JP2797104B2 - Method for manufacturing semiconductor crystal layer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a semiconductor crystal layer. More specifically, the present invention relates to a method called SOI (Semiconductor on Insulator) technology, which is performed by solid phase epitaxial growth on an insulator layer. The present invention relates to a method for manufacturing a semiconductor crystal layer for forming a single crystal semiconductor layer. The above SOI is now acronym for Silicon on Insulator when used in a narrow sense.

[Prior art] Many studies are currently being conducted with the aim of improving the performance of semiconductor integrated circuits. However, in terms of materials, compound semiconductors and semiconductor layers on insulator films, that is, SOI (Silicon on Insulator)
Are being studied.

In particular, the latter (SOI) realizes a highly integrated and high-speed integrated circuit because the integrated circuit manufacturing process in the current silicon technology can be utilized almost as it is, the element isolation is easy, and the parasitic capacitance is small. be able to. SOI is an indispensable structure for the production of three-dimensional integrated circuits, and is considered to be a promising candidate for next-generation integrated circuits. In addition, SOI by solid-phase epitaxial growth does not require silicon to be heated to its melting point or higher, so the manufacturing temperature is low and energy saving. This is indispensable for realizing the drive circuit.

In addition to the above, SOI is expected to be applied to a high breakdown voltage device and a radiation-resistant device by utilizing the above-described ease of element isolation. In addition, if the SOI semiconductor layer is achieved in a large area, it is a material suitable for forming an active matrix for a display device such as a liquid crystal television, a facsimile licensing signal processing device, and the like. Therefore,
In particular, the results of research on SOI by solid phase epitaxial growth have been strongly expected in recent years.

Solid phase epitaxial growth (hereinafter abbreviated as SPE growth, Solid
Phase Epitaxial Grow is an abbreviation for abbreviations), for example, amorphous silicon (hereinafter a-type) on an insulator layer (SiO ₂ film).
When single crystallizing Si, the melting point of Si (1415
Crystal growth can be performed at a temperature (800 ° C. or less) much lower than (° C.), and there is an advantage that a large area single crystal silicon (hereinafter abbreviated as c-Si) film can be grown using this. is there. However, on the other hand, the growth rate is lower than that of the well-known seeding melting and recrystallization method using laser beam or electron beam irradiation, and furthermore, the single crystal (c−
The disadvantage that Si) quality is somewhat inferior is pointed out, and improvement of this defect is a decisive factor in development.

When trying to obtain large-area c-Si by the SPE growth method, the hindrance is polycrystallization. That is, a thin film of a-Si is formed on an insulator layer such as a silicon oxide film (SiO ₂ ), and when this a-Si is heated and annealed, the a-Si
C-Si phase gradually from the seeding part of the single crystal adjacent to
While SPE grows, fine crystal nuclei are generated in a-Si, and these crystal nuclei grow. And since the crystal orientation of this crystal nucleus is random, it becomes polycrystalline,
Large lateral SPE due to this random nucleation
The growth distance could not be obtained.

That is, in the conventional SPE growth method using a simple furnace annealing method for performing uniform heating, the lateral SPE growth distance has no example exceeding 100 μm, which is a conclusion consistent with the results of preliminary experiments by the present inventors. It is not possible to say that it is possible to increase the area even with compliments. SPE for forming high quality and dramatic large area c-Si thin film on insulator layer
That is why technical development of the growth method is desired.

Therefore, the present inventors have continued basic research on the crystallization process of a-Si in order to obtain a high-quality, large-area c-Si thin film by SOI technology. As a result, the random nucleation as described above does not occur immediately when the a-Si is heated, but occurs in a time period such as an induction time (crystallization time) until crystallization occurs around the nucleus. We have learned that there is a delay. Then, from this knowledge, we focused on the induction time and gained insight,
We have developed a method for SPE growth of large-area single-crystal semiconductor layers by the annealing method that suppresses polycrystallization due to random nucleus growth as described above.

