JPH03110830A - Doping process of germanium epitaxial film with antimony - Google Patents

Abstract

PURPOSE:To form a high concentration N type doped layer without requiring an ionization evaporator by a method wherein, in case of evaporating germanium, a germanium substrate is held at room temperature or 250 deg.C so as to simultaneously evaporate antimony. CONSTITUTION:In case of evaporating germanium, a germanium substrate is held at room temperature or at 250 deg.C so as to simultaneously evaporate antimony. When the temperature of germanium substrate does not exceed the room temperature,any adsorbed germanium is hardly shifted while when the temperature exceeds 250 deg.C, any adsorbed antimony is apt to be over-shifted to be hardly taken into a germanium epitaxial film. Furthermore, antimony is evaporated simultaneously with the evaporation of germanium so as to dope with antimony in parallel with the epitaxial deposition of germanium. Through these procedures, an N type doped layer can be formed on the germanium epitaxial film assuring a high doping concentration of antimony and eliminating any ionization evaporator.

Description

Detailed Description of the Invention] (11 Objects of the Invention [Industrial Application Field 1] The present invention relates to a method for doping antimony into a germanium epitaxial film, and in particular, the invention relates to a method for doping antimony into a germanium epitaxial film, and in particular, the invention relates to a method for doping antimony into a germanium epitaxial film. The present invention relates to a method of doping antimony into a germanium epitaxial film by simultaneously depositing antimony or depositing only antimony on a germanium substrate prior to germanium deposition.

[Conventional technology 1] Conventionally, this type of antimony doping method involves adding an ionization evaporation device to a vacuum epitaxial growth device (so-called molecular beam epitaxial growth device) to ionize some of the evaporated antimony atoms and doping them onto a germanium substrate. By forming an appropriate electric field between an ionization evaporator and an ionization evaporator, germanium is vapor-deposited and epitaxially grown on a germanium substrate to form a germanium epitaxial film, and the germanium epitaxial film is doped with antimony. was proposed.

[Problems to be solved] However, in the conventional antimony doping method,
(i) There is a disadvantage that an additional ionization evaporation device must be installed, and (iii) the doping concentration of antimony to the germanium epitaxial film is 1019 atoms/
cm 3 or more, and furthermore, it is practically impossible to form an N-type doped layer on the (iii) germanium epitaxial film.

Therefore, the present invention aims to eliminate these drawbacks (i.e., by simultaneously depositing antimony during germanium deposition while holding the germanium substrate at a temperature between room temperature and 250°C, or by depositing only antimony on the germanium substrate prior to germanium deposition). The present invention aims to provide a method for doping antimony into a germanium epitaxial film.

(2) Structure of the invention [Means for solving the problem] The first means for solving the problem provided by the present invention is [a germanium epitaxial layer formed by epitaxially growing germanium by vapor depositing it on a germanium substrate under vacuum. In an antimony doping method in which antimony is doped into a film during or after epitaxial growth, a germanium substrate is maintained at a temperature of room temperature to 250°C during germanium deposition, and antimony is simultaneously deposited. A method for doping antimony into epitaxial films.

A second solution to the problem provided by the present invention is as follows: ``Antimony is added to a germanium epitaxial film formed by epitaxially growing germanium by vapor-depositing germanium under vacuum on a germanium substrate during or after the epitaxial growth. "An antimony doping method for a germanium epitaxial film" characterized in that the germanium substrate is maintained at a temperature of room temperature to 250° C. and antimony is deposited prior to germanium deposition.

[Function] The first step to the germanium epitaxial film according to the present invention
The antimony doping method is an antimony doping method in which a germanium epitaxial film formed by vapor depositing germanium on a germanium substrate under vacuum and epitaxial growth is doped with antimony during or after the epitaxial growth, and in particular, During the vapor deposition of germanium, the germanium substrate is held at a temperature between room temperature and 250°C, and antimony is simultaneously vapor-deposited. The above-mentioned effects are achieved, and furthermore, fiii) the effect of forming an N-type doped layer in the germanium epitaxial film is achieved.

In addition, the second antimony doping method for a germanium epitaxial film according to the present invention is performed on a germanium epitaxial film formed by depositing germanium on a germanium substrate under vacuum and growing it epitaxially, during or after the epitaxial growth. This is an antimony doping method for doping antimony, and in particular, the germanium substrate is maintained at a temperature between room temperature and 250° C. and antimony is deposited prior to germanium deposition. (1v) It serves to facilitate reduction of the thickness of the antimony doped layer.

[Example] Next, the method of doping antimony into a germanium epitaxial film according to the present invention will be specifically described by giving preferred examples thereof. However, the examples described below are described to facilitate or accelerate understanding of the present invention, and are not described to limit the present invention. In other words, each element disclosed in the embodiments described below includes all design changes and equivalent substitutions that fall within the spirit and technical scope of the present invention.

