JP2679011B2 - Method of introducing impurity atoms - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to diamond, BN, SiC or organic materials used for semiconductors in the electronic industry.
In order to control the conductivity of electronic materials such as organic semiconductors ,
The present invention relates to a method of introducing an impurity element.

[0002]

2. Description of the Related Art In recent years, electronic materials such as diamond, BN, SiC and organic semiconductors obtained by a method such as a CVD method (chemical vapor deposition method) have been studied for use in semiconductors in the electronic industry, Is also attracting attention.

In order to widely use these materials, it is necessary to establish a technique for producing a material having good crystallinity and to control p-type or n-type conductivity in order to enhance the functionality. is there. The conventional method is:
For example, when a p-type or n-type crystal is manufactured, there is a method of mixing atoms serving as a dopant into a source gas or the like, but there are problems such as high manufacturing temperature and insufficient activation of the dopant. is there.

On the other hand, at present, it is widely used as a semiconductor material.
In silicon, which is used to accelerate impurity atom ions
Material production by ion implantation method that irradiates silicon with
A method of introducing post-impurity atoms is known. This way
If impurity atoms are introduced by
Defects are generated in the crystal due to the kinetic energy of
Therefore, a thermal annealing process is required to remove the defects.
I need it. However, the above materials, such as diamond,
Thermal annealing, which is usually done in the silicon process
In crystal processing, crystal defects cause graphitization etc.
Phase change occurs, it is difficult to remove defects
There are issues.

[0005]

As described above, with respect to electronic materials such as diamond, BN, SiC, and organic semiconductors , impurity atoms should be contained in a form in which conductivity is sufficiently controlled.
It was difficult to introduce. In particular, it was said that impurities could not be introduced after the material was manufactured .

Therefore, the present invention considers the problems of such conventional impurity introduction methods, and considers diamond, BN, and Si.
In order to enable conductivity control of C and organic semiconductors,
It is an object to provide a method capable of introducing an impurity atom after manufacturing a material .

[0007]

The method for introducing impurity atoms of the present invention is to irradiate diamond, BN, SiC or an organic semiconductor material with accelerated particles and then to expose them to an atmosphere containing hydrogen radicals or hydrogen ions. .

In the constitution of the present invention of the method for introducing impurity atoms, it is preferable that the accelerated particle state is an ion.

Further, in the constitution of the present invention of the method for introducing impurity atoms, the accelerated particles are B, Al, Ga, I.
A Group III element such as n or a Group V element such as N, P, As or Sb is preferable.

In the structure of the present invention of the method for introducing impurity atoms, the dose of accelerated particles is preferably 1 × 10 ¹⁸ or less per unit square cm. Even more preferred
Specifically, the number is 1 × 10 ¹⁶ or less per square cm .

Further, in the constitution of the present invention of the method for introducing impurity atoms, the temperature of the electronic material when irradiating the accelerated particles is preferably maintained at -200 ° C to 500 ° C.

In the structure of the present invention of the method for introducing impurity atoms, it is preferable that the atmosphere containing hydrogen radicals or hydrogen ions exposed after the accelerated particles are irradiated is in a plasma state.

Impurity atoms can be introduced into the material by accelerating the atoms serving as impurities to give energy and irradiating diamond, BN, SiC or an organic semiconductor material. This method is effective in that the controllability of the concentration and distribution of the element serving as the dopant is good, and the implantation region can be selected. However, as described above,
Defects are introduced into the crystal in the region irradiated with the child. So
As recovery method, as in the present invention, exposing to an atmosphere containing hydrogen radicals or hydrogen ions accelerated particles after irradiation (hereinafter, referred to as "hydrotreating") by, to remove the damage incurred during the irradiation, the particles Recrystallization of the implanted region
It becomes possible to promote .

As in the second aspect of the present invention, since the accelerated particles are in the state of ions, it is easy to control the energy and position of the particles to be irradiated.
It becomes possible to improve the controllability of the hydrogen treatment .

As in the third aspect of the present invention, the accelerated particles are group III elements such as B, Al, Ga and In, or N,
P, As, by Sb a V group element such as grain
This makes it easier to control the conductivity of the electronic material that has undergone child irradiation and hydrogen treatment .

