Low-hydrogen photovoltaic cell

Abstract

A low-hydrogen photovoltaic cell is disclosed. The photovoltaic cell may contain less than 5% hydrogen. In one aspect, the photovoltaic cell may contain substantially no hydrogen, that is, the photovoltaic cell may be substantially hydrogen free. The photovoltaic cell includes a substrate and an absorber deposited on to the substrate. The absorber may typically include elements from group 11, group 12, and group 13 of the Periodic Table, for example, copper, indium, and gallium. The absorber may be treated with selenium and / or sulfur to produce a CIGS or CIGSS-type photovoltaic cell. The low-hydrogen photovoltaic cell may fabricated by a method and apparatus adapted to control metalloid vapor delivery, for example, in a low-hydrogen or hydrogen free atmosphere.

Description

CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application is a divisional application of co-pending application Ser. No. 11 / 282,934 filed on Nov. 18, 2005 [attorney docket no. 2606.002], the disclosure of which is incorporated by reference herein in its entirety.TECHNICAL FIELD OF THE INVENTION [0002] The present invention relates to methods and apparatus for exposing a material or work piece to a vaporous element. Specifically, the present invention provides methods and apparatus for treating a photovoltaic precursor with a vaporous element, for example, selenium or sulfur, to produce thin film CIGS or CIGSS solar cells. BACKGROUND OF THE INVENTION [0003] The limited availability of and environmental concerns about fossil fuels make them increasingly less attractive as a means to produce electricity. As a result of this trend, alternative energy sources, particularly solar energy, are becoming more popular. While solar energy is a reliable and dependable energy source, the co...

AI Technical Summary

Benefits of technology

[0019] The present invention provides methods and apparatus for treating materials with vaporous elements and compounds that enhances the versatility and adaptability of the treatment process. Though aspects of the invention may be utilized in the manufacture and processing of photovoltaic material, aspects of the invention are not limited to processing photovoltaic material, but can be applied to the treatment of any material where the control and regulation of treatment temperature impacts the cost, quality, or performance of the product produced.

Problems solved by technology

Eberspacher discloses a method to form a CIS or CIGS film without using H2Se, which is a highly toxic gas and is thus unsuitable for large scale manufacturing because of safety concerns.

Beck distinguishes the first CIGS process of the Chen species as undesirable for industrial scale manufacturing because of high temperatures to form the absorber matrix.

Beck further distinguishes the second selenization process of the Ermer species as undesirable because of the use of highly toxic H2Se, low selenium utilization, and poor adhesion to molybdenum coated substrates.

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