FIG. 1 shows the first experimental results regarding the first embodiment of the method for doping antimony into a germanium epitaxial film according to the present invention.

FIG. 2 shows the results of a second experiment regarding the first example.

FIG. 3 shows the first experimental results regarding the second example.

FIG. 4 shows the second experimental results regarding the second example.

FIG. 5 shows the third experimental results regarding the second example.

FIG. 6 shows the fourth experimental result regarding the second example.

FIG. 7 shows the fifth experimental result regarding the second example.

FIG. 8 shows the sixth experimental result regarding the second example.

1. First, regarding the first embodiment of the method for doping antimony into a germanium epitaxial film according to the present invention,
Its structure and operation will be explained in detail.

First step to germanium epitaxial film according to the present invention
The antimony doping method is an antimony doping method in which a germanium epitaxial film formed by vapor depositing germanium on a germanium substrate under vacuum and epitaxial growth is doped with antimony during or after the epitaxial growth, and in particular, During vapor deposition of germanium, the germanium substrate is maintained at a temperature of room temperature to 250° C., and antimony is simultaneously vapor-deposited.

Here, the reason why the germanium substrate is maintained at room temperature or 250°C is that when the fil germanium substrate reaches a temperature below room temperature, germanium adsorbed on the surface of the germanium substrate or germanium epitaxial film becomes difficult to move. Epitaxial growth is excessively inhibited, and (ii
When the temperature of the germanium substrate exceeds 250℃,
Antimony adsorbed on the surface of the germanium substrate or the surface of the germanium epitaxial film is easy to move (so much so that it becomes difficult to incorporate it into the germanium epitaxial film.Germanium substrates are particularly sensitive to temperatures ranging from room temperature to 150°C). It is preferable if the temperature is maintained at a temperature of 200 to increase the amount of antimony incorporated into the germanium epitaxial film.

Furthermore, the basis for simultaneously depositing antimony during germanium deposition is to dope antimony in parallel to the epitaxial growth of germanium.

Since antimony comes to the surface of the epitaxial film as germanium grows epitaxially, it may be deposited intermittently.

Note that the vacuum is preferably 10-'Torr or more. This is because if the vacuum is less than to-'Torr, impurity atoms (such as oxygen atoms) will be excessively adsorbed on the surface of the germanium substrate or the surface of the germanium epitaxial film, inhibiting the movement of germanium, and thus inhibiting the epitaxial growth of germanium. This is because it will not be possible to achieve good results.

Second Example First, regarding the second embodiment of the method for doping antimony into a germanium epitaxial film according to the present invention,
Its structure and operation will be explained in detail.

The second coating on the germanium epitaxial film according to the present invention
The antimony doping method is an antimony doping method in which a germanium epitaxial film formed by vapor depositing germanium on a germanium substrate under vacuum and epitaxial growth is doped with antimony during or after the epitaxial growth, and in particular, The germanium substrate is maintained at a temperature between room temperature and 250° C., and antimony is deposited prior to germanium deposition.

Here, the reason why antimony is vapor-deposited on the germanium substrate prior to the vapor deposition of germanium is to make use of the phenomenon in which antimony rises to the surface of the epitaxial film during the epitaxial growth of germanium. The purpose is to make it easier to control the wall thickness. If it is desired to incorporate antimony into a predetermined position in the germanium epitaxial film, the temperature of the germanium substrate may be lowered in accordance with the position.

The amount of antimony deposited on the germanium substrate is (f
If it is too small, an N-type doped layer cannot be formed, and if it is too large, epitaxial growth will be inhibited, so it is necessary to set the amount within an appropriate range.

In addition, the germanium substrate is (1,0,01, (1,1
,01.

If the substrate is cut along a plane that makes an angle of less than 10 degrees (preferably 6 degrees) with respect to the main crystal planes such as fl, l, and 11 (referred to as a "slightly inclined substrate"), terraces and terraces can be used. This is preferable because antimony can be adsorbed and taken in by the ledge existing between the two, and the amount and position of antimony to be taken in can be easily controlled.

Other conditions and their basis are the same as in the first embodiment, so they will be omitted.

In addition, the method for doping antimony into a germanium epitaxial film according to the present invention will be described in detail by citing specific numerical values.

A substrate cut out along the main crystal plane fl, 0.01 (referred to as a non-tilted substrate) was used as the proprietary germanium substrate.

After placing the germanium substrate in a vacuum chamber of a molecular beam epitaxial apparatus, the vacuum chamber is made to have a vacuum of 10 = 9 Torr, and the temperature of the germanium evaporation source is the temperature of germanium housed in a Knudsen cell (hereinafter the same shall apply) and the antimony evaporation source. Doping of antimony into the germanium epitaxial film was started by maintaining the temperature of antimony contained in a Knudsen cell at 1250° C. and 260° C., respectively. Here, the epitaxial growth rate of germanilam was set at 50 people/min.

