JPH0435022A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To form an excellent P-type conductivity type semiconductor region in a short time by depositing aluminum on the main surface of a semiconductor substrate by a CVD method using gas of alkylaluminum halide and hydrogen, and diffusing aluminum in the substrate. CONSTITUTION:A part to be formed with a P-type diffused region is removed on an n-type single crystalline Si substrate 201 of a semiconductor substrate, and an insulating film 202 is provided so as to expose the surface of the substrate 201. The base surface of an electron doner is heated to a temperature of decomposing temperature or higher of alkylaluminum halide and 440 deg.C or lower with mixture gas of gas of the alkylaluminum halide and hydrogen gas to deposit a single crystal Al 203 on the base, heat treated to diffuse Al from the crystal Al 203 into the substrate 201 to form a P-type diffused region 204. This crystal has excellent crystallinity on the surface, and almost no alloy spike occurs upon formation of an eutectic crystal on an Al-Si boundary with the semiconductor substrate.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing semiconductor devices such as memory photoelectric conversion devices and signal processing devices installed in various electronic devices, and particularly relates to a method for manufacturing semiconductor devices of P-type conductivity type. It is about law.

[Prior art]

As a method for forming a P-type semiconductor region in a semiconductor device,
Generally, boron (B) is incorporated into a semiconductor by thermal diffusion or ion implantation to impart P-type conductivity. However, when forming a desired P-type semiconductor layer in a short time by a low-temperature process, it has not always been possible to obtain a satisfactory P-type semiconductor when B is used as an impurity element. This means that in such a short time, silicon (Si
) is believed to be due to insufficient diffusion of B into the substrate.

Therefore, the diffusion coefficient of semiconductor impurities into a substrate made of silicon is one order of magnitude larger than that of aluminum (A).
j2) A method of using atoms as semiconductor impurity atoms to control conductivity has been considered. A conventional method of forming a P-type region using such eight ρ will be described below with reference to FIG.

FIG. 7 is a schematic cross-sectional view for explaining the process.

After preparing a single crystal SL substrate 701 and forming a silicon oxide layer 702 by thermal oxidation, this is patterned to form an opening 703. (Figure 7 (A)) Next, A
Polycrystalline film with a film thickness of 100 to 1000 by depositing ρ, M2
A film 704 is formed. (FIG. 7(B)) Then, the polycrystalline Al2 film 704 is patterned to remove unnecessary portions of the polycrystalline +1 on the silicon oxide layer 702. (FIG. 7(C)) Thereafter, heat treatment is performed to diffuse A.degree. C. into the Si, thereby forming an Si layer containing Afl, that is, a P-type semiconductor region 705. (FIG. 7(D)) [Problem to be solved by the invention] However, in the above conventional example, when depositing A°C,
The characteristics of the -Si interface were not favorable. That is, A
An abnormal diffusion of /l, called an alloy spike, occurs due to the eutectic formation of ρ and the underlying silicon, making it difficult to form a good diffusion layer. Furthermore, in the past, in order to deposit Afl over the entire surface of the wafer, it was necessary to pattern the deposited polycrystalline AI2 using photolithography or the like, which was an obstacle to simplifying the process.

[Object of the Invention] The object of the present invention was made in view of the above-mentioned technical problems, and it is possible to manufacture a semiconductor device having a high-quality P-type semiconductor region at a low cost in order to provide a high-performance semiconductor device at a low price. An object of the present invention is to provide a method for manufacturing a semiconductor device.

Another object of the present invention is to provide a method for manufacturing a semiconductor device that is suitable for low-temperature processes and can form a good P-type semiconductor region in a short time.

Another object of the present invention is to provide a method for manufacturing a semiconductor device that has a simpler manufacturing process than the conventional method.

[Means for Solving the Invention] The present invention was completed as a result of intensive research to solve the problems of the prior art. A method for manufacturing a semiconductor device having a semiconductor region, characterized in that a single crystal aluminum layer is formed on a main surface of a semiconductor substrate, and aluminum is diffused into the semiconductor substrate to form the P-type conductivity type semiconductor region. This is a method for manufacturing a semiconductor device having a P-type conductivity type semiconductor region, in which aluminum is deposited on the main surface of a semiconductor substrate by a CVD method using an alkyl aluminum hydride gas and hydrogen. This method of manufacturing a semiconductor device is characterized in that the P-type conductivity type semiconductor region is formed by depositing aluminum and diffusing aluminum into the semiconductor substrate.

