JPS5821817B2 - Manufacturing method of InSb polycrystalline thin film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention mainly focuses on low-noise InS with extremely thin film thickness.
b.Regarding a method for manufacturing a thin film element.

InSb has an excellent galvanomagnetic effect and is applied to magnetic conversion elements such as Hall elements and magnetoresistive elements.

At this time, the InSb film is required to be extremely thin, so physical vapor deposition methods such as vacuum evaporation and sputtering, or chemical vapor deposition methods such as CVD are used to manufacture the InSb film.

However, thin films produced by these methods (approximately 3 to 0.1μ
A thin film with a thickness of about m is used.

) is a polycrystalline film with a crystal grain size of 1 to 20 μmφ and contains many crystal defects.

In order to coarsen the crystal grains and reduce crystal defects, a method of zone melting the InSb film is known.

However, even with this method, the crystal grain size is about 0.5 to 2 µm, and crystal defects cannot be completely removed.

When a magnetoelectric transducer is formed using such an InSb film,
Noise is superimposed on the output.

For example, when a current of 4000 A/d is passed through a Hall element with an InSb film thickness of 2 μm and an element width of 200 μm, the noise level is 2 to 10 μV (deposited InSb film) under the condition of a frequency band of 100 Hz to 10 kHz. 0.
8 to 2 μV (zone melt or uniform melt InSb
membrane).

In addition, the output of such a Hall element has a Hall coefficient of 3.
00-3507/C1 When the signal magnetic field is 10 Gauss, it is about 2.5-2.8 mV.

Therefore, the conventional zone-melted InSb film Hall element has a signal-to-noise ratio (S/N) of 68 to 73 dB.
Moreover, even if a current of 10,000 A/pe were passed through the Hall element, the result was 71 to 75 dB, and it was difficult to obtain a better S/N than this.

The present invention aims to obtain a Hall element with extremely low noise and excellent S/N, and is a method for producing an InSb polycrystalline thin film by zone melting or melting so as to contain certain impurity elements. .

The inventors have investigated the S/
As a result of conducting various experiments to improve N, we found that InSb was
We have discovered a phenomenon in which the S/N is improved by 5 to 6 dB when heat treatment is performed.

Here, the heat treatment under the condition of excessive sb is a method in which a substance containing sb (Sb diffusion source) such as 5b205 is brought into contact with the InSb film to perform zone melting or melting treatment.

Furthermore, under such conditions, Cu s Au s Ag
sZn, Na, Cd, B, Li, Ca2Mg, Pb
, Ba.

It has been discovered that an even better S/N ratio can be obtained by simultaneously diffusing at least one selected from the group of Al and Fe.

In addition, the amount of addition of the above elements is 5×1 as the total amount.
016-1×1018CrrL-3, more preferably 1
x door 7~6 x about 1717 cd.

In this case, sb has a remarkable noise reduction effect, and other elements have a remarkable effect in making the Hall coefficient more uniform and increasing the signal.

The present invention is based on this knowledge, and the present invention is based on this knowledge.
The present invention provides a means for manufacturing an Sb thin film.

In order to diffuse the above elements, the InSb film may be brought into contact with a substance that decomposes and releases the elements while the InSb film is heated, and the elements are diffused into the InSb film.

For this purpose, inorganic substances (diffusion sources) containing the above-mentioned elements, such as their hydroxides, oxides, or thermosetting glasses containing the above-mentioned elements, are suitable.

Note that as a method of bringing the single substances into contact, a vapor deposition method, ion implantation, etc. can also be used.

Furthermore, as a second method, In sb formed by vapor deposition etc.
This is a method in which a substance containing the above element is brought into contact with the front or back surface of a polycrystalline thin film, and then zone melting or melting treatment is performed.

At this time, the method of diffusing the predetermined element may be the method of bringing the above-mentioned substance into contact with it, or the method of incorporating the predetermined element into a protective film (usually an In203 film is used) to prevent the molten In5b from curling due to surface tension. good.