First, a 250-thick germanium epitaxial film was formed on a germanium substrate by simultaneously depositing germanium and antimony while maintaining the temperature of the germanium substrate at 500°C.

Second, by depositing only germanium while maintaining the temperature of the germanium substrate at 300° C., a 750-thick germanium epitaxial film was formed on the germanium substrate.

Third, by simultaneously depositing germanium and antimony while maintaining the temperature of the germanium substrate at 400° C., a 250-thick germanium epitaxial film was formed on the germanium substrate.

Fourth, by depositing only germanium while maintaining the temperature of the germanium substrate at 300° C., a 750-thick germanium epitaxial film was formed on the germanium substrate.

Fifth, by simultaneously depositing germanium and antimony while maintaining the temperature of the germanium substrate at 350° C., a 250-thick germanium epitaxial film was formed on the germanium substrate.

Sixth, by depositing only germanium while maintaining the temperature of the germanium substrate at 300° C., a 750-thick germanium epitaxial film was formed on the germanium substrate.

Seventh, by simultaneously depositing germanium and antimony while maintaining the temperature of the germanium substrate at 300° C., a 250-thick germanium epitaxial film was formed on the germanium substrate.

Eighth, by depositing only germanium while maintaining the temperature of the germanium substrate at 300° C., a 750-thick germanium epitaxial film was formed on the germanium substrate.

Ninth, by simultaneously depositing germanium and antimony while maintaining the temperature of the germanium substrate at 270° C., a 250-thick germanium epitaxial film was formed on the germanium substrate.

Tenth, by depositing only germanium while maintaining the temperature of the germanium substrate at 270° C., a 750-thick germanium epitaxial film was formed on the germanium substrate.

Eleventh, by simultaneously depositing germanium and antimony while maintaining the temperature of the germanium substrate at 230° C., a 250-thick germanium epitaxial film was formed on the germanium substrate.

Twelfth, by depositing only germanium while maintaining the temperature of the germanium substrate at 230° C., a 750-thick germanium epitaxial film was formed on the germanium substrate.

Thirteenth, by simultaneously depositing germanium and antimony while maintaining the temperature of the germanium substrate at 190° C., a 250-layer thick germanium epitaxial film was formed on the germanium substrate.

Fourteenth, by depositing only germanium while maintaining the temperature of the germanium substrate at 190° C., a 750-thick germanium epitaxial film was formed on the germanium substrate.

Fifteenth, by simultaneously depositing germanium and antimony while maintaining the temperature of the germanium substrate at 120° C., a 250-thick germanium epitaxial film was formed on the germanium substrate.

Sixteenth, by depositing only germanium while maintaining the temperature of the germanium substrate at 120° C., a 750-thick germanium epitaxial film was formed on the germanium substrate.

Seventeenth, by simultaneously depositing germanium and antimony while maintaining the temperature of the germanium substrate at 80° C., a 500-thick germanium epitaxial film was formed on the germanium substrate.

The results of doping the germanium epitaxial film on the germanium substrate with antimony through the above vapor deposition process were analyzed using a secondary ion mass spectrometer, and the results were as shown in FIG. In other words, the temperature of the germanium substrate is 2.
At the position corresponding to the temperature below 30° C.), the germanium epitaxial film was doped with a sufficiently large amount of antimony.

As a circular germanium substrate, the main crystal plane f1.0. A substrate (referred to as a non-tilted substrate) cut out along the curve O) was used.

After placing the germanium substrate in a vacuum chamber of a molecular beam epitaxial device, the vacuum chamber was made a vacuum of 10-9 Torr, and the temperature of the germanium substrate was maintained at 190°C.
Then, doping of antimony into the germanium epitaxial film was started while maintaining the temperature of the germanium evaporation source at 1250°C. Here, the germanium epitaxial growth rate was set at 50 people/min.

First, by depositing only germanium, a 600-layer thick germanium epitaxial film was formed on a germanium substrate.

Second, by simultaneously depositing germanium and antimony while maintaining the temperature of the antimony evaporation source at 300°C, a 60-layer thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. .

Third, by depositing only germanium, a germanium epitaxial film with a thickness of 600 mm was additionally formed on the germanium epitaxial film formed on the germanium substrate.

Fourth, by simultaneously depositing germanium and antimony while maintaining the temperature of the antimony evaporation source at 323°C, a 600-layer thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. .

Fifth, by depositing only germanium, a 60-thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate.

Sixth, by simultaneously depositing germanium and antimony while maintaining the temperature of the antimony evaporation source at 340°C, a 60-thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. .

Seventh, by depositing only germanium, a germanium epitaxial film with a thickness of 600 mm was additionally formed on the germanium epitaxial film formed on the germanium substrate.