[Function] According to the present invention, by using a high-quality single-crystal Al2 film as the Al2 film formed on the main surface of the semiconductor substrate, a good Al2-semiconductor interface without any hemispikes etc. can be formed, and a good Al2-semiconductor interface can be formed. P
A type diffusion layer can be formed. In addition, by using the CVD method using alkyl aluminum hydride gas and hydrogen as a method for forming single crystal AI2, it is possible to selectively grow Aρ on Si with very good reproducibility. The A4 patterning process is no longer necessary.

[Example] A preferred embodiment of the present invention, when forming a P-type conductivity type semiconductor region, has good selectivity (and almost eliminates the formation of alloy pikes) at a desired position of a semiconductor substrate where the P-type conductivity type semiconductor region is to be formed. Al2 with good crystallinity that does not cause
A P-type semiconductor region is obtained by forming a single crystal Afl as a single crystal Aj2 and diffusing Aρ into a semiconductor substrate using this single crystal Aj2.

FIG. 1 is a schematic diagram for explaining the above embodiment according to the present invention. The thickness of the Al2 layer formed for diffusion is appropriately selected depending on the conductivity and layer thickness of the P-type semiconductor layer to be formed. Approximately 1,000 people is desirable, especially 100 people or more.
Preferably 1000 people. Further, diffusion of Aβ atoms from the formed Afl into the semiconductor layer is performed by heat treatment after the deposition treatment. The temperature of the heat treatment in the diffusion process is
It is selected depending on the type semiconductor layer, but preferably 500'
In order to shorten the boiling point temperature of C-, lf2 and the processing time, it is preferably 800°C to 950''C. This is because it is not possible to obtain a P-type semiconductor region with a thickness lower than G' and sufficiently thick to be used as a semiconductor device.

This diffusion step may be performed, for example, after film formation by stopping the source gas and reaction gas, raising the heating temperature with a lamp, and setting a new one, or continuing with the film formation process. The diffusion process may be performed at different locations.

By the method described above, a P-type semiconductor region 104 is formed on the main surface of the Si substrate 101 by diffusing A° C. by thermal diffusion from the single crystal Af 1103 deposited in the opening formed by the insulating film 102. ing. Further, the Aj2 film 103 remains on the P-type semiconductor region 104.

In this way, by using Aj2, which has a larger diffusion coefficient than boron, as an impurity in the semiconductor, the thrust can be improved. In addition, the manufacturing process can be simplified since it is possible to form an AI2 single crystal with selectivity. Furthermore, since Aj2 can be diffused from a single crystal with good crystallinity into the semiconductor layer, a good P-type diffusion layer can be obtained.

In addition, the deposited film forming method used in the present invention to form such an 8ρ with good crystallinity uses an alkyl aluminum hydride gas and hydrogen gas, and deposits the electron donor on the substrate surface under a mixed gas of these. by heating and depositing a good quality A on the substrate.
℃ deposited film is formed by a surface reaction, and the substrate surface temperature at this time is preferably above the decomposition temperature of the alkyl aluminum hydride and below 450°C, more preferably between 260°C and 440°C (hereinafter referred to as Aj2-C).
This method is called the VD method, and its details will be described later).

In this method, free electrons are present in the substrate surface of the electron donor, or free electrons are intentionally generated on the surface of the substrate, and electrons are exchanged with raw material gas molecules attached to the surface. It takes advantage of the fact that chemical reactions are accelerated.

Therefore, A° C. is deposited with good selectivity only on the electron-donating substrate. In addition, Aj formed by this Afl-CVD method
Since the 2 single crystal has extremely good crystallinity with almost no hillocks on the surface, alloy spikes due to eutectic formation that conventionally occur at the Aj2-8L interface at the interface with the semiconductor substrate hardly occur. Very few. This can produce effects that overturn the conventional concept of AI2.

FIG. 2 is a schematic cross-sectional view for explaining the method of manufacturing a semiconductor device according to the present invention.