Based on the results of this research, a part of the present applicant has previously filed a patent application for an invention relating to "a method for manufacturing a semiconductor crystal layer" as Japanese Patent Application No. 63-66848 (hereinafter referred to as the prior invention). . The present invention is basically based on the present invention. An amorphous semiconductor layer is formed on an insulator layer, and the amorphous semiconductor layer is annealed under a temperature condition having a steep rising temperature gradient. It is characterized in that a single-crystal semiconductor layer is grown on the insulator layer by SPE by relatively moving the annealing region.

Assuming that the above-mentioned steep temperature gradient is κ, κ sets annealing conditions to satisfy the following equation and performs annealing.

Here, T _i is the initial temperature, T _ep is the solid phase epitaxial set temperature, E _a is the activation energy of the induction time, k is the Boltzmann constant, T is the temperature, V is the moving speed of the amorphous semiconductor layer, τ _o Is a constant and is an induction time until the generation of a crystal nucleus at an infinite temperature.

Further, a metal layer for seeding is provided on the insulator layer or a part of the amorphous semiconductor layer, and a short crystal is formed from a eutectic region formed between the adjacent metal layer and the amorphous semiconductor layer. The semiconductor layer is grown by SPE.

Here, a more detailed description will be given below. This annealing method is called a lateral annealing method, and a-Si is monocrystallized in the lateral direction by utilizing the balance between the above-mentioned induction time (used as t _d in the above invention) and the crystal growth rate. Improved SPE growth method, LSP.
E growth method.

FIGS. 7A and 7B are schematic explanatory views showing the principle of lateral annealing. In FIG. 7, for ease of explanation, a temperature distribution curve corresponding to the lateral distance of the SOI material 13 is shown in the upper part of FIG. ).

In FIG. 7 (b), the SOI material 13 is formed by forming an a-Si film 2 on a quartz glass substrate 1 and depositing Au (gold) on the right end of the quartz glass substrate 1 to form an Au-Si film. The one formed by forming the crystal layer 4a is used. If SOI material 13 is installed in the cooling stage 6 made of copper blocks which are used as cooling stage also serves as the support, and the cooling stage 6 is the initial temperature of the temperature T _i.

In this case, the SOI material 13 near the end of the cooling stage 6 is used.
Heating the at the position of the temperature of the run to T _i of the distance L to keep the set temperature T _ep of SPE growth (Figure 7 (b) refer), linearized with some way (or point-like) . Actually, the heating light beam 24 collected from a linear lamp (not shown),
Irradiating the heated line part 37 is heated to a temperature T _2. In this state, SO
The material 13 for I can be considered to have a somewhat steep temperature gradient as shown by the curve shown in FIG. 7 (a).

In such a system, the crystal growth end 38 reaches the set temperature T _ep
In order to maintain the state after that, material for SOI 1
3 can be moved at the crystal growth rate v _spe = V at the set temperature T _ep . That is, the SPE speed at the set temperature T _ep is v
_{In the case of spe} , when the SOI material 13 is moved rightward at the speed V, a point of the SOI material 13 is changed from the initial temperature _Ti to the set temperature T.
The time to reach _ep is t = L / V. If the a-Si film 2 does not generate random nucleation within this time t, the a-Si film 2 is grown by SPE without being hindered by polycrystallization.
Can be single-crystallized to form the c-Si film 3. That is, it is necessary that the effective induction time when the SOI material 13 passes through the temperature gradient is smaller than t = L / V, and this condition is expressed by Expression (1).
The above is the principle of lateral annealing.

In other words, this principle is based on simple annealing of a-Si by uniform heating such as electric furnace annealing, which results in microcrystallization due to random nucleation.Therefore, a temperature gradient is applied to the sample to prevent nucleation and SPE growth. That's what I mean.

In the above invention, a lateral annealing furnace was actually developed based on the principle of the lateral annealing, and a-Si on the insulator layer was transferred in the lateral direction SP using the lateral annealing apparatus.
A relatively large area c-Si layer can be formed by the E growth method.