As in the fourth aspect of the present invention, the dose of accelerated particles is 1 × 10 ¹⁸ or less per unit square cm, so that the electronic material is not damaged more than necessary.
In addition, the conductivity can be sufficiently controlled by hydrogen treatment.
Only a few impurity atoms can be introduced into the material .

As in the fifth aspect of the present invention, the temperature of the electronic material when the accelerated particles are irradiated is from -200 ° C to 5 ° C.
By keeping 00 ° C., since the state after the control and irradiated damage amount given to the electronic materials it is possible to control the particle
The controllability of hydrogen treatment after irradiation can be enhanced .

As in the sixth aspect of the present invention, since the atmosphere exposed to the irradiation of the accelerated particles is in a plasma state, the active hydrogen amount is large, so that the damage can be removed efficiently.
And the implantation region can be recrystallized .

[0019]

[Embodiment of the present invention will be described below with reference to the embodiment Nitsu <br/> There are drawings of the present invention.

(Embodiment 1) Nitrogen gas is used as a source gas, and the gas is turned into plasma.
The N-ion obtained by
Irradiated the yamonds. The energy of N ion is 100 keV,
The dose was 1 × 10 ¹⁶ pieces / cm ² . Of ion irradiation
As a result, N atoms have been introduced into the diamond.
Although confirmed by secondary ion mass spectrometry etc., many at the same time
It was found that the crystal defect of was generated.

FIG. 1 shows the situation. 1A is a Raman spectrum of diamond before ion irradiation, and FIG. 1B is a Raman spectrum of diamond after irradiation. It can be seen that the intensity of Raman scattering after irradiation shown in (b) is significantly reduced as compared with the intensity of (a). That is, it can be seen that the crystallinity was lowered by the ion irradiation and the ion damage was caused. Therefore,
An attempt was made to recover the damaged region by exposing the sample irradiated with ions to an atmosphere containing hydrogen radicals or hydrogen ions. FIG. 2 is a schematic view of an example of the apparatus used. The configuration will be described below.

This apparatus introduces microwaves from the outside of the vacuum chamber 302 to generate an atmosphere containing hydrogen radicals or hydrogen ions. Therefore, the vacuum chamber 302 is made of cylindrical quartz so that microwaves can enter the chamber. It uses a tube. The central portion of the E surface of the waveguide 306 through which the microwave generated by the microwave oscillator 305 propagates is the quartz tube 3
02 penetrates. A vacuum pump 303 for making the inside of the vacuum chamber 302 a vacuum and a gas inlet 304 for introducing gas are attached to the vacuum chamber 302. The damaged electronic material, which is the sample 301, is placed on a substrate table 307 in which a heater is incorporated so that it can be heated, and is also placed in a region where microwaves are incident.

Using such a device, the microwave oscillator 3
When the microwave is injected into the vacuum chamber 302 at 05, the sample 3
Plasma is generated in the area where 01 is installed. At that time, the pressure in the vacuum chamber 302 is usually preferably about 0.01 to 100 Torr. The temperature of electronic materials is mainly 600-900 ℃
Is preferably used. The gas introduced into the vacuum tank 302 may be a mixed gas, but generally has a purity of 99%.
The above hydrogen gas is preferable.

[0024] Oite specifically performed procedures in this embodiment is as follows.

First, a diamond irradiated with N ions was set as a sample 301 at a predetermined position in a vacuum chamber 302, and then the chamber was sufficiently evacuated by a vacuum pump 303. Then, hydrogen gas having a purity of 99.5% was introduced through the gas inlet 304, the pressure in the tank was kept constant at 30 Torr, and then microwave (200 W) was incident. In this way, the hydrogen gas subjected to microwaves becomes plasma containing active radicals and ions. Then, by exposing the sample to this plasma, the temperature of the electronic material became about 800 ° C. The time for exposing the sample to the plasma is 20 minutes. As a result, as shown in (c) of FIG. 1, by exposing the sample to this plasma, the Raman scattering intensity was restored to the Raman scattering intensity of diamond before ion irradiation. This means that the damage that the diamond suffered was removed and the crystallinity was restored by this treatment.
Similar results are obtained by electron energy loss spectroscopy (EELS)
The inventors have also confirmed the results in cathodoluminescence measurement (CL).

