JP3097231B2 - Method for growing semiconductor thin film of InGaAs or InGaAsP - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of irradiating light on a substrate during the growth of a semiconductor thin film to suppress a thin film growth reaction. The present invention relates to a method for forming a semiconductor thin film.

[0002]

2. Description of the Related Art As semiconductor devices for optoelectronics and the like become more sophisticated and more sophisticated, the manufacturing process thereof is becoming more and more complicated. In order to simplify the process, not only a proposal for an element structure but also a proposal for a semiconductor thin film manufacturing process have been made. For example, Japanese Journal of Applied Physics (Japanese J
ournal of Applied Physics) Vol. 30 No. 1A (1991)
As shown on page 14, when forming a semiconductor thin film,
2. Description of the Related Art A technique has been developed in which a semiconductor substrate in a metalorganic molecular beam epitaxy (MOMBE) apparatus is partially irradiated with light to selectively suppress the growth rate or control the composition of a semiconductor thin film on the semiconductor substrate. When a thin film having a different thickness or a different composition is selectively formed by this thin film growth method, physical properties such as optical characteristics of a portion irradiated with light, for example, photoluminescence (PL) intensity do not irradiate light. There was a drawback that it deteriorated compared to the part.

[0003]

SUMMARY OF THE INVENTION The present invention has been proposed to improve the above-mentioned drawbacks, and its object is to selectively grow or control the composition of a semiconductor thin film while irradiating a semiconductor substrate with light. Another object of the present invention is to improve the physical properties of a crystal whose growth is controlled or whose composition is partially controlled by irradiating light.

[0004]

In order to achieve the above-mentioned object, the present invention uses a metalorganic molecular beam epitaxy method to irradiate a part of the substrate with a laser beam while irradiating a part of the substrate with a III-V light source. When growing a Group InGaAs or InGaAsP semiconductor thin film, the supply amount of the Group V metal is adjusted to a supply amount that gives a low constant value of the ratio between the growth rate of the light irradiation part and the growth rate of the light non-irradiation part. The InGaAs or the InGaAs or the InGaAs or the InGaAs or the InGaAs.
The gist of the present invention is a method of growing a semiconductor thin film of InGaAsP . Further, the present invention uses a metalorganic molecular beam epitaxy method, and irradiates a part of the substrate with laser light while irradiating a group III-V InGaAs or
When growing the InGaAsP semiconductor thin film, the irradiation intensity of the laser beam per unit time is set to a constant value where the ratio of the growth rate of the light irradiation part to the growth rate of the light non-irradiation part is a low constant value and a high constant value. Giving laser intensity and
InGaAs or InGaAs characterized in that the ratio of the growth rates is raised and lowered across a region of laser intensity where the ratio rapidly changes.
The gist of the present invention is a method for growing a semiconductor thin film of InGaAsP . Further, the present invention uses a metalorganic molecular beam epitaxy method to irradiate a part of the substrate with a laser beam while irradiating a part of the substrate with a group III-V InGaAs or IGaAs.
nGaAsP semiconductor thin film growing method When growing a semiconductor thin film, the substrate temperature is set at a constant value where the ratio between the growth rate of the light-irradiated part and the growth rate of the light non-irradiated part is low, and the substrate temperature is a high constant value. A temperature of the semiconductor thin film of InGaAs or InGaAsP, wherein the temperature is raised and lowered over a region of the substrate temperature where the ratio of the growth rate changes rapidly.
The gist of the invention is a film growth method . Further, the present invention uses a metalorganic molecular beam epitaxy method to irradiate a part of the substrate with a laser beam while irradiating a part on the single crystal substrate with III.
When growing a group V InGaAs or InGaAsP semiconductor thin film, the supply amount of the group III raw material includes a ratio of the growth rate of the light irradiation part to the growth rate of the light non-irradiation part including zero which gives a high constant value. The supply amount and the supply amount giving a low constant value are increased or decreased over the region of the supply amount of the group III raw material in which the ratio of the growth rates changes abruptly. InGaAs or InGaAsP semiconductor thin film characterized by irradiating light
The gist of the invention is a growth method .

[0005]

According to the present invention, there is provided a method for growing a semiconductor thin film on a single crystal substrate while irradiating light by using a metalorganic molecular beam epitaxy method. By continuously and repeatedly performing growth under conditions not performed, it is possible to improve the physical properties of a crystal whose growth is partially controlled or whose composition is controlled by irradiating light.

