JPS59190295A - Method for growing zns single crystal film - Google Patents

Abstract

PURPOSE:To obtain a high-quality ZnS single crystal, by carrying out the molecular beam epitaxial growth on the (100) plane of the single crystal substrate at specific substrate temperature and rate of crystal growth using ZnS as the source. CONSTITUTION:Molecular beam epitaxial growth of ZnS on the (100) plane of a single crystal substrate made of GaP, GaAs or a material having nearly the same lattice constant, is carried out by using ZnS single crystal or polycrystal as the source, at a substrate temperature of 230-280 deg.C and a growth rate of 0.4-1mum/hr. A high-quality ZnS single crystal film can be obtained by this process, and a blue light-emitting element can be manufactured from the product. Since the technique to manufacture red and green light-emitting elements of GaP has already been estabilished, a monolithic device emitting three primary colors can be obtained by the use of GaP substrate. The use of the (100) plane of the substrate gives the cleavage angle of 90 deg., and facilitates the processing of chips.

Description

[Detailed description of the invention] (b) Utilization fields in the IL industry The present invention relates to a ZnS crystalline film growth method.

(Ij) Prior art Zn5 (zinc sulfide), which is one of the compounds, is regarded as one of the materials for obtaining blue light-emitting devices because of its large size. There is C.

However, it is difficult to obtain a high purity single crystal of ZnS because of the high melting point as a characteristic of the II-VI compound and the high vapor ratio of nitrogen in the composition.

Vacuum evaporation method and sputtering method are known as methods for obtaining ZnS single crystals, but due to the above reasons, crystalline temporary
1.It is not a method that gives satisfaction in terms of purity. or,
Molecular beam epitaxy growth method (hereinafter MB
(referred to as the E method), and high-quality Z rI S using it.
Until now, there has been no report on the formation of small crystal films.

(c) Aim of the invention A first object of the invention is to provide a high-quality ZnS single crystal film with color forming dimensions.

(d) Structure of the invention The present invention uses the MBE method.

The conventional Z n S m crystal film growth method using the MBE method is generally 'A'=' (7) According to the MBE method,
A source of Zn (zinc) and a source of S (sulfur) were used, and each source did not dissipate 1 ZnSdi atom. In particular, since S is hygroscopic, the source itself was exposed to H2O.
and 02, and the steam ratio is high, making it difficult to control.

The present inventor succeeded in growing a high-quality ZnS single crystal by paying attention to the selection of the source in the MBE method and specifying the substrate crystal, substrate temperature, and crystal growth rate. That is, the characteristics of the method of the present invention are that single crystal or polycrystalline ZnS is used as a source, the substrate temperature is 230 to 280°C, the growth rate is 0.
．． 4- Under the condition of IL m/hr, molecular beam Evita kinial growth is performed on (ioo > There is a particular thing.

(P) A preferred embodiment uses a single crystal or polycrystalline ZnS with a high purity of 6N or higher as a source, and sets the temperature of the <100) GaP substrate to 260°C and the growth rate to 06 μm/hr. This is the MBE method. In other respects, this method is the same as the normal MBE method.

FIG. 1 shows the relationship between the source ZnS vapor in the growth chamber and the growth rate, and FIG. 2 shows the relationship between the substrate temperature and the growth rate. In FIG. 1, the substrate temperature If is 260° C., and in FIG. 2, the source vapor pressure is approximately 4×1O−7 Torr.

Furthermore, Fig. 3 shows the (400) of the grown cubic ZnS film.
The relationship between the lattice constant determined from the X-ray diffraction spectrum that appears as the main direction and the substrate temperature is shown in Figure 4. -4゜In Figures 3 and 4, saw-J
75. The air ΣF is approximately 4×10−7 Torr, and point A in FIG. 4 has a growth rate of 2.5, Ll m/hr, and a source vapor ratio of 1×10 Torr. When Ohne electron spectroscopy was performed on the crystal film, the ratio of Zn to S was found to be ylo.

In the present invention, in addition to GaP, GaA
s, or one with a case (・constant) of the same degree as these is fine.
,reactor! Although the crystal film No. 1 has a high resistance, a low resistance film can be obtained by appropriate doping.

Effects of the invention: (According to the invention, a high-quality ZnS crystal film can be obtained, and therefore a good blue light-emitting device can be formed.
By using a GaP substrate, GaP red and green light emitting device technology has already been completed, and by combining this, a seven-color three-color light emitting device can be obtained. or,
Since the substrate is glued 100) and used lv), the cleavage direction is at an angle of 90°, making chip processing easy.

[Brief explanation of drawings]

1 to 4 are measurement curve diagrams for explaining the present invention. The Basic Fragility of Basara (°C) Neo Anti〕5 & (°Otsu)

Claims (1)

[Claims] (1) Using jij, crystalline or polycrystalline ZnS as a source, the base jij 1M degree 230-280'C1 growth rate Jn
0.4-1 p m/h+ as /I, G
a P or GaAs (J with a rated r constant of the same order as 1)
, (100) of one ton crystal substrate! Z
n5-jlj crystal film J & Nagano J method.