Embodiments of the present invention will be described below.

(1) After treating the InSb film formed by the vapor deposition method with the zone melt method or melting method, a diffusion source is brought into contact with the sb, which releases sb at a predetermined temperature and diffuses into the InSb film.
A method for producing an InSb polycrystalline thin film, the method comprising performing a heating diffusion treatment at a temperature below the melting point of n5b.

(2) InSb polycrystalline thin film formed by vapor deposition
A method for producing an InSb polycrystalline thin film, which comprises bringing a diffusion source into contact with the film and then subjecting it to zone melting or melting treatment.

(3) After processing the In5b polycrystalline thin film formed by the vapor deposition method by the zone melt method or the melting method, a diffusion source of sb and Cu, Au, Ag, Zn, Na, and K are added.

Cd, B, Li, ca2MgyPb, Ba, ALFe
and at least one diffusion source selected from the diffusion sources of the InS.
(b) A method for producing an InSb polycrystalline thin film, which comprises bringing it into contact with a polycrystalline thin film and subjecting it to a heating diffusion treatment at a temperature below the melting point of InSb.

(4) InSb polycrystalline thin film formed by vapor deposition method,
An InSb polycrystal, characterized in that an sb diffusion source is brought into contact with at least one element selected from the element φ diffusion sources other than sb shown in item (3), and then subjected to zone melting or melting treatment. Method of manufacturing thin films.

(5) In the method for manufacturing an InSb polycrystalline thin film described in items (1) to (4) above, the InSb polycrystalline thin film formed by the vapor deposition
5b A method for producing an InSb polycrystalline thin film, characterized in that the thickness of the polycrystalline thin film is 0.1 to 3 μm.

(6) InS described in item (6) above or item (3)
b In the polycrystalline thin film manufacturing method, the above heating diffusion treatment is carried out in 2 steps.
50-4000G (more preferably 300-400℃)
A method for producing an InSb polycrystalline thin film, characterized in that the process is carried out at a temperature of 1 minute or more.

(7) In the method for producing an In5b polycrystalline thin film according to the above item (2), (3) or (4), the above-mentioned Sb, Cu, Zn, Na, Kp'LisCasMg
A method for producing an InSb thin film, characterized in that hydroxides of pBa sAl and Fe are used as diffusion sources.

(8) In the method for producing an InSb polycrystalline thin film as set forth in item (1), item (2), item (3), or item (4) above,
The above Sb, Cu, Au, Ag, Zn, Cd2Mg, Pb
, Al.

A method for producing an InSb polycrystalline thin film, characterized in that a single element of these elements is used as a Fe diffusion source.

(9) Items (1), (2), and (3) above are used as diffusion sources for Sb and B in the method for manufacturing an InSb polycrystalline thin film in item (4). A method for producing an InSb polycrystalline thin film, characterized by using thermosetting glass containing elements.

00) In the method for manufacturing an InSb polycrystalline thin film according to the above item (1), (2), (3) or (4),
A method for producing an In5b polycrystalline thin film, characterized in that an oxide of sb is used as a diffusion source of sb.

Hereinafter, the present invention will be explained in detail with reference to Examples.

Example 1 In this example, first, the effect when only sb is doped into an InSb film will be described.

InSb was deposited on a Dow Corning 7059 glass substrate whose surface had been extremely cleaned by a three-temperature evaporation method, and then uniformly melted in a vacuum at a heating temperature of 550° C. for 1 hour.

Thereafter, the surface of the InSb film was finished flat by puff polishing.

At this time, the thickness of InSb was set to 0.5 to 2 μm.

The surface of the InSb film was chemically etched with a KOH or aqua regia diluent to remove contaminants adhering to the surface.

A compound capable of releasing sb by thermal decomposition and causing it to diffuse into the InSb was deposited on the surface of the uniform mel-InSb film thus formed.

Examples of compounds that serve as a diffusion source for such sb include 5
b205゜5b205・H20s Sb 205・2H
20,5b205・3H20゜5b(OH)3,5b(
OH)5・XH2O, etc. In this example, 5b20
．． A method of immersing it in an aqueous solution or an alcohol solution was used.

