temperature is 400 ° C., it can be read from the graph that the processing time should be 1158 seconds (about 19 minutes) or more. When the processing temperature is 500 ° C., it can be read from the graph that the processing time should be 202 seconds or more. When the processing temperature is set to 550 ° C., it can be read from the graph that the processing time should be 99 seconds or more. From the viewpoint of productivity and the like, it is practical to set the processing time to 30000 seconds (about 8 hours) or less. From such a point of view, it is preferable to set the heat treatment time t within a range shown by hatching in FIG.
[0038]
(Melt crystallization process)
Next, as shown in FIG. 2B, a heat treatment (second heat treatment) by laser irradiation is applied to the silicon film 14 to cause melt crystallization, and the crystalline semiconductor starts from the compound in the grain filter 13. A film is formed. As a result, as shown in FIG. 2C, a substantially single crystal silicon film 18 composed of large crystal grains centering on the grain filter 13 is formed. During the melt crystallization, the surface orientation of the silicon film 18 is substantially controlled in a specific direction by the action of the silicon and nickel compound formed in the grain filter 13 adjusting the crystal orientation. Is possible.
[0039]
In the second heat treatment described above, for example, an XeCl pulse excimer laser having a wavelength of 308 nm and a pulse width of 20 to 30 ns is used, and the energy density is 0.4 to 1.5 J / cm. ² It is preferable that the laser irradiation is performed so as to reach a degree. By performing laser irradiation under such conditions, most of the irradiated laser is absorbed near the surface of the silicon film 16. This is because the absorption coefficient of amorphous silicon at the wavelength (308 nm) of a XeCl pulse excimer laser is 0.139 nm. ^-1 This is because it is relatively large. By appropriately selecting the laser irradiation conditions in this manner, the silicon film 14 is left in the grain filter 13 so that the non-molten portion remains and the other portions are substantially completely melted. As a result, the crystal growth of silicon after the laser irradiation starts first near the bottom of the grain filter 13 and proceeds to the vicinity of the surface of the silicon film 14, that is, the substantially completely melted portion. Several crystal grains are generated at the bottom of the grain filter 13. At this time, by setting the cross-sectional dimension of the grain filter 13 (in this embodiment, the diameter of a circle) to be about the same as or slightly smaller than one crystal grain, the grain filter 13 can be formed above the opening (opening). Will reach only one crystal grain. As a result, in the substantially completely melted portion of the silicon film 14, crystal growth proceeds with one crystal grain reaching the upper portion of the grain filter 13 as a nucleus.
[0040]
FIG. 4 is a view for explaining the shape of the grain filter 13 suitable for performing the melt crystallization as described above. The grain filter 13 is preferably formed so that the ratio h / r of the depth h to the diameter r is greater than 2.75. That is, when the angle seen from the central axis (the z-axis in the figure) of the grain filter 13 toward the side wall of the grain filter 13 is φ, when h / r> 2.75, the angle φ is 20 Less than °. Within the grain filter 13, the crystal orientation of the silicon crystal grains is such that the (111) plane is directed in the z-axis direction. The (111) plane and the (331) plane have an angle of about 22 °. Therefore, by forming the grain filter 13 so that φ <20 ° with h / r> 2.75, the (331) plane having an angle of about 22 ° with the (111) plane is the grain filter. It grows toward 13 side walls. As a result, the (111) plane of the silicon crystal grains above the grain filter 13 appears preferentially, and the plane orientation is adjusted based on the (111) plane when the silicon film is crystallized. Can do.
[0041]
Further, when the grain filter 13 is formed with h / r> 5, the above-mentioned angle φ is smaller than 11 °, and the deviation of the plane orientation of the silicon crystal grains formed with the grain filter 13 as a substantially center is reduced. Further suppression is possible. Specifically, according to the inventors of the present application, it was confirmed that the deviation of the plane orientation between the plurality of silicon crystal grains formed based on the plurality of grain filters 13 on average was 10 ° or less. ing.