[Problems to be Solved by the Invention] In the above-described method of manufacturing a semiconductor crystal layer by SPE growth shown in the above invention, the semiconductor crystal layer formed on the insulator layer has a lateral SPE. Growth distance is about 2mm
The size is 44 to 44 by the conventional uniform annealing method.
The value is about two orders of magnitude larger than the value of 100 μm, indicating a dramatic technical improvement. However, the value of about 2 mm is far from the practical use of a SOI structure formed by SPE growth in a device, and a further increase in area is required. However, as shown in the earlier application, it was expected that improvements could be made to the order of cm by improving the temperature control of the lateral annealing furnace, etc. About 4mm
Only a modest degree of crystalline layer (this layer is observed as a yellow transparent area) is obtained. Further, even when a crystal layer of this size is obtained, there is a problem that its reproducibility is poor. Therefore, in the future, solving the problem of reproducibility in particular will be an issue leading to SPE growth of c-Si having a single crystal or large grain boundary crystal film.

The present invention has been made in order to solve the above-mentioned problems, and is a semiconductor which can improve the manufacturing method according to the previous invention and grow a large-area single crystal semiconductor layer with good reproducibility and in a stable state by SPE. It is an object of the present invention to provide a method for manufacturing a crystal layer.

[Means for Solving the Problems] According to a method for manufacturing a semiconductor crystal layer according to the present invention, an amorphous semiconductor layer is formed on an insulator layer, and a part of the amorphous semiconductor layer for seeding is formed. A metal layer is provided to form a eutectic region with this metal layer, or a contact portion with a single crystal semiconductor is provided for seeding, and a non-transmissive heat absorbing film formed of an opaque body is formed thereon. By annealing the crystalline semiconductor layer under a temperature condition having a steep rising temperature gradient and moving the annealing region relatively unidirectionally at a predetermined speed, the semiconductor crystal in the eutectic region or the contact portion is seeded. Is to grow a single crystal semiconductor layer in the lateral direction by SPE. In this case, the above-mentioned steep temperature gradient causes a linear or dotted narrow heating means formed in a direction perpendicular to the SPE growth direction (horizontal direction) to anneal with an amorphous semiconductor cooling region. It is formed in the region between.

[Operation] In the present invention, the amorphous semiconductor layer is moved and annealed under the temperature condition having a steep rising temperature gradient, and the single-crystal semiconductor layer is grown by SPE. It can be set so that random nucleation does not occur until the point reaches the SPE growth set point.
In other words, by moving and annealing the amorphous semiconductor layer under a temperature condition having a steep rising temperature gradient, the initial temperature of the low temperature can be reduced within a time shorter than the effective induction time for random nucleation. The temperature can be raised at a stretch to the epitaxial setting temperature, and therefore, before random nucleation occurs in the amorphous semiconductor layer, the crystal plane with the highest crystallization speed is non-crystallized by SPE growth from the already crystallized region. Since it penetrates into the crystalline semiconductor layer, the formation of the polycrystalline layer can be suppressed and the single crystal semiconductor layer can be grown.

Here, the steep rising temperature gradient κ is expressed by the following equation when the temperature change is linearly approximated. (Where L is the distance from end to end of the region changing from the initial temperature T _i to the solid-phase epitaxial set temperature T _ep ). Speed V
Is set so as to satisfy the above equation (1), the solid phase epitaxial set temperature is reached within a time shorter than the effective induction time of the amorphous semiconductor layer passing through the temperature gradient. Can be done. Therefore, the lower limit of the required rising temperature gradient can be quantified by equation (1).

The above is the basis of the present invention and is as described in the previous invention. In addition to this, in the present invention, an amorphous semiconductor film to be monocrystallized on an insulator film coated with a heat absorbing film made of an opaque object is used as a material for SOI. This is useful for improving the heating efficiency in annealing. That is, when there is no endothermic film coating, once the amorphous semiconductor film is crystallized, this portion becomes a transparent film as described above, and the heating light beam is almost transmitted. For this reason, it is considered that the film is difficult to be heated, and does not actually reach the initial temperature, causing an inconvenience that unnecessary heating is performed in order to obtain the set temperature T _ep . Further, in such a state, it is considered that the SPE growth process becomes non-equilibrium in heat dissipation and heat absorption even with the elapse of time, so that stable SPE growth is hardly performed. Therefore, the presence of this endothermic film not only solves the above-mentioned problems and improves the heating efficiency, but also improves the SPE.
It contributes to stabilization of the temperature distribution during growth.
This is an important factor in manufacturing conditions.