For example, on an n-type single crystal Si substrate 201 as a semiconductor substrate, a portion where a P-type diffusion region is to be formed is selectively removed, and an insulating film 202 is formed so that the surface of the substrate 201 as an electron-donating surface is exposed. is provided. This insulating film 2
02 is a non-electron donating surface.

(Figure 2 (A)) By applying the A℃-CVD method to such a substrate, single crystal Aβ
203 is selectively deposited. (Fig. 2 (B)) Next, heat treatment is performed to form Si from single crystal A, f2203.
A, +2 is diffused into the substrate 201. (Figure 2 (C)
) After forming the desired P-type diffusion region 204, if an electrode 205 is formed as necessary, electrical contact can be made with the P-type diffusion region. (FIG. 2(D)) (Description of A° C.-CVD method) According to the A° C.-CVD method, Aβ with good crystallinity can be deposited on an electron-donating surface.

In particular, if this AβCVD method is applied to a substrate in which electron-donating surface portions and non-electron-donating surface portions coexist, AβCVD can be applied to only the electron-donating surface portions of the substrate with good selectivity. Single crystals can be formed.

This electron-donating material is one in which free electrons exist in the substrate, or in which free electrons are intentionally generated. A material with a surface that promotes for example.

Conductors and semiconductors generally correspond to this. It also includes those in which an extremely thin oxide film exists on the surface of a metal or semiconductor as a conductor. Chemical reactions are accelerated by
This is because a chemical reaction occurs between the substrate and the attached raw material molecules due to electron exchange.

Specific electron-donating materials include semiconductors such as single crystal silicon, polycrystalline silicon, and amorphous silicon, Ga, In, and Al2 as group III elements, and P as group V elements;
It is a three-element or three-element or four-element III-V group compound semiconductor formed by combining As and N, or a metal, an alloy, a silicide, or the like. On the other hand, Al2
Alternatively, as a material forming a surface on which a metal containing Al2 as a main component is not selectively deposited, that is, a non-electron-donating material, silicon oxide by thermal oxidation, CVD, etc., or BSG.

Glass such as PSG, BPSG, oxide film, thermal nitride film,
A silicon nitride film or the like is formed by plasma CVD, low pressure CVD, ECR-CVD, or the like.

As the raw material gas, monomethylaluminum hydride (MMAH) or dimethylaluminum hydride (DMAH) is used as the alkylaluminide.
Use.

Hydrogen is used as the reaction gas.

Further, in the present invention, heating of the surface of the substrate is performed by a direct heating method (a method in which energy from a heating means is directly transmitted to the substrate to heat the substrate itself) or an indirect heating method.

Examples of direct heating methods include lamp heating using a halogen lamp, xenon lamp, or the like. In addition, there is resistance heating as a method of indirect heating, which is carried out using a heating element etc. provided on a substrate support member disposed in a space for forming a deposited film to support a substrate on which a deposited film is to be formed. I can do it.

The temperature of the substrate surface during Aβ selection volume is desirably kept at a temperature above the decomposition temperature of the alkyl aluminum hydride and below 450°C, more preferably between 260°C and 440°C. In particular, if the substrate is maintained at the above temperature by direct heating, a high quality ρ film can be formed at a high deposition rate. For example, when the substrate surface temperature during Aρ film formation is set to a more preferable temperature range of 260°C to 440°C, a film deposition rate of 3000 to 5000 people/min can be obtained, and the volume is higher than that in the case of resistance heating. A high quality single crystal A°C film can be obtained at high speed.

Next, an example of a film forming apparatus preferable for applying the Al1-CVD method is shown in FIG. 3 and will be described.

310a to 310d in FIG. 3 are mechanical gate valves, 316a to 316c are exhaust means, and 311.31
3 is a load lock chamber, 318 is a substrate support, 319 is a source gas introduction line, 330 is a lamp as a direct heating means, 331 is a claw on which the substrate is placed, 319' is a reaction gas introduction line, and 319-1 is a This is a bubbler for bubbling A°C (CH3) 2H (DMAH) as alkyl aluminum hydride.

The procedure for forming a film on the substrate is as follows.

First, a base body provided with an insulating film having an opening is placed in the load lock chamber 311 . This load lock chamber 311
A reaction gas is introduced into the reaction gas atmosphere. Next, the inside of the reaction chamber 312 is pumped with lXl by the exhaust system 316b.
Exhaust to about 0-8 Torr.