[0042]
Further, when the grain filter 13 is formed with h / r> 11, the above-mentioned angle φ is smaller than 5 °, and the deviation of the plane orientation of the silicon crystal grains formed with the grain filter 13 substantially at the center is further increased. Further suppression is possible. Specifically, according to the inventors of the present application, it has been confirmed that the deviation of the plane orientation between the plurality of silicon crystal grains formed based on the plurality of grain filters 13 is 5 ° or less on average. ing. Based on such examination results, in this embodiment, the depth h of the grain filter 13 is set to 825 nm, which is 11 times the diameter r (= 75 nm).
[0043]
(Element formation process)
By performing melt crystallization of the silicon film 14 as described above, the silicon film 18, which is a crystalline semiconductor film having a substantially single crystal state and a controlled plane orientation, with the grain filter 13 as a center. Can be formed. By using the silicon film 18 thus obtained, a high-performance semiconductor element (for example, a thin film transistor or a thin film diode) can be formed.
[0044]
Next, taking a thin film transistor as an example, a process for forming a semiconductor element using the crystalline semiconductor film (silicon film 18) according to the present invention will be described. By using the crystalline semiconductor film according to the present invention for an active region of a thin film transistor, a high-performance thin film transistor with low off-state current and high mobility can be formed.
[0045]
FIG. 5 is a diagram illustrating a thin film transistor forming process. First, as shown in FIG. 5A, the silicon film 18 is patterned, and a portion unnecessary for forming a thin film transistor is removed and shaped.
[0046]
Next, as shown in FIG. 5B, a silicon oxide film 20 is formed on the upper surfaces of the silicon oxide film 12 and the silicon film 18 by a film forming method such as an electron cyclotron resonance PECVD method (ECR-PECVD method) or a PECVD method. To do. This silicon oxide film 20 functions as a gate insulating film of the thin film transistor.
[0047]
Next, as shown in FIG. 5C, a gate electrode 22 and a gate wiring film (not shown) are formed by patterning after forming a conductive thin film such as tantalum or aluminum by a film forming method such as sputtering. Form. Then, a source region 24, a drain region 25, and an active region 26 are formed in the silicon film 18 by performing so-called self-aligned ion implantation by implanting an impurity element serving as a donor or acceptor using the gate electrode 22 as a mask. For example, in this embodiment, phosphorus (P) is implanted as the impurity element, and then XeCl excimer laser is applied at 400 mJ / cm. ² An N-type thin film transistor is formed by adjusting the energy density to a certain level and irradiating to activate the impurity element. Note that the impurity element may be activated by performing heat treatment at a temperature of about 250 ° C. to 400 ° C. instead of laser irradiation.
[0048]
Next, as shown in FIG. 5D, a silicon oxide film 28 having a thickness of about 500 nm is formed on the upper surfaces of the silicon oxide film 20 and the gate electrode 22 by a film forming method such as a PECVD method. Next, contact holes that penetrate each of the silicon oxide films 20 and 28 to reach the source region 24 and the drain region 25 are formed, and aluminum, tungsten, or the like is formed in these contact holes by a film forming method such as sputtering. The source electrode 30 and the drain electrode 32 are formed by embedding and patterning the conductor. As a result, as shown in FIG. 5D, a nickel layer 16 made of a metal-containing material and serving as a crystallization promoting material for promoting crystallization of the semiconductor film is disposed at the bottom of the grain filter 13, and the grain filter A thin film transistor T in which an active region 26 is formed using a silicon film 18 formed by melt crystallization from 13 is obtained.
[0049]
As described above, in the manufacturing method of the present embodiment, the grain filter 13 serving as a starting point when the amorphous (or polycrystalline) silicon film 14 is melt-crystallized is made of a metal-containing substance such as nickel. A crystallization promoting material and a semiconductor film compound are formed. As a result, when the silicon film 14 is melt-crystallized by heat treatment, a substantially single-crystal silicon film 18 (crystallinity) in which the crystal grains are large and the plane orientation is controlled in a range substantially centered on the grain filter 13. A semiconductor film) can be formed. Since the thin film transistor T is formed using a high-quality silicon film 18 having large crystal grains and controlled plane orientation, it is possible to improve the performance of the thin film transistor.
