JPS63285184A - Production of single crystal film - Google Patents

Abstract

PURPOSE:To enable the production of a single crystal film having little crystal defects at a high speed, by forming a polycrystalline or amorphous Si film on a single crystal growth seed or insulation film of the edge of a single crystal Si substrate or other regions and converting the Si film to single crystal with an energy beam. CONSTITUTION:A specimen is placed on a carbon heater 1 heated at a specific temperature by electric current. The specimen is composed of a single crystal Si substrate 2 coated its major part with an insulation film such as SiO2 film, Si3N4 film or their double-layer structure film and a part of the insulation film 3 is etched to open a window through which the substrate 2 is exposed at the edge part. The exposed part of the substrate is used as a growing seed part 4 for single crystal Si and the surface of the part is made to form nearly a plane with the surface of the insulation film 3. A polycrystalline Si film 5 is formed on these surfaces by CVD process, the part of the growing seed 4 connected with the substrate 2 contacting with the film 5 is linearly irradiated with energy beam 6 such as electron ray in the direction of X and the film is transferred in the direction Y under partial melting. The part of the polycrystalline Si converted to single crystal during the cooling process grows continuously in the direction Y to form a single crystal Si film having nearly flat surface over the whole surface.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a single crystal film, and more particularly to a method for manufacturing a single crystal Si film on an insulator, among methods for manufacturing a single crystal semiconductor film on an insulator.

The method for manufacturing a single crystal semiconductor film on an insulator is usually S.
OS C3iLicbn On 5apDhire)V
, Representative Sale;S.

There is a method of forming a Si semiconductor film on a single crystal sapphire substrate by an epitaxial method.

However, in the conventional technology, the grown single crystal semiconductor S
Because there is no crystal plane in which the interstitial constant of the two films perfectly matches the interstitial Z number of the grown Si single crystal film and the interstitial constant of the substrate sapphire single crystal, it is best to keep the lattice constant difference to a few percent at most. Another drawback is that the St single crystal film has many crystal defects.

Furthermore, the sapphire substrate is expensive, and although there is a strong demand for manufacturing high-speed semiconductor devices using such a single crystal semiconductor film on an insulator, practical implementation has been delayed.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate such drawbacks and to provide a semiconductor substrate for a high-speed semiconductor device, which is inexpensive and has a semiconductor single crystal film formed on an insulator with few crystal defects.

The basic configuration of the present invention for achieving the above object is that a single crystal and a growing seed made of a second solid crystal are provided on a part of the first solid surface, and the solid single crystal growing seed has at least forming a substrate on which a film made of the same material as the second solid material or a third solid material film in a polycrystalline or amorphous state is formed and is in contact with the surface of the first solid; While keeping the temperature slightly lower than the melting point of the material film, an energy beam such as an electron beam or a light beam is irradiated from at least the portion where the solid single crystal growth seed and the solid material film are in contact with each other, and the energy beam is moved and scanned while melting. - The solid material film on the first solid surface is solidified into a single crystal by a beam, and the solid material film is solidified into a single crystal on the substrate surface through a substantially continuous melting and cooling process. shall be.

The present invention will be described in detail below using examples.

FIG. 1 schematically shows an embodiment of the present invention, in which 1 is a carbon heater, and the heating temperature is 1200°C to 1300°C.
A sample is placed on the carbon heater, and most of the Si substrate 2 is made of Si.
, film, Si3N, film, or SiO□ and Si, N,
An insulating film 3 such as a 2N structure film is coated, a part of the insulating film 3 is opened by etching to expose the underlying Si substrate, and the exposed Si substrate part is used as a growth seed part 4 of single crystal Si.
A polycrystalline Si film 5 is formed on those surfaces by the CVD method, and an energy beam 6 such as an electron beam or a laser beam is applied to the growing seed 4 portion of the target crystalline Si film 5 substantially in the X direction. By irradiating the polycrystalline Si film 5 in a linear manner and moving it in the Y direction while partially melting it at about 1400°C, the portion 7 where the melted polycrystalline Si has become single crystal in the cooling process becomes Y The polycrystalline Si film 5 grows continuously in the direction, and the polycrystalline Si film 5 becomes a single crystal growth seed over the entire surface.

The form of the sample substrate is a single crystal that serves as a single crystal growth seed that is embedded on the surface of a glass or ceramic substrate 11 such as quartz, or embedded in the substrate 11. If 9N2 is attached to the substrate with a head cloth glass or the like, or if the polycrystalline S1 film 13 is formed by the CVD method, the CvD polycrystalline Si film 13 is directly attached to the substrate 1.
1 may be pasted onto it and a CVD5iOt film 14 may be coated thereon.