In addition, by providing a contact portion with a single-crystal semiconductor of the same material and by forming a seeding metal layer on the insulator layer, a eutectic region serving as a seeding portion is formed to achieve stable SPE growth. Can be realized.

[Example] Hereinafter, an example of the present invention will be sequentially described with reference to the accompanying drawings in terms of the production of SOI materials, the configuration of a lateral annealing furnace, the manufacturing procedure, and the results.

1) Production of SOI Material FIG. 1 is a schematic sectional view showing one embodiment of an SOI material for forming a semiconductor crystal layer according to the present invention. In the figure, reference numeral 13 denotes an SOI material. First, a-S is formed on the surface of a quartz glass substrate 1 (insulator layer) by plasma CVD.
An i film 2 (amorphous semiconductor layer) is formed. That is, a-Si
The film 2 is formed as a material layer that is crystallized by SPE growth to form a c-Si film.

Further, a thin gold (Au) film 4 (metal layer) for seeding at one end of the a-Si layer 2 is provided by vapor deposition. That is, the metal 4 is formed adjacent to the a-Si film 2, and the formation of the gold film 4 enables the formation of the metal 4 at a low temperature of 377 ° C.
A Si-Au eutectic region can be formed in a region adjacent to -Si, and the existence of a Si seed crystal can be ensured. The metal material of the metal 4 is gold (Au).
The present invention is not limited to this, and for example, aluminum (Al) may be used.

Then, soot (opaque soot) was applied almost uniformly on the a-Si film 2 on which the metal 4 was provided to form a heat absorbing film 30, thereby producing a material 13 for SOI. In this embodiment, the heat absorbing film 30 is used.
Although soot was used as a material for the material, this material is an opaque material that absorbs light or heat rays, and may be any heat absorbing material that can be easily separated and removed from the crystalline semiconductor layer generated after the SPE process. It is not limited to soot.

2) Structure of lateral annealing furnace Fig. 2 shows lateral solid phase epitaxial growth (hereinafter referred to as LSPE).
FIG. 5 is a schematic cross-sectional view of a principal part of a lateral annealing furnace for performing growth). This lateral annealing furnace 5 has a SO
It comprises a cooling stage 6 for the I material 13, a support stage 7 for the SOI material 13, a fine movement feeder 8 for the SOI material 13, a spot-shaped local heating device 9, a linear local heating device 10, and the like.
FIG. 3 is a schematic illustration of the essential parts of the lateral annealing furnace 5, the spot-shaped local heating device 9 and the linear local heating device 10 shown in FIG.

The cooling stage 6 and the support stage 7 support the SOI material 13 horizontally and move it smoothly.
In each case, a plate made of a material having high thermal conductivity, for example, a copper plate or the like is used, and the upper surface thereof is finished smoothly. Further, the cooling stage 6 and the supporting stage 7 are horizontally supported by columns 11 and 12, respectively, and the front ends thereof are opposed to each other such that the upper surfaces are flush with each other at the same height. A small gap 14 is formed between the stage 6 and the support stage 7 over almost the entire width. Further, the cooling stage 6
Is provided with a structure (not shown) for circulating water inside or below, and is cooled by a water cooling method.

The fine movement feeder 8 includes a push rod 15 for pushing the rear end of the SOI material 13 to move the SOI material 13 and a feeder body 16 for moving the push rod 15 horizontally and very precisely at a constant speed. And is provided on the cooling stage 6 side. The SOI material 13 placed on the cooling stage 6 and the supporting stage 7 is moved at a predetermined speed V from the cooling stage 6 to the supporting stage 7 by the fine movement feeding device 8.

The spot-shaped local heating device 9 is disposed above the cooling stage 6 and the support stage 7, and includes a laser oscillator 17 and an optical system 18 for condensing light, as shown in FIG. Then, as shown in FIGS. 2 and 3, the laser beam 19 emitted from the laser oscillator 17 is narrowed down by the optical system 18 and mounted on the cooling stage 6 and the support stage 7 at the position of the small gap 14. It is adjusted so as to focus on a point at approximately the center of the upper surface of the placed SOI material 13. The laser oscillator 17 used here is a semiconductor laser having a wavelength of 800 nm and an output of 100 mW. In the embodiment, the spot-shaped local heating device 9 is used.
Although a semiconductor laser is used as the above, other lasers may be used, or an ion beam, an electron beam, or a laser whose light from a lamp is narrowed down by an optical system may be used. In this case, the position of the laser beam 19 is fixed in view of the power, and the laser beam 19 is not scanned in the width direction of the SOI material 13. However, when a high-power laser is used, it may be scanned in the width direction. Can be