However, Aβ can be formed into a film even if the degree of vacuum in the reaction chamber 312 is worse than 1×10 To'rr.

Then, the base body is moved and placed on the claw 331.

Raw material gas is supplied from the first gas line 319. The second gas line 319' is for the reactant gas;
The carrier gas H2 is flowed from the gas line 319' of the reaction chamber 31, and the opening degree of a slow leak valve (not shown) is adjusted.
Set the pressure inside 2 to a predetermined value. The preferred pressure in this case is approximately 1.5 Torr. Raw material gas is introduced into the reaction tube from the raw material gas line. The total pressure is preferably 0.05
~760 Torr, more preferably 0.1~0.
8 Torr, and the raw material gas partial pressure is preferably 1X10-5 to 1.3X10 Torr, which is the internal pressure of the reaction tube. Thereafter, electricity is applied to the lamp 330, a heating element (not shown) provided on the base support member, etc., to directly heat the wafer. In this way, A° C. is deposited. After a predetermined deposition time has elapsed, the supply of source gas is temporarily stopped.

With this method, the A4 film is selectively deposited within the openings.

After the above Ag deposition is completed, the CVD reaction chamber 312 is closed to the exhaust system 31.
6b until it reaches a vacuum level of approximately 5×10” Torr or less.The load lock chamber 313 is evacuated by approximately 5×
After exhausting to 1O-3 TOrr or less, the gate valve 31
Open 0C and move the substrate. After closing the gate valve 310C, a gas such as N2 flows into the load lock chamber 313 until it reaches atmospheric pressure, and the substrate is moved out of the apparatus through the gate valve 310d.

According to the present Aρ-CVD method, in addition to forming a P-type diffusion region, it is also possible to selectively deposit a metal film mainly composed of Ar2 as shown below, and to form an electrode that exhibits excellent film characteristics. becomes possible.

For example, in addition to alkyl aluminum hydride gas and hydrogen, S I H4S], 2 H6Si3
H8,Si (CH3)4.5iCfi4+S I
Gas containing Si atoms such as H2Cρz, 5iHCρ3,
Gas containing Ti atoms such as TiCj2+ TiBrxTi (CH3) 4, bisacetylacetonatocopper Cu
(CsH70□)2, bisdipivaloylmetaf"-ite copper C11 (C1lH190□)2, bishexafluoroacetylacetonatocopper Cu (C5HF60□)2, etc.
A suitable combination of gases containing u atoms is introduced to create a mixed gas atmosphere, for example, A℃-Si, AρTi, Ar2-C.
Electrodes may be formed by selectively depositing a conductive material such as u, Ar2-3i-Ti, Ar2SL-Cu, or the like.

In addition, after forming a metal film mainly composed of A℃ or Ar2 with excellent crystallinity using the Afi-CVD method, or after forming a P-type semiconductor layer by diffusing Aρ after film formation, electrodes and wiring are formed. It's okay.

In this deposition step, a non-selective film forming method is applied to form the selectively deposited Ar1 film and the 5i0 insulating film.
By forming a metal film containing A° C. or A° C. as a main component also on the substrate 2, etc., it is possible to obtain a suitable metal film with high versatility as an electrode and wiring of a semiconductor device. Specifically, the metal film used as such an electrode and wiring is as follows.

Selectively deposited Afi, Ar2-3i, Aρ-Ti, A4
2-Cu, Ar2-8i-Ti Ar2-3i-C
A℃, Ar2-3i, Ar deposited non-selectively with u etc.
2-Ti, An-Cu, Ar2-3i-Ti, Ar2-
For example, a combination with 3i-Cu. The film forming method for non-selective deposition is CVD other than the above-mentioned A℃-CVD method.
method, sputtering method, etc. In this way, move the inside of the hole to
By using a two-step process of filling the contact hole with a metal with excellent crystallinity using the °C-CVD method and forming wiring using a non-selective film formation method, a void called a cavity is formed within the contact hole. Electrodes and wiring can be formed without any process.

[Experimental Example 1] Below, in order to demonstrate the superiority of the above A℃-CVD method and how high-quality the A℃ film deposited within the openings is, the present inventor previously demonstrated the The results of an example experiment conducted using the experimental device are shown.