The single crystal grown seed on the insulator formed in this way becomes a single crystal film in which the crystallinity of the grown seed is maintained as it is,
It has the advantage that it has few crystal defects and does not need to be an expensive substrate such as sapphire, and can provide a substrate suitable for manufacturing high-speed semiconductor devices at a low cost.

[Brief explanation of drawings]

FIG. 1 schematically shows an embodiment of the present invention.
FIG. 2 shows a cross-sectional view of another example of the structure of the substrate sample. 1... Carbon heater 2... 51 board 3.
14... Insulating film 4, 12... Single crystal growth seed portion 5, 13... Polycrystalline Si film 6... Energy beam 7... Single crystal growth seed 11... Insulating substrate. Applicant: Seiko Epson Co., Ltd. Representative Patent Attorney Masayoshi Kamihi and one other person Figure 1 Figure 2 Procedural amendment (voluntary) May 20, 1988 2 Name of the invention Method for manufacturing single crystal film Representative Director Specification by Tsuneya Nakamura (full text amended) Description 1, Name of the invention Method for producing a single crystal film 2, Claims The energy beam is applied to the entire amorphous Sf, and 1. Shinki or amorphous Sf. A method for producing a single crystal film, characterized in that a method for manufacturing a single crystal film is performed. 3. Detailed Description of the Invention The present invention relates to a method for manufacturing a single crystal film, and particularly to a method for manufacturing a single crystal S1 film on an insulator among methods for manufacturing a single crystal semiconductor film on an insulator. Conventionally, the method of manufacturing a single crystal semiconductor film on an insulator is as follows:
Normal S OS (Silicon On 5apphi)
There is a method of forming a Si semiconductor film on a single crystal sapphire substrate by an epitaxial method, as typified by re). However, in the conventional technology, there is no crystal plane in which the interstitial constant of the grown single crystal seed and the interstitial constant of the substrate sapphire single crystal completely match (it is difficult to keep the difference in lattice constant to a few percent at most). However, the sapphire substrate has the disadvantage of having many crystal defects in the single-crystal grown seed.Furthermore, the sapphire substrate is expensive, and it is difficult to build high-speed semiconductor devices using a single-crystal semiconductor film on such an insulator. Although there is a strong demand for the production of such a film, its practical application has been delayed.The present invention eliminates these drawbacks and enables the production of a semiconductor single crystal film in a very flat state on an insulator with few crystal defects at a low cost. It is an object of the present invention to provide a method for manufacturing a semiconductor substrate for a high-speed semiconductor device.The basic structure of the present invention for achieving the above object is to A single-crystal growth seed made of a second solid single crystal is provided at the part, especially at the end, and a polycrystalline or amorphous seed is provided at least in contact with the solid single-crystal growth seed and covers the first solid surface. Second
forming a substrate on which a film made of the same material or a third solid material film is formed, and while maintaining the substrate at a temperature slightly lower than the melting point of the solid material film, at least the solid single crystal growth seed and the solid material are formed. The material film is irradiated with an energy beam such as an electron beam or a light beam from a portion in contact with the material film, and is moved and scanned while melting, and the solid material film on the first solid surface is melted substantially continuously by the energy beam. The method is characterized in that single crystallization is performed by solidification through a cooling process, and the solid material film is single crystallized on the substrate surface so that the surface thereof is substantially flat. The present invention will be described in detail below using examples. FIG. 1 schematically shows an embodiment of the present invention, in which 1 is a carbon heater, and the heating temperature is 1200°C to 1300°C.
It is maintained by energizing C. A sample is placed on the carbon heater, and most of the single crystal Si substrate 2 is 5
ift film, Six N4 film or Sin, and St,
N, covered with an insulating film 3 such as a two-layer structure film, a part of the insulating film 3 is etched to expose the base single crystal Si substrate 2 at its end, and the exposed single crystal Si The substrate portion is formed as a growing seed portion 4 of single crystal Si. Here, as shown in FIG.
It is a characteristic. By making this surface substantially flat, the single crystal growth seeds that will be formed later will also be substantially flat. Then, a polycrystalline Si film 5 is formed on their surfaces by the CVD method, and a portion of the single crystal growth seed 4 that is continuous with the single crystal 51 substrate 2 that is in contact with the polycrystalline Si film 5 is irradiated with an electron beam or a laser beam. The polycrystalline Si film 5 is partially irradiated with an energy beam 6 such as
By moving the melted polycrystalline Si in the Y direction while melting it at about 400"C, a portion 7 in which the melted polycrystalline Si becomes single crystal during the cooling process grows continuously in the Y direction, forming a polycrystalline Si film 5.
becomes a single-crystal grown seed with a flat surface. The sample substrate may be formed by attaching single-crystal Si, which will become the single-crystal growth seed 12, to the surface of a glass or ceramic substrate 11, such as quartz, or embedded in the substrate 11, using a head cloth glass, etc. When forming the crystalline Si film 13 by the CVD method, the substrate 11 is directly coated with the CD polycrystalline Si film 13.
It is also possible to have a structure in which an insulating film 14 such as a CVD 5tO film is coated thereon. The single-crystal grown seed with a nearly flat surface on the insulator formed in this way becomes a single-crystal film that maintains the crystallinity of the grown seed, has few crystal defects, and is suitable for expensive substrates such as sapphire. However, it is possible to provide a substrate suitable for manufacturing high-speed semiconductor devices at low cost. Furthermore, in the present invention, by making the surfaces of the single crystal growth seed and the insulating film almost flat, a single crystal growth seed with an almost flat surface is formed, so that when semiconductor elements etc. are formed thereon, This allows us to create products with good credibility. As described above, the present invention provides a single-crystal growth seed continuous with the single-crystal St substrate at the end of a single-crystal Sj substrate, and a polycrystalline seed that is at least in contact with the single-crystal growth seed and coated with the single-crystal St substrate. Alternatively, an amorphous Si film is formed. Thereafter, at least the Si film in a polycrystalline or amorphous state is heated to a temperature slightly lower than its melting point, and an energy beam such as an electron beam or a light beam is applied to the edge of the single-crystal St substrate so as to be continuous with the single-crystal Si substrate. Irradiation starts from the SN film on the formed single crystal growth seed and is moved and scanned over the entire Si film, so the Si film itself is maintained at high temperature and the energy beam irradiation prevents single crystallization. This makes it possible to grow homogeneous single-crystal seeds using an energy beam with low power consumption. In addition, the single crystal grown seeds are single crystal S! Since the single crystal 31 was provided at the edge of the substrate so as to be continuous with the substrate, irradiation of the energy beam was started from the polycrystalline or amorphous Si film formed on the single crystal growth seed, and the energy beam was irradiated across the entire Si film. Since P1 is moved and scanned, a single crystal growth seed having a large area can be reliably obtained. Furthermore, since a single-crystal growth seed was provided at the edge of the single-crystal Si substrate so as to be continuous with the single-crystal Sf substrate, this single-crystal growth seed was used to grow polycrystalline or amorphous Si.
When a film is grown as a single-crystal growth seed, the crystal planes of this single-crystal growth seed are aligned with the single-crystal Sf substrate that is the basis for its growth. Even if elements etc. are formed, elements with very similar element characteristics can be formed. Therefore, the reliability of the entire semiconductor device becomes extremely high. 4. Brief description of the drawings FIG. 1 schematically shows an embodiment of the present invention.
FIG. 2 shows a cross-sectional view of another example of the structure of the substrate sample. 1...Carbon heater 2...Single crystal Si substrate 3.14...Insulating film 4.12...Single crystal growth seed portion 5.13...Polycrystalline S1 film 6...Energy beam 7 ...Single crystal growth seed 11...Insulating substrate or higher