The InSb film coated with 5b205 by immersing the In5b film in the solution and then drying was heat-treated in a 10'' Torr vacuum furnace at a temperature in the range of 200 to 500°C for 1 minute to 2 hours.

A Hall element with a width of 200 μm was formed by photoetching the InSb film in which the sb atoms had been diffused in this way, and a current density of 10000 A/(177!), 10 Gau
Hall output and noise were evaluated under the conditions of a ss magnetic field and a frequency band of 100 Hz to 10 kHz.

As a result, it is possible to obtain effects that are almost the same or better than conventional ones with heat treatment in the temperature range of 250 to 4500 C for 1 minute or more, and in particular, heat treatment in the temperature range of 300 to 400 C for about 1 hour can produce S/
The improvement in N was the most remarkable.

Table 1 shows the noise and S/N obtained in the case of a Hall element with an InSb film thickness of 2 μm in which such sb atoms were diffused at each temperature for 1 hour.

As is clear from this example, the noise of the InSb film heat-treated while supplying sb atoms into the InSb film was reduced and the S/N ratio was significantly improved.

Similar effects can be achieved by performing similar processing using the other diffusion sources and the sb diffusion source described above.

Example 2 In this example, s is added to InSb at a temperature below the melting point of In5b.
A solid-phase diffusion method in which B and other impurity elements are simultaneously doped will be described.

InSb was deposited by a three-temperature evaporation method on a substrate in which a Dow Corning 7059 glass film was formed by sputtering on a mirror-finished Ni-Zn ferrite surface, and an In2O3 protective film was formed on the surface. Melt processing was performed.

After that, In2O3 is removed by puff polishing, and In2O3 is removed by puff polishing.
The surface of the 5b film was finished flat.

At this time, the thickness of InSb was set to 0.5 to 3 μm.

The surface of the In5b film was chemically etched in the same manner as in Example 1 to remove contaminants adhering to the surface.

s on the surface of the thus formed zone mel) InSb film.
b and a diffusion source of a predetermined impurity element were deposited.

There are various ways to achieve this, but for sb, in this example, the method is to apply 5b205,
That is, the method described in Example 1 was used.

Regarding other impurity elements, Cu z Na sK, Lt
For sCatMgsBatAlsZntFe, a similar method of depositing a compound serving as a diffusion source was used.

The compounds include Cu (O island. NaOH, K
OH, LiOH, Ca(OH)2. Mg(OH)2゜B
a(OH)2. Al(OH)3. Zn(OH)2. Fe
(OH)s, etc.

The InSb film was immersed in an aqueous or alcoholic solution of the sb compound and these compounds, and then dried.

Also, elements for which it is difficult to obtain compounds, such as Au, Ag
, Cd, Pb, and InS directly by vapor deposition method.
After several tens to hundreds of λ are deposited on the surface of the b film, the above sb
The compound was deposited.

Furthermore, for elements such as B, a thermosetting glass containing sb and B element atoms, which is commercially available as spin-on glass (thermosetting glass manufactured by Emulsiton Co., Ltd.), was applied.

The InSb film coated with sb and an impurity element diffusion source using the method described above was heat-treated in a vacuum furnace at 10-ITorr.

InS with sb and impurity elements diffused in this way
A Hall element having a width of 200 μm was formed on the b film by photoetching, and the Hall output and noise were evaluated under the same conditions as in Example 1.

As a result, the same heating conditions as in Example 1 can be used for the combination of sb atoms and atoms of any other element, especially 30
Heat treatment at 0 to 400°C for about 1 hour resulted in the most significant improvement in S/N.

Table 2 shows that the InSb film thickness is 2 μm by such solid phase diffusion method.
This is the S/N obtained in the case of the Hall element.

As shown in Table 2, the InSb film doped with sb atoms and other atoms has a maximum S/H value of 79 to 80 d, which is the maximum value of S/H obtained when impurities are diffused without supplying sb.
An even higher S/N than B was obtained.