The linear local heating apparatus 10 has a linear heat source 21 disposed in an elliptical reflection furnace 20 having an elliptical reflection surface 22. The elliptical reflecting furnace 20 is obtained by mirror-finishing an elliptical reflecting surface 22 by gold plating, and the elliptical reflecting surface 22 is formed so as to have an elliptical cross section (thus, a three-dimensionally elliptical cylindrical body). The linear heat source 21 is arranged at a focal point below the elliptical reflection surface 22. The elliptical reflecting surface 22 is opened without an upper portion, and the elliptical reflecting furnace 20 is installed so that the cooling stage 6 and the supporting stage 7 are located in the upper opening. Further, a small gap 14 between the cooling stage 6 and the supporting stage 7 is located at the center of the elliptical reflecting furnace 20, and the focal point above the elliptical reflecting surface 22 is placed on the cooling stage 6 and the supporting stage 7. Was
The SOI material 13 is adjusted so as to have the same height as the a-Si film 2 (however, the SOI is so set that the light from the linear heat source 21 passes through the quartz glass substrate 1 and hits the a-Si film 2). Materials 1
When 3 is installed, the refraction of light by the quartz glass substrate 1 is taken into consideration. ). Therefore, the heat rays emitted from the linear heat source 21
24 is reflected by the elliptical reflection surface 22 and heat is collected at the surface position of the a-Si film 2 of the sample 13. As the linear heat source 21, a halogen lamp, an infrared lamp, a Kanthal ribbon heater, or the like can be used. In particular, a halogen lamp is preferable. As the linear local heating device 10, the cooling stage 6 and the Although it is possible to simply provide a Kanthal ribbon heater or the like in the vicinity of the support stage 7, the reproducibility of single crystal growth can be improved by using the elliptical reflection furnace 20 as described above.

3) Manufacturing procedure and its results FIG. 4 shows that the a-Si film 2 on the SOI material 13 shown in the embodiment of FIG. 1 is crystallized by LSPE growth by the lateral annealing furnace of FIG. FIG. 3 is a schematic view showing a state in which is formed. Hereinafter, a method for forming a semiconductor crystal layer according to the present invention will be described with reference to FIGS.

First, the SOI material 13 is placed on the cooling stage 6 and the supporting stage 7 in the air atmosphere, and the metal 4 and the a-
The region where the Si film 2 overlaps is heated. Thus, a eutectic region 23 of gold and silicon is formed, and this eutectic region 23 becomes a seed crystal for single crystal growth. Next, the SOI material 13 is pushed by the fine movement feeder 8 and moved horizontally at a constant speed V while the surface of the SOI material 13 is heated by the spot-shaped local heating device 9 and the linear local heating device 10. In this manner, the annealing region of the SOI material 13 moves along with the movement of the SOI material 13, and the c-Si
The film 3 (single crystal semiconductor layer) gradually grows from the eutectic region 23 by solid phase epitaxial growth.

Looking at this by paying attention to a certain cross section of the SOI material 13, first, the SOI material 13 is cooled to the initial temperature _Ti on the cooling stage 6, and the small gap 14 extends beyond the end of the cooling stage 6.
When it comes out above, it is rapidly heated by the linear local heating device 10 from below. Therefore, the SOI material 13 is rapidly heated to the solid-phase epitaxial set temperature _Tep under a steep rising temperature gradient. Furthermore, since the central portion is heated by the spot-shaped local heating device 9 from above,
Annealed under a steeper rising temperature gradient.