As a substrate, a sample was prepared in which a 5in2 film with a thickness of 8000 mm was formed on an N-type single crystal Si wafer by thermal oxidation. This is made by patterning SjO□ with openings of various diameters ranging from 0.25 μm x 0.25 μm square to 100 μm x 1100 μm square to expose the underlying Si single crystal.

FIG. 4(A) is a schematic diagram showing a portion of this base.

Here, 401 is a single crystal silicon substrate as a conductive (electron-donating) substrate, and 402 is a thermally oxidized silicon film as an insulating film (non-electron-donating film). This is sample 1-1
shall be. 403 and 404 are openings (exposed parts),
Each has a different caliber.

First, a base provided with an insulating film having such an opening was placed in the load lock chamber 311. Hydrogen was introduced into the load lock chamber 3]1 as a reaction gas to create a hydrogen gas atmosphere. Next, the inside of the reaction chamber 312 was evacuated to approximately 1XIO-'Torr through the exhaust system 316b.

Then, the base body was moved and placed on the claw 331.

DMAH was supplied as a source gas from a gas line 319. N2 was used as the carrier gas for the DMAH line.

The second gas line 319' is for N2 as a reaction gas, and the carrier gas H2 is flowed from this second gas line 319', and the opening degree of a slow leak valve (not shown) is adjusted to control the inside of the reaction chamber 312. The pressure was approximately 1.5 Torr. DMAH was introduced into the reaction tube from the DMAH line.

The total pressure was approximately 1.5 Torr, and the DMAH partial pressure was approximately 5.0XIO-3 Torr. Thereafter, electricity was applied to the halogen lamp 330 to directly heat the wafer. In this way, as shown in FIG. 4(B), the A.degree.
05 was deposited.

The temperature of the substrate surface at this time was 270°C.

After the above Aj2 deposition is completed, the supply of DMAH is stopped, and the CV
D reaction chamber 312 is 5X using exhaust system 31f13b
It was evacuated until a degree of vacuum of 10-3 T'o r r or less was reached. After the load lock chamber 313 was evacuated to 5×1° Torr or less, the gate valve 310c was opened and the substrate was moved. After closing the gate valve 310c, N2 gas was flowed into the load lock chamber 313 until it reached atmospheric pressure, and the gate valve 310d was opened to take out the substrate from the apparatus.

Next, using the same base as previously prepared,
This time, the substrate surface temperature was increased from 200℃ to 490℃ by direct heating.
The Aj2 film was formed.

All other film forming conditions were the same here.

The results are shown in Table 1.

As can be seen from Table 1, direct heating increases the substrate surface temperature by 2.
In the temperature range above 60°C, Afi was selectively deposited within the open pores at a deposition rate of 3000-5000 people/min.

When we investigated the characteristics of the ρ film inside the openings when the substrate surface temperature was in the range of 260 to 440'C, we found that it contained no carbon, had a resistivity of 2.8 to 3.4 μΩcm, and a reflectance of 90 to 95%. ,1
It was found that the hillock density of 0 to 10 μm or more was good, with almost no spike occurrence (probability of failure of a 0.15 μm junction).

On the other hand, when the substrate surface temperature was 200° C. to 250° C., the deposition rate was low at 1000 to 1500 sheets/min, and the throughput was also low to 7 to 10 sheets/h. Also, if the substrate surface temperature exceeds 440°C, the reflectance will be 60% or less, 1μ
When the hillock density of m or more is lO~io'cm-, the occurrence of spikes is 0 to 30%, and the characteristics of the A and C films in the opening are reduced [Experimental Example 2] Next, by the method described above, as described below. An An film was formed on a substrate (sample) having the following configuration.

A silicon oxide film as a second substrate surface material is formed by CVD on the single crystal silicon as the first substrate surface material, and buttering is performed by a photolithography process to partially cover the single crystal silicon surface. was discharged.

At this time, the thickness of the thermally oxidized 5in2 film was 7000 mm, and the exposed area of single crystal silicon, that is, the size of the opening, was 0.25 μm.
It was 0.25 μm to 100 μm×100 μm. Sample 1-2 was prepared in this way. (Hereinafter, such a sample will be referred to as "CVD Sin, (hereinafter abbreviated as SiO□)/single crystal silicon").