In the above example, InSb was used in an atmosphere of 1O-1Torr.
Although the diffusion treatment was carried out, the treatment may be carried out in an inert gas or in the atmosphere if the surface of the InSb film is coated with a suitable protective film in advance.

In addition, intrinsic diffusion was performed by bringing a material containing sb element and other impurity elements into contact with the InSb film surface.
It is also possible to use a substrate material doped with the desired impurity element, or to form an InSb film on a substrate on which the sb element and other impurity elements have been deposited in advance, and then perform zone melting or melting treatment and diffusion treatment. good.

The method described above is a method in which atoms of the sb element and other desired impurity elements are brought into contact with the front or back surface of the InSb film, and are solid-phase diffused into the InSb film by appropriate heat treatment.

This method has the advantage that the amount of diffusion of sb atoms and other impurity elements can be controlled by controlling the heating temperature and heating time.

Example 3 In the same manner as in Example 2, 2 μm of InSb having a chemical equivalent composition was deposited by the three-temperature method on a substrate having a Dow Corning 7059 glass film coated on ferrite.

After that, sb, which is one of the elements to be diffused, is further reduced to 0.
．． It was deposited to a thickness of 1 μm to form a layered film of InSb and sb.

Then, if one impurity element is Na or K, N
a) After being immersed in a 10% alcoholic solution of OH or KOH and drying, a protective film of n203 was formed and a zone melting process was performed.

Since the InSb film is melted in this zone melt,
Na impurity atoms on the InSb film surface or once InS
b is incorporated into the molecule, resulting in a concentration of 1020CrrL-3 or higher.

However, zone melting has the effect of segregation of impurities, so by repeating zone melting, 5×1016□~1×101
8. It can be purified to an appropriate concentration of -3.

The S/N of the InSb film thus obtained was evaluated in the same manner as in Example 2, and results similar to those in Table 2 obtained in Example 2 were obtained.

This method controls the impurity concentration by repeating zone melting, but in the case of elements such as Cu z Au and Agt, it is possible to control the amount deposited on the InSb film, for example, by controlling the evaporation thickness of the impurity material. , the desired impurity concentration could be obtained with one zone melt.

[Also, it is of course possible to use a substrate doped with a desired impurity element as described in Example 2.

In addition to the external supply method described in this example, methods for supplying sb atoms include an InSb vapor deposition film, a film in which sb is in excess of the chemical equivalent ratio during formation (to the extent that sb does not precipitate during melting). preferable.

) can be formed in advance.

Similar results could be obtained when such a film was used as an InSb thin film to diffuse impurity element atoms other than sb.

As explained above, CusAusAgsZnsNa 5
KsCa, B, Lt*Ca*Mg, PbtBa, ACF
It has been found that polycrystalline InSb films in which diffusion is performed while supplying sb atoms to one or more element atoms of e- have low noise and, together with an increase in RH, have an extremely excellent S/N ratio. I found it.

Although the present invention may be used as a method for manufacturing a photoelectric conversion element using the -PEM effect, it is particularly useful for manufacturing a thin film magnetosensitive element for low signals.

Claims (1)