FIG. 5 is a diagram showing a temperature change along the length direction of the SOI material 13. In the figure, the horizontal axis is the horizontal distance measured along the SOI material 13, the vertical axis is the temperature, and “a” on the horizontal axis corresponds to the end of the cooling stage 6. In this diagram,
The solid line B indicates the state of being cooled by the cooling stage 6, the broken line D indicates the state of heating by the linear local heating device 10, and the two-dot chain line E indicates the state of heating by the spot-like local heating device 9. The solid line F indicates the slow cooling state on the sample support stage 7 side. Although the heating curve by the linear local heating device 10 has a steep rising characteristic, it rises relatively broadly compared to the heating area by the spot local heating device 9.
For this reason, when heating by the spot-shaped local heating device 9 is superimposed on heating by the linear local heating device 10, a steeper rising temperature gradient can be obtained as indicated by a solid line C in FIG. In this manner, the sample 13 is moved under the temperature condition of the steep rising temperature gradient to anneal the amorphous silicon film 2 on the surface, thereby quickly increasing the temperature to SP.
It becomes possible to raise the temperature to the E growth set temperature T _ep . Then, random nucleus for Raising the temperature of the a-Si film 2 to SPE growth set temperature T _ep in less time than induction time for nucleation, has not passed yet effective induction time The a-Si film 2 in which no generation has occurred and the SPE growth set temperature T _ep has been reached is formed in the eutectic region 23.
The c-Si film 3 is generated by SPE growth from. As a result, a large-area c-Si film 3 containing no polycrystalline silicon
Is obtained.

Fig. 6 shows the material for SOI obtained by growing SPE in this way.
13 is a schematic plan view showing 13. FIG. In the figure, the right end is the deposited gold layer 4, which is first heated and
A eutectic is formed at 377 ° C. The left end is the unannealed portion of the a-Si film 2, and the heat absorbing film 30 made of a black medium formed thereon remains unchanged. The central portion is a single crystallized c-Si film 3, which is light yellow and transparent because it has a smaller visible light absorption coefficient than the amorphous phase. The length s of this part is LS
It is the PE growth distance. According to the results of the experiment, s was about 10 mm or more.

The value of the LSPE growth distance s of 10 mm shows an improvement of about 4 times or more compared to the value of 2 mm of the result of the previous invention. This is achieved by providing on the a-Si film 2. That is, when the c-Si film 3 is formed as described above, the c-Si portion becomes a pale yellow transparent film when the heat-absorbing layer 30 is not provided, as described in the description of the invention above. Heat rays 24 and laser light 19 are easily transmitted,
For this reason, heat absorption (annealing) with a temperature gradient due to local heating and cooling due to the decrease in heat absorption efficiency due to heat radiation from this part becomes non-equilibrium because the actual SPE set temperature is lowered. Conceivable. In the manufacturing method according to the present invention, the heat absorbing efficiency is increased by forming the heat absorbing layer 30 on the a-Si film 2, the equilibrium state of the heat absorbing and radiating is constantly maintained, and the reproducibility of the SPE growth is improved. Therefore, the crystallized region can be grown largely in a stable state to form an SPE grown film. The heat absorbing layer 30
Since is a fine powder of carbon, it has an advantage that it is combined with oxygen in the atmosphere at the time of single crystallization by SPE growth, becomes CO ₂ , is very conveniently vaporized, and is removed from the c-Si film 3. The material of the heat absorbing layer 30 is not limited to carbon powder such as soot, and it goes without saying that any substance having the same effect may be used.

In the LSPE process shown in this embodiment, the a-Si film 2 not irradiated with the spot-shaped local heating device 9 was used.
Are also annealed under the temperature condition having a steep rising temperature gradient as shown by the broken line d in FIG. 5, but on both sides, the SPE is dragged by the central part where the LSPE speed is large and the SPE is Progressing. That is, since the central portion is heated by the spot-shaped local heating device 9 and has a higher temperature than both sides, it has a large LSPE growth rate, and this central portion becomes a seed crystal as shown in FIG. As shown in FIG. 6, the left edge of the c-Si film 3 looks like a V-shape as shown in FIG. Therefore, if the moving speed V of the SOI material 13 is changed, it is presumed that the angle of the V-shape also changes.

The a-Si film 2 to be formed on the SOI material 13 and to be single-crystallized by SPE growth may be formed by any method.
(Hydrogen) a-Si of 1% or less has obtained relatively good results.