The results of doping the germanium epitaxial film on the germanium substrate with antimony through the above vapor deposition process were analyzed using a secondary ion mass spectrometer, and the results were as shown in FIG. That is, as the temperature of the antimony evaporation source rose from 300° C. to 340° C., the amount of antimony doped into the germanium epitaxial film increased.

As the germanium substrate, a substrate cut out along the main crystal plane fl, 0.01 (referred to as a non-tilted substrate) was used.

After placing the germanium substrate in a vacuum chamber of a molecular beam epitaxial apparatus, the vacuum chamber was evacuated to 9 Torr, and the germanium epitaxial temperature was maintained at 1250°C and 280°C, respectively, for the germanium evaporation source and the antimony evaporation source. Antimony doping into the membrane was started. Here, the germanium epitaxial growth rate was set at 50 people/min.

First, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., about 10 14 atoms/cm 2 of antimony was adsorbed onto the germanium substrate.

Second, by depositing only germanium while maintaining the temperature of the germanium substrate at 280° C., a 1000-layer thick germanium epitaxial film was formed on the germanium substrate. According to the results of secondary ion mass spectrometry, antimony was not incorporated into the germanium epitaxial film, and no doping layer was formed.

Third, by depositing only germanium while maintaining the temperature of the germanium substrate at 100° C., a 200-layer thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doped layer, and the doping concentration exceeded 1020 atoms/cm3. The half width of the doped layer at this time was about 104.

Fourth, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., about 10 14 atoms/cm 2 of antimony was adsorbed onto the germanium epitaxial film formed on the germanium substrate.

Fifth, by depositing only germanium while maintaining the temperature of the germanium substrate at 250° C., a germanium epitaxial film with a thickness of 1000 μm was formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, antimony was not incorporated into the germanium epitaxial film, and no doping layer was formed.

Sixth, by depositing only germanium while maintaining the temperature of the germanium substrate at 100° C., a 200-thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doping layer, and the doping concentration exceeded 5×10 19 atoms/cm 3 . The half width of the doped layer at this time was about 88.

Seventh, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., about 1014 atoms/cm” of antimony was adsorbed onto the germanium epitaxial film formed on the germanium substrate.

Eighth, by depositing only germanium while maintaining the temperature of the germanium substrate at 230° C., a germanium epitaxial film with a thickness of 1000 nm was formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, a small amount of antimony was incorporated into the germanium epitaxial film, forming a doped layer.

Ninth, by depositing only germanium while maintaining the temperature of the germanium substrate at 100° C., a 200-thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doping layer, and the doping concentration exceeded 5X10+9 atoms/cm. The half-width was about 80 people.

First, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., about 10” atoms/cm” of antimony was adsorbed onto the germanium epitaxial film formed on the germanium substrate.

Eleventh, by depositing germanium while maintaining the temperature of the germanium substrate at 210°C, 1
An additional germanium epitaxial film with a thickness of 1,000 cm was formed. According to the results of secondary ion mass spectrometry, antimony was incorporated into the germanium epitaxial film to form a doping layer, and the doping concentration exceeded 1019 atoms/cm3. The half width of the doped layer at this time was 208.

Twelfth, by depositing only germanium while maintaining the temperature of the germanium substrate at 100° C., a 200-thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doped layer, and the doping concentration reached approximately 1019 atoms/am3. The half width of the doped layer at this time was about 72 layers.

Thirteenth, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., about 10 14 atoms/cm 2 of antimony was adsorbed onto the germanium epitaxial film formed on the germanium substrate.

Fourteenth, by depositing only germanium while maintaining the temperature of the germanium substrate at 190° C., a germanium epitaxial film with a thickness of 1000 nm was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doped layer, and the degree of doping exceeded 5 x 10"atoms/cm".

The half width of the doped layer at this time was 104.

Fifteenth, by depositing only germanium while maintaining the temperature of the germanium substrate at 100° C., a 200-thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, almost no antimony was incorporated into the germanium epitaxial film.

Sixteenth, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., about 1014 atoms/cm” of antimony was adsorbed onto the germanium epitaxial film formed on the germanium substrate.

Seventeenth, by depositing only germanium while maintaining the temperature of the germanium substrate at 150° C., a germanium epitaxial film with a thickness of 1000 μm was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doped layer, and the doping concentration exceeded X020 atoms/cm3. The half width of the doped layer at this time was 80.

Eighteenth, by depositing only germanium while maintaining the temperature of the germanium substrate at 100° C., a 200-thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, almost no antimony was incorporated into the germanium epitaxial film.

Nineteenth, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., about 1014 atoms/cm” of antimony was adsorbed onto the germanium epitaxial film formed on the germanium substrate.

20th, by depositing only germanium while maintaining the temperature of the germanium substrate at 120° C., a germanium epitaxial film with a thickness of 1000 μm was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doped layer, and the doping concentration reached 5 x 10'' atoms/cm3.

