JPS58131737A - Liquid phase epitaxial growing method - Google Patents

Abstract

PURPOSE:To obtain the smooth surface of a crystal layer by a method wherein, after the material located in the liquid reservoir on a slide member has been fused by heating up a supporting stand and the slide member, the through-hole type liquid reservoir is placed in a standstill state on a substrate, and a crystal layer is formed on the substrate. Then, the slide member is shifted, the bottomed liquid reservoir is brought into the stationary state, and the above is cooled, thereby enabling to form the crystal layer on the substrate. CONSTITUTION:An Hg1-xCdxTe material is placed in the liquid reservoir 13 and the bottomed liquid reservoir 15 on a liquid-phase epitaxial growing device, and in the state wherein a CdTe substrate 3 is buried in the concavity 2 of the supporting stand, said device is heated up by a heating furnace after the device has been introduced into the reaction tube located in a H2 gas atmosphere. When the material in the liquid reservoirs 13 and 15 has been fused, the liquid reservoir 13 is placed at a stationary state on the substrate by shifting the slide member in the direction as indicated by the arrow B, and a crystal layer of Hg1-xCdxTe is epitaxially grown. Then, the bottomed liquid reservoir 15 is placed at a standstill on the substrate by shifting the slide member in the direction B. Through these procedures, the dissipation of Hg of easy-to-evaporate ingredient in the epitaxial layer can be prevented by the liquid phase of Hg1-xCdxTe located in the bottomed liquid reservoir on the substrate, thereby enabling to obtain the smooth surface of the crystal layer.

Description

Detailed Description of the Invention Technical Field of the Invention The present invention is a background of liquid phase Evita technology using a sliding method. narrow mercury, cadmium,
Compound semiconductor crystals such as tellurium (Hgs-zcdxTe) are used.

By the way, in order to obtain such compound semiconductor crystals in a large area and in a thin layer form, which is convenient for forming photoelectric conversion elements, chilled cadmium oxide (CdTe), which is generally easy to obtain large crystals with a large area, is used. Hg1-xc+1 on the substrate
A 4T6 crystal layer is formed using a liquid phase epitaxial growth method.

(Q) Prior Art and Problems The conventional method of determining the A/a length of liquid phase epitaxy will be explained with reference to FIG. 1, starting with Kei.

As shown in the figure, a rectangular parallelepiped-shaped support made of carbon
Te A/ for forming an epitaxial V-shaped crystal in the recess 2 of
After embedding the substrate 8 of cadmium chloride (CdTe 2 ), a liquid reservoir 5 in the form of a through hole provided in a slide member 4 that slides on a support table is filled with a forming material.

Next, liquid phase 1 consisting of such a support base and slide member
After the epitaxial growth apparatus is inserted into a reaction tube in a mercury (Ha) gas atmosphere, the reaction tube is heated in a heating furnace.

Next, when the crystal layer forming material in the liquid reservoir of the slide member melts into a liquid phase, the sulfide member is moved in the direction of arrow A to leave the liquid reservoir still on the substrate. After that, the temperature of the heating furnace was lowered and Hg1-xc (11Te) was deposited on the substrate.
form an epitaxial crystal layer. After that, further move the slide member in the direction of arrow A to move the liquid reservoir to the left side of the substrate, then turn off the power to the heating furnace and place H on the substrate.
A crystal layer of g1-xcdxTe is formed. However, with this method, since Hg in the Hg1-xCdxTe crystal layer is a particularly easily evaporable component, it remains on the substrate even when the power is turned off and the heating furnace is left to cool. Since the carbon material of the slide member is porous, Hg evaporates from the Hgl-1cdz're crystal layer formed on the substrate through the pores, and the evaporation of Hg creates depressions on the surface of the grown crystal layer. This results in the disadvantage that an uneven shape is formed.

Such an uneven shape causes an inconvenience in that it reduces the manufacturing yield of devices such as infrared sensing devices, especially devices that utilize the surface of the crystal layer.

■ Purpose of the Invention The present invention has a method that eliminates the above-mentioned drawbacks and prevents the formation of depressions on the surface of the epitaxial crystal layer due to the evaporation of easily evaporable components such as Hg during the growth of epitaxial μ crystals, thereby creating a smooth surface. The object of the present invention is to provide a liquid phase epitaxial growth method using a sliding method that can be obtained.