[0006]

Next, an embodiment of the present invention will be described. The embodiment is merely an example, and it goes without saying that various changes or improvements can be made without departing from the spirit of the present invention. The present invention relates to an InGaAs film or InGa
In the growth of an AsP film, under a growth condition in which the growth rate of the film is constant or decreases with an increase in the substrate temperature,
By irradiating a part of the substrate surface with light to partially increase the substrate temperature, the growth rate of the light-irradiated portion, the Ga composition, and in the case of a quaternary system, both the P composition decrease as compared with the non-irradiated portion. It depends on what you find.

FIG. 1 shows the dependence of the ratio of the growth rate of the portion irradiated with the laser beam to that of the portion not irradiated with the laser beam during the growth of the InGaAs (P) film on the V group supply amount. That is, while maintaining the substrate at a predetermined temperature and irradiating the substrate with a laser beam of a predetermined intensity and increasing the supply amount of group V, the ratio of the growth rates of the portion irradiated with the laser beam and the portion not irradiated with the laser beam suddenly becomes 0.5 From 1 to That is, it is understood that the suppression of the growth does not occur. At this time, the physical property value is not good in the portion where the growth is suppressed, and is inferior to the portion where the growth is not suppressed. Therefore, by changing the supply amount of the group V between a value at which growth is suppressed and a value at which growth is not suppressed, for example, between 3 sccm and 7 sccm, growth is suppressed and the physical property value is excellent. A membrane can be obtained.

FIG. 2 shows the dependence of the ratio of the growth rate of the portion irradiated with the laser beam to the portion not irradiated with the laser beam during the growth of the InGaAs (P) film on the intensity of the laser beam per unit time. That is, when the intensity of laser light per unit time is increased while the substrate is kept at a predetermined temperature and a predetermined amount of Group V metal is supplied, the ratio of the growth rates of the portion irradiated with the laser beam and the portion not irradiated with the laser beam sharply increases. To 0.5. That is, it is understood that the growth is suppressed. At this time, the physical property value is not good in the portion where the growth is suppressed, and is inferior to the portion where the growth is not suppressed. Therefore,
The growth is suppressed by switching the laser beam intensity per unit time between a value at which growth is not suppressed and a value at which growth is suppressed, for example, between 100 W / cm ² and 200 W / cm ^2. In addition, a film having good physical properties can be obtained. The method of increasing or decreasing the laser light intensity per unit time includes the method of increasing or decreasing the laser light intensity itself, the method of changing the laser light intensity constant, turning it on and off in a short time and changing the interval, and the laser Are scanned, and the speed is changed to increase or decrease as a time average, or a combination thereof.

FIG. 3 shows the dependence of the ratio of the growth rate of the portion irradiated with the laser beam to the portion not irradiated with the laser beam during the growth of the InGaAs (P) film on the substrate temperature. When a predetermined amount of group V metal is supplied to the substrate and the substrate temperature is increased while irradiating a laser beam of a predetermined intensity, the ratio of the growth rates of the portion irradiated with the laser beam and the portion not irradiated with the laser beam suddenly increases from 1 to 1. 0.5. That is, it is understood that the growth is suppressed. At this time, the physical property value is not good in the portion where the growth is suppressed, and is inferior to the portion where the growth is not suppressed. Therefore, by moving the substrate temperature between a value at which growth is suppressed and a value at which growth is not suppressed, for example, by moving the substrate temperature between 500 ° C. and 520 ° C.,
Growth can be suppressed and a film having good physical properties can be obtained.

FIG. 4 shows the dependency of the ratio of the growth rate of the portion irradiated with the laser beam to the portion not irradiated with the laser beam when the InGaAs (P) film is grown upon the group III supply amount. The group III supply amount is represented by the total supply amount of gallium and indium organometallic raw materials, for example, triethylgallium and trimethylindium. When the supply amount of the group III is increased, the ratio of the growth rates of the portion irradiated with the laser beam and the portion not irradiated with the laser beam sharply becomes 1 to 0.5. That is, it is understood that the growth is suppressed. At this time, the property value is not good in the portion where the growth is suppressed, and is inferior to the property value in the portion where the growth is not suppressed. Therefore, by changing the supply amount of the group III between a value at which growth is suppressed and a value at which growth is not suppressed, for example, between 0.1 sccm and 1.0 sccm, growth is suppressed and physical properties are suppressed. A film having a good value can be obtained.
By stopping the supply of the group III raw material, V
By supplying only the group material, the physical properties of the thin film can be improved. Although the above description of FIGS. 1 to 4 is for the bulk, the multiple quantum well structure (M
The same applies to QW) and single quantum well structure (SQW). Next, a specific example will be described.