The half width of the doped layer at this time was 64.

Twenty-first, by depositing only germanium while maintaining the temperature of the germanium substrate at 100° C., a 200-thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, no antimony was incorporated into the germanium epitaxial film.

The germanium epitaxial film formed on the germanium substrate by the above vapor deposition process was doped with antimony, and the results were analyzed using a secondary ion mass spectrometer as shown in FIG. 3. That is, 1200 people from the surface of the germanium epitaxial film,
2400 people, 3600 people.

The 5000, 6200 and 7400 positions were doped with a sufficiently high amount of antimony in a layer.

A germanium substrate cut along a plane tilted by 2 degrees in the [0,1,1] direction with respect to the main crystal plane (1,0,0) (in other words, a slightly tilted substrate) It was adopted.

After placing the germanium substrate in a vacuum chamber of a molecular beam epitaxial apparatus, the vacuum chamber is evacuated to lo-9 Torr, and germanium epitaxial growth is performed by maintaining the germanium evaporation source temperature and the antimony evaporation source temperature at 1250°C and 280°C, respectively. Antimony doping into the membrane was started. Here, the germanium epitaxial growth rate was set at 50 people/min.

First, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., about 1014 atoms/cm” of antimony was adsorbed onto the germanium substrate.

Second, by depositing only germanium while maintaining the temperature of the germanium substrate at 280° C., a 1000-layer thick germanium epitaxial film was formed on the germanium substrate. According to the results of secondary ion mass spectrometry, antimony was not incorporated into the germanium epitaxial film, and no doping layer was formed.

Third, by depositing only germanium while maintaining the temperature of the germanium substrate at 100° C., a 200-layer thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doping layer, and the doping concentration exceeded 1022 atoms/Cm. The half-width was about 114 people.

Fourth, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., about 1014 atoms/cm” of antimony was adsorbed onto the germanium epitaxial film formed on the germanium substrate.

Fifth, by depositing only germanium while maintaining the temperature of the germanium substrate at 230° C., a germanium epitaxial film with a thickness of 1000 μm was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, antimony was incorporated into the germanium epitaxial film to form a doping layer, and the doping concentration was about 1018 atoms/cm3. The half width of the doped layer at this time was about 107.

Sixth, by depositing only germanium while maintaining the temperature of the germanium substrate at 100° C., a 200-thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doped layer, and the doping concentration exceeded 101 g atoms/Cm3. The half width of the doped layer at this time was about 69 layers.

Seventh, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., about 1014 atoms/cm2 of antimony was adsorbed onto the germanium epitaxial film formed on the germanium substrate.

Eighth, by depositing germanium while maintaining the temperature of the germanium substrate at 210°C, the germanium epitaxial film formed on the germanium substrate was
A germanium epitaxial film with a thickness of 0.00000000 was additionally formed. According to the results of secondary ion mass spectrometry, antimony is incorporated into the germanium epitaxial film to form a doping layer, and the doping concentration is x.
It was about 18 atoms/cm3. The half width of the doped layer at this time was about 380 people.

Ninth, by depositing only germanium while maintaining the temperature of the germanium substrate at 100° C., a 200-thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, antimony was incorporated into the germanium epitaxial film to form a doping layer, and the doping concentration exceeded 101l' atoms/cm. The half-width was about 76 people.

Tenth, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., about 1014 atoms/ρm2 of antimony was adsorbed onto the germanium epitaxial film formed on the germanium substrate.

Eleventh, by depositing only germanium while maintaining the temperature of the germanium substrate at 190° C., a germanium epitaxial film with a thickness of 1000 μm was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doped layer, and the doping concentration exceeded 101 g atoms/cm3. The half width of the doped layer at this time was about 107.

Twelfth, by depositing only germanium while maintaining the temperature of the germanium substrate at 100° C., a 200-thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, antimony was not incorporated into the germanium epitaxial film, and no doping layer was formed.

Thirteenth, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., about 10 14 atoms/cm 2 of antimony was adsorbed onto the germanium epitaxial film formed on the germanium substrate.

Fourteenth, by depositing only germanium while maintaining the temperature of the germanium substrate at 150° C., a germanium epitaxial film with a thickness of 1000 μm was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doping layer, and the doping concentration exceeded 1020 atoms/cm. The half-width was about 69 people.

Fifteenth, by depositing only germanium while maintaining the temperature of the germanium substrate at 100° C., a 200-thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, antimony was not incorporated into the germanium epitaxial film, and no doping layer was formed.

Sixteenth, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., about IO+4 atoms/cm” of antimony was adsorbed onto the germanium epitaxial film formed on the germanium substrate.

Seventeenth, by depositing only germanium while maintaining the temperature of the germanium substrate at 120° C., a germanium epitaxial film with a thickness of 1000 μm was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doping layer, and the doping concentration reached 1022 atoms/cm3. The half width of the doped layer at this time was about 50.