[Claims] 1. After zone melting or melting treatment is performed on an InSb polycrystalline thin film formed by a vapor deposition method, the thin film is brought into contact with an sb diffusion source and heat treated at a temperature below the melting point of InSb. A method for producing a characterized Insb polycrystalline thin film. 2. The InSb polycrystalline thin film according to claim 1, wherein the thickness of the InSb polycrystalline thin film is 0.1 to 3 μm.
Method for manufacturing Sb polycrystalline thin film. 3 InSb according to claim 1 or 2
In the method for producing polycrystals, the heat treatment is performed at a temperature of 250 to 40
InSb characterized by being carried out at a temperature of 0°C for 1 minute or more
Method for manufacturing polycrystalline thin films. 4 InSb according to claim 1 or 2
In the method for manufacturing a polycrystalline thin film, the heat treatment is performed at a temperature of 300 to
I, characterized by being carried out at a temperature of 400°C for 1 minute or more
Method for manufacturing nSb polycrystalline thin film. 5. Any one of claims 1 to 3, characterized in that at least one of an oxide of sb, a hydroxide of sb, or a thermosetting glass containing sb is used as the sb diffusion source. A method for producing an In5b polycrystalline thin film as described in . 6. A method for producing an InSb polycrystalline thin film formed by vapor deposition, which comprises bringing an sb diffusion source into contact with the InSb polycrystalline thin film and subjecting it to zone melting or melting treatment. 7. Scope of Patent Disclaimers I described in item 6, characterized in that the thickness of the InSb polycrystalline thin film is 0.1 to 3 μm
Method for manufacturing n5b polycrystalline thin film. 8. After zone melting or melting treatment is performed on the InSb polycrystalline thin film formed by the vapor deposition method, the thin film is exposed to an sb diffusion source and Cu, Au, Ag, Zn, Na, K. Cd, B, Li, Ca, Mg, Pb, Ba, Al. 1. A method for producing an InSb polycrystalline thin film, which comprises bringing the film into contact with a diffusion source containing at least one element selected from the group of Fe, and performing heat treatment at a temperature i below the melting point of In5b. 9. The InSb polycrystalline thin film according to claim 8, wherein the InSb polycrystalline thin film has a thickness of 0.1 to 3 μm.
Method for manufacturing Sb polycrystalline thin film. InSb according to claim 8 or 9 of the 710 patent
In the method for producing a polycrystalline thin film, the heat treatment is performed at a temperature of 250 to
In which the process is carried out at a temperature of 400°C for 1 minute or more
Method for manufacturing Sb polycrystalline thin film. 11 5 I described in claim 8 or 9
In the method for manufacturing an nSb polycrystalline thin film, the heat treatment is performed in 3 steps.
A method for producing an InSb polycrystalline thin film, characterized in that the process is carried out at a temperature of 00 to 400°C for 1 minute or more. 12. Claims 8 to 12, characterized in that at least one of sb alone, sb oxide, sb hydroxide, or thermosetting glass containing sb is used as the sb diffusion source. In5 according to any of item 11
b Method for manufacturing polycrystalline thin film. 13 Cu, Zn, Na, Li, Ca, Mg,
Claims 9 to 1 are characterized in that these hydroxides are used as a diffusion source of BaAl and Fe.
2. A method for producing an In5b polycrystalline thin film according to any one of Item 2. 14 Cu, Au, Ag, Zn, Cd, Mg, Pb
. 13. The method for producing an InSb polycrystalline thin film according to any one of claims 8 to 12, characterized in that a simple substance of these elements is used as a diffusion source of Al)Fe. An sb diffusion source and Cu, Au, Ag, Zn, Na, and Cd were added to the InSb polycrystalline thin film formed by the 15 vapor deposition method. A method for producing an InSb polycrystalline thin film, which comprises bringing the film into contact with a diffusion source containing at least one element selected from the group of B, Li, Ca2Mg, Pb, Ba, and Al5Fe, and subjecting it to zone melting or melting treatment. . 16. I according to claim 15, wherein the InSb polycrystalline thin film has a thickness of 0.1 to 3 μm.
Method for manufacturing nSb polycrystalline thin film. 17 above-mentioned Cu, Zn, Na, Li, Ca9Mg. 17. The method for producing an InSb polycrystalline thin film according to any one of claims 15 to 16, characterized in that hydroxides of these elements are used as diffusion sources of Ba, Al, and Fe. 18 Cu, Au, Ag, Zn, Na, Cd, B as a substrate on which to form an InSb polycrystalline thin film. LipCat Claims 15 to 16 characterized in that a substrate doped with at least one element selected from the group of Mg, Pb, Ba, Al, and Fe is used as a diffusion source for the element. A method for producing an InSb polycrystalline thin film according to any one of the above.