(θ) Structure of the Invention In order to achieve the above object, the liquid phase epitaxial growth method of the present invention includes embedding a substrate in the recess of a support base provided with a recess in which the substrate is to be buried, and sliding the substrate over the recess. After filling the through-hole-shaped liquid reservoir of the movable sphoid member and the bottomed liquid reservoir adjacent to the liquid reservoir with the material for the crystal layer to be formed on one substrate, the supporting table and the slide member are After heating the materials in each of the liquid reservoirs to melt them into a liquid phase, the through-hole-shaped liquid reservoirs are left on the substrate to form a crystal layer on the substrate, and then the slide member is The method is characterized in that an epitaxial crystal layer is formed on the substrate by moving the substrate, leaving a bottomed liquid reservoir still on the substrate, and then allowing the heating furnace to cool.

(Embodiment of the invention) An embodiment of the invention will be described below in detail with reference to the drawings.

Figure Q@ is a plan view of a liquid phase epitaxial growth apparatus used in the method of the present invention, and Figure 2(a) is a sectional view taken along the line X-7.

As shown in the figure, a slide member 11 of a liquid phase epitaxial growth apparatus used in the method of the present invention has a liquid reservoir 18 in the form of a through hole for accommodating a liquid phase 12 of a crystal layer of Hg1-IO (14Te) to be formed on the substrate. In addition, adjacent to the liquid reservoir,
Hg having the same composition as the liquid phase 12 contained in the liquid reservoir 18
A bottomed liquid reservoir 1 containing a liquid phase 14 of 1-XCdXTe
5 is set. In addition, around the recess 2 in which the CdTe substrate 8 of the support stand 16 is installed, Hgt-XC is placed on the substrate.
(A groove 17 is provided so that the liquid phase of Hg1-xcdxTe can enter when the liquid reservoir 18 used to form the IXTe crystal layer is left still.

The Hgl-1CdxTe material is placed in the liquid reservoir 18 of such a liquid phase epitaxial growth apparatus, and the bottomed liquid reservoir 15 is
A material of Hgl-1Cd4Te having the same composition is housed in the chamber, and a CdTe substrate 8 is buried in the recess 2 of the support, and the apparatus is introduced into a reaction tube in an H8 gas atmosphere. Heat the device in a heating furnace.

When the material in the liquid reservoir 18.15 is melted, the slide member is moved in the direction of arrow B and the liquid reservoir 1 is placed on the substrate.
8 was allowed to stand still, the temperature of the heating furnace was lowered, and a crystal layer of HJKx-xc (1xTe) was deposited on the substrate using an Evitaki V-ya.
Make it grow. Thereafter, the slide member is further moved in the direction B to place the bottomed liquid reservoir 15 on the substrate. In this way, Hg1XCd in the bottomed liquid reservoir on the substrate mentioned above.
The liquid phase of XTθ prevents Hg, which is an easily evaporable component in the epitaxial layer, from escaping through the porous carbon material of the slide member, so that the surface of the epitaxial crystal layer formed is free from depressions. It becomes smooth.

(2) Effects of the Invention As described above, according to the method of the present invention, Hg, which is an easily evaporable component, does not evaporate from the epitaxial crystal layer during the epitaxial growth process. Therefore, an epitaxial crystal having a smooth surface without forming a depression is produced. The layers give rise to advantages. In addition, in the examples of the present invention, the easily evaporable component H
Although the epitaxial growth of a compound semiconductor crystal containing Hg has been described above, it goes without saying that the method of the present invention can also be applied to the liquid phase epitaxial growth of a compound semiconductor crystal containing easily evaporable components other than Hg.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an apparatus used in a conventional liquid phase epitaxial growth method, and FIG. 2 (1L) and 2@ are sectional views of an apparatus used in a liquid phase epitaxial growth method of the present invention. In the figure, 1.16 is a support base, 2 is a recess, and 8 is a CdTe
Is the board 4.11 compatible? id member, 5.18°15 is a liquid reservoir, 6.12.14 is Hgt 1Cd4Te material, 1
7 indicates a groove. +-9

Claims (1)

[Claims] A substrate is buried in the recess of a support base having a recess in which the substrate is to be buried, and a through-hole shaped liquid reservoir of a slide member that slides and moves on the substrate, and a bottomed liquid reservoir adjacent to the liquid reservoir. After filling the liquid reservoirs with materials for the crystal layer to be formed on the substrate, heating the support base and the slide member to melt the materials in the respective liquid reservoirs into a liquid phase. ,
After a liquid reservoir with a through hole is placed on the substrate and the entire crystal layer is formed on the substrate, the slide member is moved and a liquid reservoir with a bottom is placed on the substrate, and then the heating furnace is heated. A liquid phase epitaxial growth method characterized by forming an epitaxial crystal layer on a substrate by allowing it to cool.