Eighteenth, by depositing only germanium while maintaining the temperature of the germanium substrate at 100° C., a 200-thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, antimony was not incorporated into the germanium epitaxial film, and no doping layer was formed.

The germanium epitaxial film formed on the germanium substrate through the above vapor deposition process was doped with antimony, and the results were analyzed using a secondary ion mass spectrometer as shown in FIG. 4. That is, 1200 people from the surface of the germanium epitaxial film,
2400 people, 3600 people.

The 5000 and 6200 positions were doped with a sufficiently large amount of antimony as described above.

Yutaka Kase 1 A substrate cut out along the main crystal planes (1, 0, 0+ (referred to as a non-tilted substrate) was used as the germanium substrate.

After placing the germanium substrate in a vacuum chamber of a molecular beam epitaxial apparatus, the vacuum chamber is evacuated to 1O-9 Torr, and germanium epitaxial growth is performed by maintaining the germanium evaporation source temperature and the antimony evaporation source temperature at 1250°C and 280°C, respectively. Antimony doping into the membrane was started. Here, the germanium epitaxial growth rate was set at 50 people/min.

First, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., about 10'3 atoms/cm'' of antimony was adsorbed onto the germanium substrate.

Second, by depositing only germanium while maintaining the temperature of the germanium substrate at 280° C., a germanium epitaxial film with a thickness of 1800 mm was formed on the germanium substrate. According to the results of secondary ion mass spectrometry, antimony was not incorporated into the germanium epitaxial film, and no doping layer was formed.

Third, by depositing only germanium while maintaining the temperature of the germanium substrate at 100° C., a 200-layer thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doped layer, and the doping concentration exceeded 5×10 ``atoms/cm''. The half width of the doped layer at this time was about 59 layers.

Fourth, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., about 1012 atoms/cm” of antimony was adsorbed onto the germanium epitaxial film formed on the germanium substrate.

Fifth, by depositing only germanium while maintaining the temperature of the germanium substrate at 280° C., a germanium epitaxial film with a thickness of 1800 mm was formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, antimony was not incorporated into the germanium epitaxial film, and no doping layer was formed.

Sixth, by depositing only germanium while maintaining the temperature of the germanium substrate at 100° C., a 200-thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doped layer, and the doping concentration exceeded 10I8 atoms/cm'. The half width of the doped layer at this time was about 68.

Seventh, by depositing only germanium while maintaining the temperature of the germanium substrate at 280° C., a 600-layer thick germanium epitaxial film was formed on the germanium epitaxial film formed on the germanium substrate.

Eighth, by depositing only germanium while maintaining the temperature of the germanium substrate at 100° C., a 200-thick germanium epitaxial film was additionally formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doped layer, and the doping concentration exceeded 1018 atoms/cm3. The half width of the doped layer at this time was about 10.

The germanium epitaxial film formed on the germanium substrate by the above vapor deposition process was doped with antimony, and the results were analyzed using a secondary ion mass spectrometer as shown in FIG. 5. That is, 100 people from the surface of the germanium epitaxial film, 1
A sufficiently large amount of antimony was doped in layers for the 000 and 3000 positions.

A substrate (referred to as a non-tilted substrate) cut out along the main crystal planes (1, 0, 01) was used as the germanium substrate.

After placing the germanium substrate in a vacuum chamber of a molecular beam epitaxial apparatus, the vacuum chamber is evacuated to lo-9 Torr, and germanium epitaxial growth is performed by maintaining the germanium evaporation source temperature and the antimony evaporation source temperature at 1250°C and 280°C, respectively. Antimony doping into the membrane was started. Here, the germanium epitaxial growth rate was set at 50 people/min.

First, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., about 1014 atoms/cm” of antimony was adsorbed onto the germanium substrate.

Second, by depositing only germanium while maintaining the temperature of the germanium substrate at 270° C., a 290-thick germanium epitaxial film was formed on the germanium substrate. Germanium epitaxial film has
According to the results of secondary ion mass spectrometry, antimony was not incorporated and no doping layer was formed.

Thirdly, by depositing only germanium while maintaining the temperature of the germanium substrate at 90°C, 2
An additional germanium epitaxial film with a thickness of 0.000 cm was formed. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doping layer, and the doping concentration was about 4xlQ19 atoms/cm'. The half width of the doped layer at this time was about 58 layers.

Fourth, by depositing only germanium while maintaining the temperature of the germanium substrate at 280° C., a germanium epitaxial film with a thickness of 290 mm was formed on the germanium epitaxial film formed on the germanium substrate. According to the results of secondary ion mass spectrometry, antimony was not incorporated into the germanium epitaxial film, and no doping layer was formed.

The results of doping the germanium epitaxial film formed on the germanium substrate with antimony through the above vapor deposition process were analyzed using a secondary ion mass spectrometer, and the results were as shown in FIG. That is, a sufficiently large amount of antimony was doped in a layer at 300 positions from the surface of the germanium epitaxial film.