(Example 1) Using an organometallic molecular beam epitaxy apparatus, 0.4 W argon laser light (514.
InGaAs was grown at a substrate temperature of 520 ° C. while irradiating 5 nm) to a diameter of 400 μm. Triethyl gallium and trimethyl indium were used as group III raw materials. 3 sccm and 7 sc every 10 seconds
cm. As a result, a thin film was obtained in which the growth rate of the light-irradiated portion was 90% of that of the non-light-irradiated portion, and the photoluminescence intensity was equal between the light-irradiated portion and the non-light-irradiated portion.

(Example 2) Using an organometallic molecular beam epitaxy apparatus, the supply amount of arsine was set to 3 sccm,
While irradiating an argon laser beam (514.5 nm) with a diameter of 400 μm, the substrate temperature was InGaAs at a substrate temperature of 520 ° C.
/ InP-MQW was grown. Triethyl gallium and trimethyl indium were used as group III raw materials. An argon laser beam intensity was applied during the growth of InGaAs for 20 seconds, and was changed from 2 W to 1 W to 1 W to 2 W. As a result, a thin film having the same photoluminescence intensity in the light-irradiated portion and the non-light-irradiated portion and having a peak wavelength different by 150 nm was obtained.

(Example 3) Using an organometallic molecular beam epitaxy apparatus, the supply amount of arsine was set to 3 sccm,
0.4 W argon laser light (514.5 nm)
While irradiating with a diameter of 00 μm,
nGaAsP was grown. Triethyl gallium and trimethyl indium were used as group III raw materials. The argon laser light was turned on for 1 second and turned off for 2 seconds using a chopper. As a result, the growth rate of the light-irradiated portion is 95% of that of the non-light-irradiated portion.
%, A thin film having the same photoluminescence intensity in the light-irradiated part and the light-non-irradiated part was obtained.

(Embodiment 4) Using an organometallic molecular beam epitaxy apparatus, the supply amount of arsine was set to 3 sccm,
0.4 W argon laser light (514.5 nm)
InGaAsP was grown while irradiating with a diameter of 00 μm. Triethyl gallium and trimethyl indium were used as group III raw materials. The substrate temperature was cycled between 500 ° C. and 520 ° C. every 10 seconds. As a result, a thin film was obtained in which the growth rate of the light-irradiated portion was 85% of that of the non-light-irradiated portion, and the photoluminescence intensity was the same between the light-irradiated portion and the non-light-irradiated portion.

(Example 5) Using an organometallic molecular beam epitaxy apparatus, 0.4 W argon laser light (514.
InGaAs was grown at a substrate temperature of 520 ° C. while irradiating 5 nm) to a diameter of 400 μm. Triethyl gallium and trimethyl indium were used as group III raw materials. The supply amount of the group III raw material is set to 0.1 sccm every 10 seconds.
And 1.0 sccm. As a result, a thin film was obtained in which the growth rate of the light-irradiated portion was 95% of that of the non-light-irradiated portion and the photoluminescence intensity was 80% of that of the light-irradiated portion. Further, the photoluminescence peak wavelength was shifted by 20 nm. In addition, arsine was used as a group V raw material.

(Example 6) Using an organometallic molecular beam epitaxy apparatus, 0.4 W of argon laser light (514.
InGaAs was grown at a substrate temperature of 520 ° C. while irradiating 5 nm) to a diameter of 400 μm. Triethyl gallium and trimethyl indium were used as group III raw materials. The supply of the Group III raw material was switched between 0 sccm and 0.8 sccm every 10 seconds. As a result, a thin film was obtained in which the growth rate of the light-irradiated portion was 90% of that of the non-light-irradiated portion, and the photoluminescence intensity was 90% of that of the light-irradiated portion. The photoluminescence peak wavelength is 1
It was shifted by 8 nm. In addition, arsine was used as a group V raw material.

(Example 7) Using an organometallic molecular beam epitaxy apparatus, 0.4 W argon laser light (514.
InGaAsP was grown at a substrate temperature of 520 ° C. while irradiating 5 nm) to a diameter of 400 μm. Triethyl gallium and trimethyl indium were used as group III raw materials. 0.1 scc every 10 seconds
and back and forth between m and 1.1 sccm. at the same time,
Laser irradiation was performed only at 1.1 sccm. As a result, a thin film was obtained in which the growth rate of the light-irradiated portion was 95% of that of the non-light-irradiated portion, and the photoluminescence intensity was the same between the light-irradiated portion and the non-light-irradiated portion. Further, the photoluminescence peak wavelength was shifted by 15 nm. Note that arsine and phosphine were used as group V raw materials.