Furthermore, for the actual annealing conditions in the above production process, the annealing temperature is less than the melting point of silicon, but T _ep temperature of 700 ° C. to 900 ° C. is considered appropriate, annealed at about 780 ° C. In the above example It is estimated that this was done. As the SPE growth rate V (= v _SPE ), a value of about 1000 μm / h has been achieved.

In the above embodiment, the case where the eutectic region with the metal layer formed in a part of the amorphous semiconductor layer is used as a seed crystal for seeding is described. With the contact part, and use this contact part as a seed
Similar effects can be obtained by forming the SOI material and applying the manufacturing method of the present invention.

[Effects of the Invention] As described above, according to the present invention, a contact portion with a metal layer for seeding or a single crystal semiconductor is provided on a part of an insulator layer, and SPE is grown on the whole. SO having a crystalline semiconductor layer formed thereon and an endothermic layer provided on this amorphous semiconductor layer
A material for I is manufactured, and the amorphous semiconductor layer of the material for SOI is annealed under a temperature condition having a steep temperature gradient, and the annealing region is moved at a predetermined speed to grow the lateral SPE. Since the semiconductor crystal layer is formed on the insulator layer, the heating efficiency is remarkably improved by increasing the endothermic effect at the time of annealing, and a large-area semiconductor crystal layer formed by SPE growth can be formed stably with good reproducibility.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view illustrating a method for forming an SOI material according to an embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view of a main part of a lateral annealing furnace (apparatus) used for performing LSPE growth. FIG. 3 is a schematic explanatory view of a main part of the lateral anneal furnace centering on a heated portion, FIG. 4 is a schematic view showing a state in which LSPE growth of a material for SOI is progressed by the lateral anneal furnace, and FIG. A diagram explaining the temperature change along the length direction of the SOI material sometimes, FIG. 6 is a schematic plan view showing the form of the SOI material obtained by LSPE growth, and FIG. 7 explains the principle of lateral annealing FIG. 7 (a) is a diagram showing a temperature distribution corresponding to a lateral distance of the a-Si layer during heating, and FIG. 7 (b) is a relationship between SOI material and heating means. FIG. In the figure, 1 is a quartz glass substrate, 2 is an a-Si film, 3 is a c-Si film, 4 is a metal, 4a is an Au-Si eutectic region, 5 is a lateral annealing furnace, 6 is a cooling stage, and 7 is a support. stage,
8 is a fine movement feeder, 9 is a spot-shaped local heating device, 10 is a linear local heating device, 11 and 12 are columns, 13 is a material for SOI, 14 is a small gap, 15 is a push rod, 16 is a feeder body, 17 is a laser oscillator, 18 is an optical system, 19 is a laser beam, 20 is an elliptical reflection furnace, 21 is a linear heat source, 22 is an elliptical reflection surface, 23 is a eutectic region of Au-Si, 24 is a hot wire, and 30 is endothermic It is a film (soot film).

────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Keiichi Nakagawa 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Nippon Kokan Co., Ltd. (56) References JP-A-61-44785 (JP, A) JP-A-61 JP-A-44786 (JP, A) JP-A-60-240118 (JP, A) JP-A-62-292427 (JP, A) JP-A-59-50515 (JP, A) JP-B-7-34431 (JP, B2) (58) Field surveyed (Int.Cl. ⁶ , DB name) H01L 21/20

Claims (2)

(57) [Claims] An amorphous semiconductor layer is formed on an insulator layer,
A metal layer for seeding is provided on a part of the amorphous semiconductor layer, a eutectic region is formed by the metal layer and the amorphous semiconductor layer, and the amorphous semiconductor layer has a sharp rising temperature. Annealing under a temperature condition having a gradient, and a method of manufacturing a semiconductor crystal layer in which a single crystal semiconductor layer is solid-phase epitaxially grown in a moving direction from the eutectic region by moving the annealing region at a relative moving speed, The moving speed V is the measurement temperature Te of the solid phase epitaxial growth.
A method for manufacturing a semiconductor crystal layer, wherein an opaque endothermic film having the same speed as the single crystal growth speed Vspe at p and absorbing light or heat rays is formed in advance on the amorphous semiconductor layer. 2. The method according to claim 1, wherein the opaque endothermic film is made of fine carbon powder.