As the germanium substrate, a substrate cut out along the main crystal plane fl, 0.01 (referred to as a non-tilted substrate) was used.

After placing the germanium substrate in a vacuum chamber of a molecular beam epitaxial apparatus, the vacuum chamber is evacuated to lo-9 Torr, and germanium epitaxial growth is performed by maintaining the germanium evaporation source temperature and the antimony evaporation source temperature at 1250°C and 280°C, respectively. Antimony doping into the membrane was started. Here, the germanium epitaxial growth rate was set at 50 people/min.

First, by depositing only antimony while maintaining the temperature of the germanium substrate at 200° C., about 10” atoms/cm” of antimony was adsorbed onto the germanium substrate.

Second, by depositing germanium while maintaining the temperature of the germanium substrate at 200°C, we deposited germanium on the germanium epitaxial film formed on the germanium substrate.
A germanium epitaxial film with a thickness of 0.00000000 was additionally formed. According to the results of secondary ion mass spectrometry, antimony is incorporated into the germanium epitaxial film to form a doping layer, and the doping concentration is 1.
It exceeded 0.017 atoms/clT13.

Thirdly, by depositing only germanium while maintaining the temperature of the germanium substrate at 90°C, 2
A germanium epitaxial film with a thickness of 50 people was additionally formed. According to the results of secondary ion mass spectrometry, a large amount of antimony was incorporated into the germanium epitaxial film to form a doped layer, and the doping concentration exceeded approximately 1019 atoms/cm''.

The germanium epitaxial film formed on the germanium substrate by the above vapor deposition process was doped with antimony, and the results were analyzed using a secondary ion mass spectrometer as shown in Figure 7. That is, a sufficiently large amount of antimony was doped in layers at positions 220 and 4220 from the surface of the germanium epitaxial film.

As a flame-filled germanium substrate, a substrate cut along a plane inclined by 2 degrees toward the [0,1,1] direction with respect to the main crystal plane (1,0,01 (i.e., referred to as a slightly inclined substrate) is used. Adopted.

After placing the germanium substrate in a vacuum chamber of a molecular beam epitaxial apparatus, the vacuum chamber is evacuated to 1O-9 Torr, and germanium epitaxial growth is performed by maintaining the germanium evaporation source temperature and the antimony evaporation source temperature at 1250°C and 280°C, respectively. Antimony doping into the membrane was started. Here, the germanium epitaxial growth rate was set at 50 people/min.

First, by depositing only antimony while maintaining the temperature of the germanium substrate at 280° C., antimony was deposited on the germanium substrate to an extent of about 10” atoms/cm 2 .

Second, by depositing germanium while maintaining the temperature of the germanium substrate at 200°C, we deposited germanium on the germanium epitaxial film formed on the germanium substrate.
A germanium epitaxial film with a thickness of 0.00000000 was additionally formed. According to the results of secondary ion mass spectrometry, antimony is incorporated into the germanium epitaxial film to form a doping layer, and the doping concentration is 1.
It was about 0.018 atoms/cm''.

Thirdly, by depositing only germanium while maintaining the temperature of the germanium substrate at 90°C, 2
A germanium epitaxial film with a thickness of 50 people was additionally formed. According to the results of secondary ion mass spectrometry, antimony is incorporated into the germanium epitaxial film to form a doping layer, and the doping concentration is 1.
It exceeded 0.019 atoms/cm3.

The germanium epitaxial film formed on the germanium substrate by the above vapor deposition process was doped with antimony, and the results were analyzed using a secondary ion mass spectrometer as shown in FIG. 8. That is, as described above, a sufficiently large amount of antimony was doped in a layer at positions 220 and 4220 from the surface of the germanium epitaxial film.

Example 9 A substrate (referred to as a non-tilted substrate) cut out along the main crystal planes (1, 0, 01) was used as the germanium substrate.

After placing the germanium substrate in a vacuum chamber of a molecular beam epitaxial apparatus, the vacuum chamber is evacuated to 1O-9 Torr, and germanium epitaxial growth is performed by maintaining the germanium evaporation source temperature and the antimony evaporation source temperature at 1250°C and 260°C, respectively. Antimony doping into the membrane was started. Here, the germanium epitaxial growth rate was set at 50 people/min.

By simultaneously depositing germanium and antimony while maintaining the temperature of the germanium substrate at 180°C,
A germanium epitaxial film with a thickness of 8,253 layers was formed on a germanium substrate.

When the polarity of the Hall voltage of the germanium epitaxial film was measured, it was found that the doped layer was N-type.

A substrate cut out along the main crystal planes (1, 0, 01) (referred to as a non-tilted substrate) was used as the blood plate and germanium substrate.