[0050]
Next, application examples of the thin film transistor manufactured by the manufacturing method of the present invention will be described. The thin film transistor obtained by the manufacturing method of the present invention can be used as a driving element of a liquid crystal display device or a driving element of an EL display device.
[0051]
FIG. 6 is a diagram illustrating a connection state of the display device 100 which is an example of the electro-optical device according to the present embodiment. As shown in FIG. 6, the display device 100 is configured by arranging a pixel region 112 in a display region 111. The pixel region 112 uses a thin film transistor that drives an organic EL light emitting element. A thin film transistor manufactured by the manufacturing method of the above-described embodiment is used. A light emission control line (Vgp) and a write control line are supplied from the driver area 115 to each pixel area. A current line (Idata) and a power supply line (Vdd) are supplied from the driver area 116 to each pixel area. By controlling the writing control line and the constant current line Idata, current programming is performed for each pixel region, and light emission is controlled by controlling the light emission control line Vgp. Note that the thin film transistor according to the present invention can also be used for the driver regions 115 and 116.
[0052]
FIG. 7 is a diagram illustrating an example of an electronic apparatus to which the display device 100 can be applied. As shown in the figure, the display device 100 according to the present invention can be applied to various electronic devices. FIG. 7A shows an application example to a mobile phone, and the mobile phone 230 includes an antenna unit 231, an audio output unit 232, an audio input unit 233, an operation unit 234, and the display device 100 of the present invention. Thus, the display device of the present invention can be used as a display unit. FIG. 7B shows an application example to a video camera. The video camera 240 includes an image receiving unit 241, an operation unit 242, an audio input unit 243, and the display device 100 of the present invention. Thus, the display device of the present invention can be used as a finder or a display unit. FIG. 7C shows an application example to a portable personal computer (so-called PDA). The computer 250 includes a camera unit 251, an operation unit 252, and the display device 100 of the present invention. Thus, the display device of the present invention can be used as a display unit.
[0053]
FIG. 7D shows an application example to a head mounted display. The head mounted display 260 includes a band 261, an optical system storage unit 262, and the display device 100 of the present invention. Thus, the display panel of the present invention can be used as an image display source. FIG. 7E shows an application example to a rear projector. The projector 270 includes a housing 271, a light source 272, a synthesis optical system 273, mirrors 274 and 275, a screen 276, and the display device 100 of the present invention. ing. Thus, the display device of the present invention can be used as an image display source. FIG. 7F shows an application example to a front projector. The projector 280 includes an optical system 281 and the display device 100 of the present invention in a housing 282, and can display an image on a screen 283. Thus, the display device of the present invention can be used as an image display source.
[0054]
The display device 100 according to the present invention is not limited to the above-described example, and can be applied to any electronic apparatus to which a display device such as an organic EL display device or a liquid crystal display device can be applied. For example, in addition to these, it can also be used for a fax machine with a display function, a finder for a digital camera, a portable TV, an electronic notebook, an electric bulletin board, a display for advertisements, and the like.
[0055]
In addition, this invention is not limited to the content of embodiment mentioned above, A various deformation | transformation implementation is possible within the range of the summary of this invention.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram illustrating a method for manufacturing a semiconductor device.
FIG. 2 is an explanatory diagram illustrating a method for manufacturing a semiconductor device.
FIG. 3 is a diagram showing a relationship between a processing temperature and a processing time during heat treatment.
FIG. 4 is a diagram for explaining the shape of a grain filter.
FIGS. 5A and 5B are diagrams illustrating a process for forming a thin film transistor. FIGS.
FIG. 6 is a diagram illustrating a connection state of a display device which is an example of an electro-optical device.
