JPS62153194A - Method for molecular beam epitaxial growth - Google Patents

Abstract

PURPOSE:In crystal growth on a semiconductor substrate containing Al, to make it possible to grow good crystal on an exposed face after removal of surface oxidized film, by removing the surface oxidized film by hitting molecular beam of Mg and/or Be to the film. CONSTITUTION:An Al-containing semiconductor substrate 1, for example, is obtained by laminating an AlGaAs layer 1b to GaAs crystal 1a and a surface oxidized film 1c is formed on the layer since the layer is exposed to atmosphere once. In a degassing process to remove the surface oxidized film 1c, the substrate 1 is heated by sending an electric current to a heater 11, then a Mg shutter 2a is opened and Mg beam is hit to the surface of the substrate 1. The surface oxidized film 1c is reduced and clean AlGaAs crystal face is exposed. Then, good crystal can be grown on the exposed crystal face in the following process.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a molecular beam epitaxy growth method for growing crystals on a semiconductor substrate containing AQ.

(Prior art and its problems) AQ Semiconductor crystals containing AQ, such as GaAs, are easily oxidized on the surface, so it is relatively difficult to grow on them after leaving them in the atmosphere0. , Japanese Journal of Applied Physics (
In manufacturing a buried structure semiconductor laser as shown in Vol. 19, pages L591-L594 of JJAP), it is necessary to re-grow the AllGaAs layer in the second liquid phase growth. However, the second growth is AQGaAs
The reproducibility and yield were poor due to the oxide film. If molecular beam epitaxy is used instead of this liquid phase growth method, regrowth on AQGaAs is relatively easy. Growing crystals was difficult.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a molecular beam epitaxy growth method that eliminates the above-mentioned drawbacks and can grow good crystals on a semiconductor substrate containing AQ.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides means for removing oxides on the surface of a semiconductor substrate containing Al and a degassing process on the semiconductor substrate. A molecular beam epitaxy growth method includes a step of irradiating a growing crystal component with a molecular beam.
The method is characterized by including a step of applying a molecular beam of at least one of e.

(Example) Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic diagram of a molecular beam epitaxy apparatus used in an embodiment of the present invention. The substrate 1 used is formed by laminating an Al1GaAs layer 1b on a GaAs crystal 1a, and a surface oxide film IC is formed thereon because it has been exposed to the atmosphere once. In a degassing step for removing the surface oxide film IC, the substrate 1 is heated by energizing the heater 11. Next, the Mg shutter 28 is opened and the Mg beam is applied to the surface of the substrate 1. Since AQ is more easily oxidized than AQ, the surface oxide film IC is reduced. In this way, in this embodiment, M
g reduces and removes the surface oxide film IC, resulting in a clean AQ
GaAs crystal planes are exposed. Therefore, a good crystal can be grown on the exposed crystal face in subsequent steps.

In this embodiment, Mg was used to reduce the surface oxide film, but in the present invention, Be may be used instead of Mg.

Further, in this example, the present invention was applied to growth on AllGaAs crystal, but the present invention is not limited to this, and may be applied to growth on InGaAQAs, I
nGaAQP.

It is clear that the present invention is also applicable to growth on crystals of other materials such as GaA (lsb).

(Effects of the Invention) To summarize, the advantages and effects of the present invention are that in crystal growth on a semiconductor substrate containing AQ, a surface oxide film can be easily removed, and a good crystal can be grown on the exposed surface after removal. It's about what you can do.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a growth apparatus used in one embodiment of the present invention. In the figure, 1 is a substrate, 1a is a GaAs crystal, and 1b is an AQGa crystal.
As layer, 1c is a surface oxide film, 2 is an Mg molecular beam source, 2a is an Mg shutter, 3 is a Be partial line source 3a is a Be shutter, 4 is a Ga partial line source 4a is a Ga shutter, 5 is an AQ Molecular beam source, 5a is AfL shutter, 6 is As partial beam source 6a is As shutter, 17 is Si molecular beam source, 7
a is a Si shutter, 10 is a chamber, and 11 is a heater.

Claims (1)

[Claims] In a molecular beam epitaxy growth method including a degassing step of removing oxides on the surface of a semiconductor substrate containing Al and a step of irradiating the semiconductor substrate with a molecular beam of a growing crystal component, the degassing step includes the step of Mg and Be on the semiconductor substrate
A molecular beam epitaxy growth method comprising the step of applying a molecular beam of at least one of the above.