Claims (3)

[Claims] (1) A single crystal growth seed made of a second solid single crystal is provided on a part of the first solid surface, the seed is at least in contact with the solid single crystal growth seed, and the first solid surface is covered. A substrate is formed on which a film made of the same material as the second material or a third solid material film is formed in a polycrystalline or amorphous state, and while the substrate is kept at a temperature slightly lower than the melting point of the solid material film, at least the An energy beam such as an electron beam or a light beam is irradiated from the part where the solid single crystal growth seed and the solid material film are in contact with each other, and the seed is melted while moving and scanning;
The solid material film on the first solid surface is substantially continuously melted and solidified into a single crystal by the energy beam, and the solid material film is single crystallized on the substrate surface. A method for producing a single crystal film characterized by: (2) The method for manufacturing a single crystal film according to claim 1, wherein the first solid is an insulator and the single crystal solid material film is a single crystal semiconductor film. (3) The first solid is a Si single crystal substrate on which an insulating film such as a SiO_2 film or a Si_3N_4 film is formed, or an insulating substrate such as SiO_2, and the second solid single crystal is the first solid. A part of the insulating film is removed from the Si single-crystal substrate as a substrate with the exposed part serving as a Si single-crystal growth seed part, and a polycrystalline or amorphous Si film is coated on the substrate, The Si film is made of single crystal S
A method for producing a single crystal film according to claim 1, characterized in that the film is an i-film.