Cadmium stannate-based transparent conductive film, production process thereof and solar cell

Abstract

The present application provides a cadmium stannate-based transparent conductive film, production process thereof and solar cell. In the production process of the present application, first a target material is subjected to magnetron sputtering in an oxygen-containing gas environment, then a transition film layer is composited, and is then annealed in a protective atmosphere. The preparation method according to the invention can be directly annealed in a protective atmosphere without a close-to-annealing mode, thus greatly simplifying the annealing process and realizing industrialized large-scale production. The invention also provides a cadmium stannate-based transparent conductive film and a solar cell comprising the cadmium stannate-based transparent conductive film, wherein the electric and optical properties of the cadmium stannate-based transparent conductive film provided by the invention are obviously improved compared with an existing commercial TCO film.

Description

technical field [0001] The invention relates to the technical field of solar cells, in particular to a cadmium stannate-based transparent conductive film, its production process and a solar cell. Background technique [0002] Cadmium telluride (CdTe) thin-film solar cell is a commercial high-efficiency solar cell, and its conventional structure is as follows: figure 1 As shown, it includes substrate glass-TCO transparent conductive film-window layer-CdTe absorption layer-transition layer-metal contact electrode, wherein the TCO transparent conductive film is the front electrode of the solar cell, and its function is to generate Carriers can be collected effectively while reducing the energy loss caused by its own resistance. Since the conventional cadmium telluride solar cell is a light-incoming structure, in order to improve the utilization rate of sunlight, more light needs to enter the semiconductor absorption layer and convert it into electron-hole pairs, thereby conver...

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Problems solved by technology

However, in this preparation process, during annealing, it is necessary to perform face-to-face annealing of the CdS film and the CTO film on the substrate. When there is a problem with the flatness of the substrate surface, it is easy to cause unevenness of the CTO film; It is not suitable for large-scale automated assembly line technology. Even if an additional mechanical structure is designed to assist the annealing of the membrane surface, it will greatly increase the difficulty of industrialized large-scale automated production.

In addition, the CdS film layer is used many times, which is easy to contaminate impurities, thereby further contaminating the CTO film layer, making the performance of the CTO less than the expected effect, and bringing uncontrollable factors to the stability of the process; in addition, annealing often requires ℃ or even higher temperature, which exceeds the softening temperature of ordinary glass substrates, and requires the use of special high-temperature-resistant substrates. This annealing method greatly increases the production cost of the film material and limits industrial scale production.

Therefore, in the prior art, CTO membranes can only be prepared and researched in the laboratory, but it is difficult to achieve large-scale industrial production.

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