(Example 8) Using an organometallic molecular beam epitaxy apparatus, 0.4 W argon laser light (514.
InGaAsP was grown at a substrate temperature of 520 ° C. while irradiating 5 nm) to a diameter of 400 μm. Triethyl gallium and trimethyl indium were used as group III raw materials. The supply amount of the group III raw material was switched between 0 sccm and 0.7 sccm every 10 seconds. At the same time, 0.7
Laser irradiation was performed only at the sccm. As a result, a thin film was obtained in which the growth rate of the light-irradiated portion was 90% of that of the non-light-irradiated portion, and the photoluminescence intensity was equal between the light-irradiated portion and the non-light-irradiated portion. The photoluminescence peak wavelength is 16 nm.
Was shifting. Note that arsine and phosphine were used as group V raw materials.

[0019]

As described above, by using the growth method of the present invention, a semiconductor thin film having a composition and thickness different from those of other places can be formed at a desired place on a substrate, and the physical properties of the thin film can be formed. The value can be good. Therefore, optical devices such as multi-wavelength lasers, which are expected as key devices in the future, and optical and electronic integrated circuits (OEIC)
Useful for the formation of

[Brief description of the drawings]

FIG. 1 shows the dependence of the ratio of the growth rate of a portion irradiated with laser light to a portion not irradiated with laser light when the InGaAs (P) film is grown during growth of an InGaAs (P) film, on the V group supply amount.

FIG. 2 shows the dependence of the ratio of the growth rate of the portion irradiated with the laser beam to the portion not irradiated with the laser beam when growing the InGaAs (P) film on the laser beam intensity per unit time.

FIG. 3 shows the dependence of the ratio of the growth rate of the portion irradiated with the laser beam to the portion not irradiated with the laser beam during the growth of the InGaAs (P) film on the substrate temperature.

FIG. 4 shows the dependence of the ratio of the growth rate of the portion irradiated with the laser beam to the portion not irradiated with the laser beam when the InGaAs (P) film is grown upon the group III supply amount.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-2-246110 (JP, A) JP-A-61-124122 (JP, A) JP-A-4-31391 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) H01L 21/203 C30B 23 / 08,29 / 40

Claims (4)

(57) [Claims] 1. The method according to claim 1, wherein a metalorganic molecular beam epitaxy method is used.
When growing a group III-V InGaAs or InGaAsP semiconductor thin film on a single crystal substrate while irradiating a part of the substrate with a laser beam, the supply amount of the group V metal is determined by the growth rate of the light irradiation part and the optical non-uniformity. The supply amount giving a low constant value and the supply amount giving a high constant value, the ratio of the growth rate of the irradiation unit,
InGaAs, wherein the ratio of the growth rate is increased or decreased over a region of the supply amount of the group V metal in which the ratio rapidly changes.
Or a method of growing a semiconductor thin film of InGaAsP . 2. Using an organometallic molecular beam epitaxy method,
When growing a group III-V InGaAs or InGaAsP semiconductor thin film on a single crystal substrate while irradiating a part of the substrate with laser light, the irradiation intensity of the laser light per unit time is determined by the growth rate of the light irradiation part. The laser intensity that gives a low constant value and the ratio of the growth rate of the light non-irradiated portion and the laser intensity that gives a high constant value are raised and lowered across the region of the laser intensity where the ratio of the growth rate changes abruptly. A half of InGaAs or InGaAsP.
Conductor thin film growth method . 3. Using an organometallic molecular beam epitaxy method,
When growing a group III-V InGaAs or InGaAsP semiconductor thin film on a single crystal substrate while irradiating a part of the substrate with laser light, the substrate temperature is controlled by the growth rate of the light irradiation part and the growth of the light non-irradiation part. InGaAs or a substrate characterized in that a substrate temperature giving a constant value with a low ratio of the speed and a substrate temperature giving a high constant value are raised and lowered over a region of the substrate temperature where the ratio of the growth rates changes rapidly. InGa
A method for growing a semiconductor thin film of AsP . 4. The method according to claim 1, wherein the metalorganic molecular beam epitaxy method is used.
When growing a group III-V InGaAs or InGaAsP semiconductor thin film on a single crystal substrate while irradiating a part of the substrate with laser light, the supply amount of the group III raw material is determined by the growth rate of the light irradiation part and the optical non-uniformity. The ratio between the growth rate of the irradiation part and the supply rate including zero to give a high constant value and the supply rate to give a low constant value are defined as the supply rate region of the group III raw material in which the growth rate ratio changes rapidly. A laser beam is radiated at a supply amount giving at least a low value, and a half of InGaAs or InGaAsP.
Conductor thin film growth method .