JPS6065723A - Heat treatment of sintered film of cadmium sulfide - Google Patents

Abstract

PURPOSE:To improve adhesivity of sintered film of CdS to a soda-lime glass substrate, by printing CdS paste containing CdCl2 on the soda-lime glass substrate, sintering it in a N2 atmosphere, heat-treating this CdS film in an air atmosphere. CONSTITUTION:Powder of cadmium sulfide is blended with cadmium chloride and an organic binder to give cadmium sulfide paste. This paste is printed on a soda-lime glass, predried, sintered in a nitrogen gas atmosphere to give a cadmium sulfide film. This cadmium sulfide film is then heat-treated in an air atmosphere at 460-500 deg.C for <=10min. The annealing treatment is ineffective in an atmosphere of H2, N2, or CO2, but excellent effect is shown in an air atmosphere. Since quality of CdS film is deteriorated by the action of O2, sintering is carried out in a nitrogen gas.

Description

Detailed Description of the Invention The present invention provides a soda glass substrate and a cadmium sulfide sintered film (
Hereinafter, this will be referred to as a CdS sintered film. ) to improve the adhesion of
The present invention relates to a heat treatment method for S sintered film.

Conventionally, expensive borosilicate glass (Pyrex, etc.) with high heat resistance has been used as a substrate material for CdS. This is because the sintering temperature of CdS is 650 DEG C. to 700 DEG C., which is low and inexpensive, and glass substrates could not be used.

Therefore, so-called photoconductor elements (light receiving elements) formed using such materials have been expensive.

Afterwards, as a result of research on the sintering method of CdS, it was found that by using cadmium chloride (hereinafter referred to as CdCj2) as a fluxing agent, 540'C~5
It was found that a high quality CdS sintered film could be formed in a temperature range of 65°C, making it possible to use a soda glass substrate, and making the device significantly cheaper.

However, the CdS sintered film formed by this method on a soda glass substrate has a large internal stress, and may self-destruct even when left alone, or easily peel off when washed with water, making it impractical. was there.

This means that the thermal expansion coefficient of soda glass is 9° x 1σ
This is thought to be due to the fact that the coefficient of thermal expansion of borosilicate glass is three times that of borosilicate glass, whereas the coefficient of thermal expansion of soda glass is 54 cm.
It is thought that the sintering temperature range of 0°C to 565°C is also a contributing factor.

The purpose of the present invention is to eliminate such drawbacks of the prior art,
Cd-
8. An object of the present invention is to provide a heat treatment method that improves the adhesion between a sintered film and a soda glass substrate.

To achieve this objective, the present invention provides CdS powder with
A CdS paste is made by adding CaCl2 and an organic binder, the paste is printed on a soda glass substrate, this is pre-dried, and the resulting CdS film is sintered in a nitrogen gas (N2) atmosphere. 460° at
All characteristics are that heat treatment is performed within 10 minutes at a temperature range of 500°C to 500°C.

The present invention will be explained below using examples.

First, a CdS paste is made by adding a flux CdCt2 and an organic inder to CdS powder, and the paste is printed on a soda glass substrate.

Next, after pre-drying this, it is sintered in a N.

Using the thus obtained CdS film on the soda glass substrate as a material, experimental results of heat treatment, that is, annealing treatment, of this material will be described below.

(1) There was no effect of annealing in N2, N2, and CO2 atmospheres.

On the other hand, in an air atmosphere, the effect of annealing treatment was noticeable. This revealed that the adhesion between the CdS film and the soda glass substrate had a strong correlation with σ)02 in air.

(2) The annealing temperature needs to be 460°C or higher.

The CdS film was completely maintained in an air atmosphere of 460°C or higher, and with the elapsed time, 0. The surface of the CdS film (■) turned reddish and changed into sulfates and oxides, showing severe deterioration.

(3) From the above, in the annealing process (σ) in an air atmosphere, the adhesion between the Cdsm and the substrate is improved by the action of the atom, and the CdS film quality is 0. It was found that the deterioration occurred due to the action of

(4) Next, regarding these contradictory effects, changes in the adhesion strength of the CdS film and the quality of the CdS film with respect to the annealing treatment time were investigated.

FIG. 1 is a relationship diagram showing the state of adhesion strength of a CdS film on a soda glass substrate with respect to annealing treatment time when annealing treatment is performed at a temperature of 500° C. using an air atmosphere furnace.

FIG. 2 shows the change in the quality of the CdS film formed as a so-called light-receiving element with respect to the annealing time when annealing was performed under the same conditions as in FIG. 1, and the open-circuit voltage V at the terminal of the light-receiving element. It is a relationship diagram shown as a decrease in the absolute value of 0.

As is clear from Figure 1, the effect of annealing the CdS film in air occurs in an extremely short time; for example, the adhesion strength can reach 100% just by holding it at a temperature of 500°C for 1 minute. Reached.

Further, even when the holding time was extended to 10 minutes and 20 minutes, there was no increase or decrease in the adhesion strength.

Concerning changes in CdS film quality - As is clear from Figure 2, no change in the electrical properties of CdS film was observed during the annealing treatment at 500°C for 1 to 10 minutes;
At holding times of 0 minutes or more, the electrical characteristics, ie, V. 0
An abnormality occurred in the value of , and the generation of minute foreign crystals was observed on the surface of the CdS film.

Therefore, from the above, annealing treatment in an air atmosphere at 460°C to 500°C for 10 minutes or less can produce CdS [soda glass substrates and CdS without deterioration in quality].
A CdS sintered film with excellent adhesion between dS films and suitable for a so-called light receiving element was obtained.

As explained above, in the present invention, a fILCdS film suitable for a photoconductor element, a so-called light receiving element, is sintered in an N atmosphere on the cheapest soda glass substrate, and then the CdS film is sintered in an N atmosphere.
The adhesion between the CdSi and the soda glass substrate is significantly improved by a simple method of subjecting the S film to a short-time annealing treatment in a desired atmosphere, and the effect is extremely large.

[Brief explanation of the drawing]

Figure 1 is a relationship diagram showing the state of adhesion strength between the soda glass substrate and CdS film as a function of annealing treatment time, and Figure 2 is a relationship diagram showing changes in CdS film quality as changes in electrical characteristics as a function of annealing treatment time. be.

Claims (1)

[Claims] Cadmium sulfide paste is made by adding cadmium chloride and an organic binder to cadmium sulfide powder, and the paste is printed on a soda glass substrate, and after pre-drying, it is placed in a nitrogen gas atmosphere. Cadmium sulfide film obtained by sintering in an air atmosphere. Cadmium sulfide sintering, characterized in that heat treatment is performed within 10 minutes at a temperature range of 460 ° C to 500 ° C,
Membrane heat treatment method.