Sample 1-3 is a poron-doped oxide film/single crystal silicon formed by atmospheric pressure CVD, Sample 1-4 is a phosphorus-doped oxide film/single crystal silicon formed by atmospheric pressure CVD, and sample 1-5 is formed by normal pressure CVD. Sample 1-6 is a nitride film/single crystal silicon deposited by plasma CVD, Sample 1-7 is a thermal nitride film/single crystal silicon film, Sample 1-8 is a nitride film/single crystal silicon film deposited by plasma CVD. Sample 1-9 is a nitride film/single crystal silicon film formed by low pressure DCVD, and Sample 1-9 is a nitride film/single crystal silicon film formed by an ECR device.
It is single crystal silicon.

For all the samples described above, single crystal Afl films could be formed with good selectivity and good reproducibility.

Furthermore, samples 1-11 to 1-179 (Caution: Sample number 1-
10.20.30.40.50.6o, 70.80.9
0.100.110.120.130,140,150
．． 160.170 are missing numbers). Single crystal silicon (single crystal Si), polycrystalline silicon (polycrystalline Si), amorphous silicon (amorphous Si) as the first substrate surface material
, tungsten (W), molybdenum (Mo), tantalum (Ta), tungsten silicide (WSi), titanium silicide (TiSi), aluminum (A°C), aluminum silicon (A°C-3i), titanium aluminum (Ar1-Ti) , titanium nitride (Ti-N),
Copper (Cu), aluminum silicon copper (Aj2-3i-
Cu), aluminum palladium (A° C.-Pd), titanium (Ti), molybdenum silicide (Mo-8i), and tantalum silicide (Ta-8i) were used. Second substrate surface material Toshiteha T-8i 02, S i O2
,BSG.

PSG, BPSG, P-8iN, T-3iNLP-3i
N, ECR-3iN. All the samples mentioned above also have good Aρ comparable to sample 1-1 mentioned above.
A film could be formed.

As explained above, the Aj2-CVD method is not only suitably applicable to the process of forming a P-type layer on any semiconductor substrate, but also suitably used for forming electrodes and wiring.

[Example 1] A substrate provided with an insulating film having an opening was prepared, DMAH was used as the raw material gas, hydrogen was used as the reaction gas, the substrate surface was maintained at 270°C, and the same Aρ as in the experimental example was prepared.
- 600 A° C. single crystals were formed in the openings by the CVD method. After that, heat treatment was performed at 900℃ for Aρ diffusion.
A mold diffusion layer was formed. Further, an electrode 6j2 was formed thereon. Since the diffusion coefficient in Si is an order of magnitude higher than that of conventional boron, it was possible to form a deep P-type diffusion layer at low temperatures and in a short time. Furthermore, there were almost no spikes in the opening, and a good P-type diffusion layer could be obtained.

[Example 2] This example is a MOSFET as an insulated gate transistor.
It is applied to the manufacturing method of

A semiconductor substrate having an insulating layer with an opening in a portion where a MOSFET was to be formed was prepared.

P in which Aρ was diffused using the same film formation method as in Example 1
A mold diffusion layer was formed. Next, the insulating coating layer and the Al2 remaining after diffusion were removed by a well-known wet etching method. Next, a gate insulating film 5 is formed by a well-known process.
03, gate electrode 504, source 505, drain 50
6. After forming the interlayer insulating film 507, a contact hole is formed, and DMAH and Si are formed using the Al2-CVD method.
Al2-3L by thermal CVD method using H4 and hydrogen
Source 508 and drain 510 electrodes having substantially horizontal surfaces were formed. Thereafter, an Al2-3i-Cu film was non-selectively deposited and patterned by sputtering to form wiring, thereby producing a MOSFET as shown in FIG. In this way, when the method of the present invention is used to form the Pwell of a MOSFET, a good P-type diffusion layer can be obtained as in Example 1, and the gate oxide film becomes a mixture of SiO2 and Aρ203, unlike the conventional method. We were able to form a gate oxide film with a higher dielectric constant than that of the previous oxide film. The contact holes of the source and drain electrodes were filled with Aβ-Si having excellent crystallinity, and there were no cavities. Also, Al2-CV
Due to the good surface properties of the Aρ-Si film inside the openings formed by the D method, Al2-Si selectively deposited inside the openings.
The film and the Ac31-Cu film made by sputtering are as follows:
The contact state was highly durable both electrically and mechanically.