FIG. 7 illustrates an example of an electronic device to which a display device can be applied.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Substrate, 12, 20, 28 ... Silicon oxide film 13 ... Grain filter, 14 ... Amorphous (or polycrystalline) silicon film, 16 ... Nickel layer, 18 ... Crystalline silicon film, 100 ... Display Device, T ... Thin film transistor

Claims (15)

A method of manufacturing a semiconductor device in which a semiconductor element is formed on an insulating substrate,
Forming a hole on the insulating substrate; and
A semiconductor film forming step of forming a semiconductor film by forming a semiconductor material on the insulating substrate and in the hole;
From the semiconductor film, a crystallization promoting material driving step of driving a crystallization promoting material made of a metal-containing substance into the range from the opening to the bottom of the hole, which promotes crystallization of the semiconductor film;
A compound forming step of applying a first heat treatment to the semiconductor film to form a compound of the semiconductor film and the crystallization promoting material in the hole;
By applying a second heat treatment to the semiconductor film, the semiconductor film is melt-crystallized so that a non-molten portion remains in the holes and the other portions are substantially completely melted, and the holes A melt crystallization step of forming a crystalline semiconductor film starting from one crystal grain reaching the top of
A method of manufacturing a semiconductor device including:   The method for manufacturing a semiconductor device according to claim 1, further comprising an element forming step of forming a semiconductor element using the crystalline semiconductor film.   3. The semiconductor device according to claim 1, wherein the hole formed on the insulating substrate is formed such that a ratio h / r of a hole depth h to a hole diameter r is larger than 2.75. Manufacturing method.   The semiconductor device according to claim 1, wherein the hole formed on the insulating substrate is formed such that a ratio h / r of a hole depth h to a hole diameter r is larger than 5. 4. Method.   3. The semiconductor device manufacture according to claim 1, wherein the hole formed on the insulating substrate is formed such that a ratio h / r of a hole depth h to a hole diameter r is larger than 11. 4. Method.   The method for manufacturing a semiconductor device according to claim 1, wherein a diameter of the hole formed on the insulating substrate is 45 nm or more and 190 nm or less.   The method for manufacturing a semiconductor device according to claim 1, wherein a film thickness of the semiconductor film formed in the semiconductor film forming step is 30 nm or more and 100 nm or less.   The method for manufacturing a semiconductor device according to claim 1, wherein the semiconductor film formed in the semiconductor film forming step contains silicon as a main constituent element.   9. The method of manufacturing a semiconductor device according to claim 1, wherein the crystallization promoting material is implanted so that the crystallization promoting material is concentrated near a bottom portion of the hole.   The method for manufacturing a semiconductor device according to claim 1, wherein the crystallization promoting material is a substance containing any of nickel, iron, cobalt, platinum, and palladium.   The method for manufacturing a semiconductor device according to claim 1, wherein the crystallization promoting material is a silicon compound (silicide). The crystallization promoting material is implanted in the crystallization promoting material implantation step when the semiconductor film has a thickness of 50 nm, the hole depth is 825 nm, and the crystallization promoting material is a nickel-containing substance. the 1 MeV, are performed and the dose amount of 10 ¹⁶ ~10 ¹⁸ cm ^-2, the method of manufacturing a semiconductor device according to any one of claims 1 to 5.   The method for manufacturing a semiconductor device according to claim 1, wherein the first heat treatment is performed at 300 ° C. or more and 550 ° C. or less. The treatment time t (second) of the first heat treatment is as follows: treatment temperature T (° C.), Boltzmann constant k _B = 8.617 × 10 ⁻⁵ eV · K ⁻¹ , ε = 0.833 eV, t ₀ = 1. When 59 × 10 ^-3 (seconds),
t ≧ t ₀ · exp {ε / k _B (T + 273.16)},
The method for manufacturing a semiconductor device according to claim 1, wherein the method is set so as to satisfy the relationship.   The method for manufacturing a semiconductor device according to claim 1, wherein the second heat treatment is performed by laser irradiation.

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