JPH06144989A - Liquid phase epitaxy growing method - Google Patents

Abstract

PURPOSE:To prevent the hindrance of growth reproducibility as there is the loss of raw materials at the time of transferring the raw materials from a glass container to a melt reservoir when a solute, dopant raw material, mixed crystal raw materials, etc., are weighed by using a glass container. CONSTITUTION:The solute, the dopant raw material and the mixed crystal raw materials 2 are put into a container-shaped solid solvent metal 1 and are weighted. These materials are supplied as they are into the melt reservoir 3 and are subjected to growth. Since a glass container, etc., are not used for weighing the solute, the dopant raw material and the mixed crystal raw materials 2, the sure transfer of the entire raw material to the melt reservoir is possible and the growth is executed with high reproducibility.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid phase epitaxial growth method for semiconductor crystals.

[0002]

2. Description of the Related Art As a conventional technique for growing a semiconductor crystal, there is a slide boat method which is one of liquid phase epitaxial growth methods (LPE) and is effective for multi-layer growth. As shown in FIG. 3, this is a base 5 holding a substrate 4,
A plurality of melt reservoirs 3 for accumulating the raw material melt 6 are slid on each other, and the raw material melt 6 is brought into contact with the substrate 4 for growth (“Electronic material series gallium arsenide” Maruzen p56.
reference).

By the way, in the above-mentioned slide boat method, a predetermined amount of solvent metal, semiconductor raw material which is a solute, dopant and mixed crystal raw material 2 are put into the same number of melt reservoirs as the number of growing layers to carry out growth. . At this time, the amount of solute has a great influence on the layer thickness, the amount of dopant has a great influence on the carrier concentration, and the mixed crystal raw material has a great influence on the mixed crystal ratio. Therefore, the growth layer thickness, carrier concentration,
In order to grow the mixed crystal ratio with good reproduction, solute, dopant,
It is required to weigh mixed crystal raw materials with high accuracy.

[0004]

Conventionally, as shown in FIG. 4, these weighings are performed by using separate glass containers 7 and the like, and the weighings are put into the melt reservoir 3 containing the solvent metal 1. Was. However, in such a method, the accuracy may be impaired because a part of the raw material adheres and remains in the glass container at the time of charging even if the weighing is accurately performed.

The present invention has been made under such a technical background, and an object thereof is to accurately weigh solutes, dopants, and mixed crystal raw materials and utilize them for growth without leakage. Another object of the present invention is to provide a liquid phase epitaxial growth method with high reproducibility of growth conditions.

[0006]

In order to achieve this object, the method of the present invention is a container-shaped solid solvent, at least one selected from a solute, a dopant raw material and a mixed crystal raw material, weighed, It is characterized in that they are directly added to the melt reservoir for growth.

[0007]

When the solute, the dopant raw material, and the mixed crystal raw material are weighed in this manner, the solid solvent is formed into a container, and the raw material is put into the container and weighed. In addition, it is possible to eliminate the raw material loss that is conventionally associated with the time of charging from the inside of the glass container to the melt reservoir. Therefore, all the raw materials can be reliably supplied for growth, and high growth reproducibility can be realized.

[0008]

EXAMPLES An example of the present invention will be described below.
FIG. 1 is an explanatory view showing the outline of the method of the present invention. First, the solid solvent metal 1 used for growth is formed in a container shape. Here, as shown in FIG. 2, the solid solvent 1 may have a concave portion 1a into which the solute, the dopant raw material, and the mixed crystal raw material 2 can be introduced, and the outer shape thereof may be any shape. Then, the outer surface is shaved and adjusted to a predetermined weight.

Next, the solid solvent is used as a weighing container, and the solute, the dopant raw material, and the mixed crystal raw material 2 are put into the recess 1a and weighed. After weighing the solute, the dopant raw material, and the mixed crystal raw material, the solid solvent and the solid solvent are put into the melt reservoir of the growth apparatus.

As described with reference to FIG. 3, the growth apparatus is a slide boat composed of a melt reservoir 3 having the same number of growing layers and a substrate 5 holding a substrate 4. For growth, the raw material is melted by raising the temperature to a predetermined temperature, and when the temperature is lowered to a certain temperature, the melt reservoir and the substrate are relatively slid to bring the substrate 4 and the raw material melt 6 into contact with each other, and further at a predetermined speed The temperature is lowered to grow an epitaxial layer on the substrate. Then, by performing such an operation for each melt reservoir, a multilayer epitaxial layer is formed on the substrate.

The AlGaAs layer is actually grown by performing weighing using the above-mentioned method of the present invention and the conventional glass container,
The obtained epitaxial layers were compared in thickness, carrier concentration and Al composition. The test conditions were as follows, and each growth was performed 10 times, and the average value and the deviation were obtained. The results are shown in Table 1. (Example) As a solvent, 30.00 g of container-shaped metal Ga was used.
Polycrystalline GaAs as a solute, Al as a mixed crystal raw material, and Zn as a dopant were added to each and weighed, and then put into the melt reservoir as they were for growth. (Comparative Example) A solute, a mixed crystal raw material, and a dopant were weighed using a glass container, and these were put into a melt reservoir together with the same amount of the solvent as in the Examples to grow.

[0012]

[Table 1]

As shown in the table, it was confirmed that the deviations of the examples were small and the reproducibility was superior to the comparative examples.

[0014]

As described above, according to the method of the present invention, a solute, a mixed crystal raw material, and a weighing container for a dopant are used as a solvent, and the solvent is put into the melt reservoir as it is. Therefore, it is possible to eliminate the loss at the time of charging into the melt reservoir. Therefore, it is possible to carry out growth with high reproducibility, and GaA, which is a light receiving element material for LEDs and lasers, is used.
s, AlGaAs, InP, InGaAs, InGaA
It is effective if it is used for growth of each layer such as sP.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a method of the present invention.

2A and 2B show a solid solvent for growing a semiconductor material of the present invention, wherein FIG. 2A is a side view and FIG. 2B is a plan view.

FIG. 3 shows a slide boat used for epitaxial growth, (A) is a plan view, (B) is a front view, and (C).
Is a side view.

FIG. 4 is an explanatory diagram showing a conventional method for weighing raw materials in epitaxial growth.

[Explanation of symbols]

 1 Solvent Metal 1a Recess 2 Solute, Dopant Raw Material, Mixed Crystal Raw Material 3 Melt Pool 4 Substrate 5 Substrate 6 Raw Material Melt 7 Glass Container

Claims (3)

[Claims] 1. A container-shaped solid solvent is charged with at least one selected from a solute, a dopant raw material and a mixed crystal raw material, weighed, and these are directly added to a melt reservoir for growth. Liquid phase epitaxial growth method. 2. A solid solvent for growing a semiconductor material, which is shaped like a container. 3. A method for weighing a raw material for semiconductor material growth, which comprises placing at least one selected from a solute, a dopant raw material, and a mixed crystal raw material in a container-shaped solid solvent, and weighing the raw material.