(Example 3) This example is applied to a method for manufacturing a bipolar transistor.

First, boron (B) is implanted into silicon using a conventional ion implantation method to form a P+ buried layer 601.
was formed. Next, single crystal silicon was grown by epitaxial growth to form an insulating coating layer, and then an opening was formed in the region where the collector was to be formed. Seven hundred single crystals Aj2 were deposited by the same Aβ-CVD method as in Experimental Example 1, and heat treated at 900° C. for A° C. diffusion to form a P-collector 602 layer. Thereafter, a base region 603 was formed by ion-implanting phosphorus (P). Next, Aβ was deposited again under An-CVD film forming conditions and heat treated for diffusion at A° C. to form an emitter region 604. Thereafter, an A°C-8L film was formed to serve as the base, emitter, and collector electrodes by the 8-CVD method using DMAH, SiH4, and hydrogen. Thereafter, a conventional sputtering method is used to non-selectively deposit and pattern an Aρ-8i-Cu film to form a wiring 605 to create a bipolar transistor as shown in FIG. did. The P-type semiconductor layer formed in this example was also good as in Examples 1 and 2, and the contact between the electrode and the electrode and the wiring was also as good as in Example 2. In this example, since Al2 is used as the P-type semiconductor impurity, a deep P-type diffusion layer can be formed in a shorter time than when using conventional boron as the P-type impurity. .

Note that the present invention is not limited to these embodiments, but any configuration that achieves the object of the present invention may be used.

[Effects of the Invention] (1) By using octaβ as a P-type semiconductor impurity, a deeper P-type diffusion layer can be formed at a lower temperature and in a shorter time than before.

(2) By diffusing /M2 atoms from the single crystal Aρ to the semiconductor layer, which has a good interface with Si, a good P-type diffusion layer with almost no alloy spikes etc. can be obtained.

(2) The CVD method using alkyl aluminum hydride and hydrogen makes it possible to selectively grow Afi only on a desired semiconductor, eliminating the need for patterning and simplifying the process.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a P-type semiconductor layer formed according to the present invention, FIG. 2 is a process diagram for forming a P-type semiconductor layer according to the present invention, FIG. 3 is a diagram of ε to a single crystal according to the present invention, and FIG. Fig. 5 is a schematic cross-sectional view of a MOSFET with a P-type well according to the present invention, Fig. 6 is a schematic cross-sectional view of a bipolar transistor having a P-type buried layer, collector layer, and emitter layer according to the present invention, and Fig. 7 is a schematic cross-sectional view of a MOSFET with a P-type well according to the present invention. FIG. 101.201,401,501,701...Substrate, 102.202,402...Insulating film (non-electron donating film), 103.203,405...4 deposited film, 104.2
04,502,705...P-type semiconductor region, 205...electrode, 310a-310d...mechanical gate valve, 311.313...load-lock chamber, 316a-31
6c... Exhaust means, 3]8... Substrate support, 319... Raw material gas introduction line, 319゛... Reaction gas introduction line, 319-1...
- Bubbler 330... lamp, 331... claw for holding the substrate, 401... conductive (electron donating) substrate, 403.40
4,703... Opening portion, 503... Gate insulating film, 504... Gelt electrode, 505... Source region, 506... Drain region, 507... Interlayer insulating film, 508... -Source electrode, 509...Drain electrode, 510.605...Wiring, 601...P1 buried layer, 602...P-implemented layer 603...Base region 604...Emitter region 702. ...Silicon oxide layer 704...Polycrystalline Afi film

Claims (2)

[Claims] (1) In a method of manufacturing a semiconductor device having a P-type conductivity type semiconductor region, a single-crystal aluminum layer is formed on the main surface of a semiconductor substrate, and aluminum is diffused into the semiconductor substrate to form the P-type conductivity type semiconductor. A method of manufacturing a semiconductor device, comprising forming a region. (2) In a method for manufacturing a semiconductor device having a P-type conductivity type semiconductor region, aluminum is deposited on the main surface of a semiconductor substrate by a CVD method using an alkyl aluminum hydride gas and hydrogen; A method of manufacturing a semiconductor device, comprising forming the P-type conductivity type semiconductor region by diffusing aluminum.