(Second Embodiment) As a result of performing the same experiment on other electronic materials (BN, SiC, organic semiconductor), particle irradiation and hydrogen treatment were performed.
The present inventors have confirmed that it is possible to introduce an impurity atom by

The particles to be accelerated are B, Al, Ga,
A group III element such as In or a group V element such as N, P, As and Sb can be used, but other particles may be used.

[0028]

[0029]

As is apparent from the above description,
According to the method of the present invention, diamonds of any atom not neat
Irradiation of materials such as Mondo, BN, SiC or organic semiconductor
And, by exposure to an atmosphere containing hydrogen radicals or hydrogen ions, to remove the damage incurred during the irradiation, irradiation
Since the recrystallization of the irradiated region is promoted, impurity atoms can be easily
Can be introduced into the material .

As in the second aspect of the present invention, since the accelerated particle state is an ion, it is easy to control the energy and position of the particle to be irradiated, so that the particle after irradiation can be easily controlled .
It becomes possible to improve the controllability of the hydrogen treatment .

As in the third aspect of the present invention, the accelerated particles are group III elements such as B, Al, Ga and In, or N,
P, As, by Sb a V group element such as grain
This makes it easier to control the conductivity of the electronic material that has undergone child irradiation and hydrogen treatment .

As in the fourth aspect of the present invention, the dose of accelerated particles is 1 × 10 ¹⁸ or less per unit square cm, so that the electronic material is not damaged more than necessary.
In addition, the conductivity can be sufficiently controlled by hydrogen treatment.
Only a few impurity atoms can be introduced into the material .

As in the fifth aspect of the present invention, the temperature of the electronic material when the accelerated particles are irradiated is from -200 ° C to 5 ° C.
By keeping 00 ° C., since the state after the control and irradiated damage amount given to the electronic materials it is possible to control the particle
The controllability of hydrogen treatment after irradiation can be enhanced .

As in the sixth aspect of the present invention, since the atmosphere exposed to the irradiation of the accelerated particles is in a plasma state, the active hydrogen amount is large, so that the damage can be removed efficiently.

[Brief description of the drawings]

Fig. 1 Before and after irradiation with 1 × 10 ¹⁶ / cm ² N ions
And llama of diamond after hydrogen plasma treatment
It is a graph which shows the result of electron spectroscopy.

FIG. 2 is a hydrogen plasma treatment used in one embodiment of the present invention .
It is a schematic diagram of a processing device.

[Explanation of symbols]

 301 Sample 302 Vacuum Tank 303 Vacuum Pump 304 Gas Inlet 305 Microwave Oscillator 306 Waveguide 307 Substrate Stand

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C30B 29/36 C30B 29/36 A 29/38 29/38 A 31/22 31/22 H01L 51 / 00 H01L 29/28 (72) Inventor Masahiro Exit 1006, Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. In-house (56) Reference JP-A-3-76168 (JP, A) JP-A-3-22526 (JP, A)

Claims (6)

(57) [Claims] 1. A method for introducing an impurity atom, which comprises irradiating a material of diamond, BN, SiC or an organic semiconductor with accelerated particles and then exposing the material to an atmosphere containing hydrogen radicals or hydrogen ions. 2. A method of introducing impurity atoms of claim 1, wherein the state of the accelerated particles are ions. 3. The accelerated particles are B, Al, Ga, In
Group III elements such as or V such as N, P, As, Sb
The method for introducing an impurity atom according to claim 1 , wherein the impurity element is a group element. 4. accelerated as the irradiation of the particles, a method of introducing impurity atoms of claim 1, wherein the unit is square cm per 1 × 10 ¹⁸ or less. 5. accelerated temperature of the material when the particle is irradiated with, a method of introducing impurity atoms of claim 1, wherein the keep from -200 ° C. to 500 ° C.. 6. atmosphere containing an accelerated hydrogen radicals or hydrogen ions exposing after being irradiated with the particles, a method of introducing impurity atoms according to claim 1, characterized in that it is a plasma-like.