After placing the germanium substrate in a vacuum chamber of a molecular beam epitaxial apparatus, the vacuum chamber is evacuated to 1O-9 Torr, and germanium epitaxial growth is performed by maintaining the germanium evaporation source temperature and the antimony evaporation source temperature at 1250°C and 280°C, respectively. Antimony doping into the membrane was started. Here, the germanium epitaxial growth rate was set at 50 people/min.

By simultaneously depositing germanium and antimony while maintaining the temperature of the germanium substrate at 180°C,
A germanium epitaxial film with a thickness of 8,532 layers was formed on a germanium substrate.

When the polarity of the Hall voltage of the germanium epitaxial film was measured, it was found that the doped layer was N-type.

A substrate cut out along the main crystal planes (1, 0, 01 (referred to as a non-tilted substrate) was used as the germanium substrate.

After placing the germanium substrate in a vacuum chamber of a molecular beam epitaxial apparatus, the vacuum chamber is evacuated to 1O-9 Torr, and the germanium evaporation source temperature and the antimony evaporation source temperature are maintained at 1250°C and 300°C, respectively. We have started doping antimony into epitaxial films. Here, the germanium epitaxial growth rate was set at 50 people/min.

By simultaneously depositing germanium and antimony while maintaining the temperature of the germanium substrate at 180°C,
A germanium epitaxial film with a thickness of 8,538 layers was formed on a germanium substrate.

When the polarity of the Hall voltage of the germanium epitaxial film was measured, it was found that the doped layer was N-type.

A substrate cut out along the main crystal plane f1, 0.01 (referred to as a non-tilted substrate) was used as the germanium substrate.

After placing the germanium substrate in a vacuum chamber of a molecular beam epitaxial apparatus, the vacuum chamber is evacuated to 10-'' Torr, and the germanium evaporation source temperature and the antimony evaporation source temperature are maintained at 1250°C and 320°C, respectively. Antimony doping into the epitaxial film was started, where the germanium epitaxial growth rate was set at 50 people/min.

By simultaneously depositing germanium and antimony while maintaining the temperature of the germanium substrate at 180°C,
A germanium epitaxial film with a thickness of 8,062 layers was formed on a germanium substrate.

When the polarity of the Hall voltage of the germanium epitaxial film was measured, it was found that the doped layer was N-type.

(3) Effects of the invention As is clear from the above, the first antimony doping method for a germanium epitaxial film according to the present invention is a germanium epitaxial film formed by epitaxially growing germanium by vapor depositing germanium on a germanium substrate under vacuum. This is an antimony doping method in which antimony is doped into a film during or after epitaxial growth, and in particular, the germanium substrate is held at a temperature between room temperature and 250°C during germanium deposition, and antimony is simultaneously deposited. (It has the effect of eliminating the antimony ionization evaporation device of the special structure, and (11) the doping concentration of antimony is 1019 atoms/
cm3 or more, and furthermore, it has the effect of forming a (iii) germanium epitaxial N-type doped layer.

In addition, the second antimony doping method for a germanium epitaxial film according to the present invention is performed on a germanium epitaxial film formed by depositing germanium on a germanium substrate under vacuum and growing it epitaxially, during or after the epitaxial growth. This is an antimony doping method for doping antimony, in particular, in which a germanium substrate is maintained at a temperature between room temperature and 250° C. and antimony is deposited prior to germanium deposition. fivl This has the effect of making it easier to reduce the thickness of the antimony doped layer.

[Brief explanation of drawings]

FIG. 1 shows the first experimental results related to the first embodiment of the antimony doping method for a germanium epitaxial film according to the present invention, and FIG. 2 shows the second experimental results related to the first embodiment.
3 shows the first experimental results for the second example, FIG. 4 shows the second experimental results for the second example, and FIG. 5 shows the first experimental results for the second example. Experimental results of 3.
FIG. 6 shows the fourth experimental results for the second example, and the seventh
The figure shows the fifth experimental result regarding the second example, and FIG. 8 shows the sixth experimental result regarding the second example.

Claims (3)

[Claims] (1) In an antimony doping method, a germanium epitaxial film formed by epitaxially growing germanium by vapor depositing germanium under vacuum on a germanium substrate is doped with antimony during or after the epitaxial growth. 1. A method for doping antimony into a germanium epitaxial film, which method comprises simultaneously depositing antimony while maintaining the temperature between room temperature and 250°C. (2) In an antimony doping method in which antimony is doped during or after the epitaxial growth of a germanium epitaxial film formed by epitaxially growing germanium by vapor deposition on a germanium substrate under vacuum, the germanium substrate is 1. A method for doping antimony into a germanium epitaxial film, the method comprising depositing antimony while maintaining the film at a temperature between room temperature and 250°C. (3) The method for doping antimony into a germanium epitaxial film according to claim (2), wherein the germanium substrate is a slightly inclined substrate.