JPS582293A - Liquid phase epitaxial growing apparatus - Google Patents

Abstract

PURPOSE:To smoothen the surface of an epitaxial crystal layer and to enhance the yield of an infrared ray detecting element by coating the surfaces of the quartz support table and the quartz sliding member of an epitaxial growing apparatus with carbon. CONSTITUTION:The quartz support table 3 of an epitaxial growing apparatus is put in a quartz reaction tube 11, and a quartz evaporator 15 filled with acetone 14 is connected to one end of the tube 11 with a quartz cap 12 in-between. The tube 11 is evacuated from the open end B of the cap 12 and heated with a heating furnace 16 to decompose acetone 14, thereby coating the surface of the table 3 with carbon. The surface of the quartz sliding member 6 is similarly coated with carbon. A substrate 1 is set in the recess 2 of the table 3, the liq. holder 5 of the member 6 is packed with Hg1-xCdxTe material 4, and the table 3 and the member 6 are put in a reaction tube in a gaseous hydrogen atmosphere and heated to melt the material 4. The member 6 is then moved in the direction of an arrow A to gently place the liq. phase in the holder 5 on the substrate 1, and by dropping the temp., a crystal layer is grown.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a liquid phase Ebitaki Vyaμ growth apparatus.

Te/I/A/cadmium mercury chloride (Hgl-xCdzTe) used as a material for infrared sensing elements is generally mercury (Hgl-xCdzTe).
Since Hg) is easily evaporated, a crystal layer of Hg1-xCdzTe is formed on a substrate of cadmium chloride (CdTe) by liquid phase growth.

A conventional liquid phase epitaxial growth apparatus for such a crystal layer of Hgl zcdzTθ grows 1kl from carbon as shown in FIG. A support plate 8 having a recess 2 in which a substrate l of dTθ is buried, and a liquid phase 4 of a material Hg1-xC (1xTe) formed on the substrate l by sliding and moving on the support plate 8. It consists of a slide member 6 made of carbon and having a liquid reservoir δ having a through hole.

Using such a liquid phase epitaxial growth apparatus, Hg
1-XcaX+r, crystal layer ca're on substrate 1 substrate 1
A tube of Hg1-10 (1zT@) was filled in the liquid reservoir of the sliding member.
After inserting the liquid-phase Ebitaki Vyaru growth apparatus including the support stand and slide member into a reaction tube in a hydrogen (H8) gas atmosphere, the reaction tube is heated in a heating furnace to generate the Hgl-2cax.
Melt the 're material. After that, the slide member is moved in the direction of arrow A, and the liquid phase in the liquid reservoir 5 is allowed to stand still on the CdTe substrate, and while the temperature of the heating furnace is lowered, the liquid phase is placed on the substrate.
Figs-1. A friend growing a crystal layer of αzT43.

However, in the case of using the above-mentioned liquid-phase Ebitaki Vyaru growth apparatus made of carbon, the surface of the carbon constituting the growth apparatus exhibits an uneven shape when observed under a microscope, and Hg1-xCdXTe117 ) This causes the inconvenience of liquid phase entering. Also, Hgl z on the board
When the slide member is moved in the direction of arrow A after forming a crystal layer of cdz're, Hg1 gCαxTe remaining on the substrate in the carbon material at the bottom of the slide member
The liquid phase enters the substrate, and as the slide member is moved, this liquid phase spreads over the substrate, resulting in the inconvenience of forming an uneven shape on the surface of the epitaxially grown layer. The epitaxially grown layer having such an uneven shape may cause problems in subsequent steps such as mask alignment, and the yield of the formed infrared sensing elements may decrease.

The object of the present invention is to provide a liquid-phase vitreous oil which eliminates the above-mentioned drawbacks.

To achieve this purpose, a liquid phase epitaxy growth apparatus consists of a support base in which a substrate is buried, and a liquid phase of the material of the crystal layer to be formed on the substrate is accommodated by moving over the support base. The present invention is a liquid-phase epitaxy vessel growth apparatus made of a sphide member having a liquid reservoir, characterized in that the apparatus is made of stone plate whose surface is coated with carbon.

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

FIG. 2 is a schematic diagram for explaining a method of applying a carbon coat to the surface of the epitaxial growth apparatus of the present invention.

First, a liquid phase epitaxial growth apparatus including the above-mentioned support stand and slide member is manufactured from quartz. The surface of the Evitaki Vyaμ growth device made of quartz was finished smooth and observed under a microscope, and it was found that it did not exhibit any uneven shape like the surface of the Evitaki Vyaru growth device made of 4 carbon material. It is smooth and smooth.

Thereafter, as shown in FIG. 2, for example, a support stand 8 of such an epitaxial growth apparatus is inserted into a quartz reaction tube 11, and a quartz cap IB is placed on the end of the reaction tube. On the other hand, a quartz evaporator 1 filled with acetone ((CH8), Co) 14 is connected to a pipe 18 connected to the cap.
Set up 6.

After doing this 1. The open end B of the cap is evacuated using a vacuum pump until the inside of the reaction tube reaches a vacuum level of about 10 s'rorr. Thereafter, the temperature of the heating furnace 16 is increased, and when the temperature of the heating furnace reaches 1000 tK, the temperature of the heating furnace is controlled to a constant value. When maintained in this manner for a predetermined period of time, the (CHs) sCo is thermally decomposed, resulting in fine particles of carbon (C) adhering to the surface of the support base 18 to a predetermined thickness. On the other hand, carbon is applied to the surface of the slide member made of quartz in exactly the same manner as described above. The reason why carbon is coated on quartz in this way is that in quartz it is Hg1-xc (1xTe
The material is very compatible with quartz, so when the solidified liquid phase of Hgx = This is because it will damage the

As mentioned above, the carbon obtained by thermally decomposing (OH3)gco is in the form of fine particles, and since this adheres to the epitaxial growth device made of smooth quartz, the surface of the device is smooth. The aforementioned Hgt-zodzTe
There is no possibility that the liquid phase of Hg1-xcdxTe that remains on the substrate after the Evitaki Vyaμ growth will also enter the lower end of the sulfide member. Since it can be removed by wiping it off, the surface of the epitaxially grown layer formed will also be smooth.

As described above, when the liquid phase epitaxy V-coat growth apparatus of the present invention is used, one surface of the epitaxial V-coat crystal layer formed is smooth. This has the advantage of improving the yield of the sensing element.

[Brief explanation of the drawing]

Figure 1 is a diagram showing a conventional liquid phase epitaxial growth apparatus.
FIG. 8 is a schematic diagram illustrating a method of applying a carbon coat to the liquid phase epitaxial growth apparatus of the present invention.

Claims (1)

[Scope of Claims] A liquid phase epitaxy system comprising a support base in which a substrate is buried, and a slide member that slides on the support base and has a liquid reservoir containing a liquid phase of a material for a crystal layer to be formed on the substrate. A liquid phase epitaxial growth apparatus in which the surface of the apparatus is coated with carbon so as to have a surface similar to that of quartz.