We report the results of an extensive study employing numerous methods to characterize carrier transport within copper indium gallium sulfoselenide (CIGSS) photovoltaic devices, whose absorber layers were fabricated by diverse process methods in multiple laboratories. This collection of samples exhibits a wide variation of morphologies, compositions, and solar power conversion efficiencies. An extensive characterization of transport properties is reported here -including those derived from capacitance-voltage, admittance spectroscopy, deep level transient spectroscopy, time-resolved photoluminescence, Auger emission profiling, Hall effect, and drive level capacitance profiling. Data from each technique were examined for correlation with device performance, and those providing indicators of related properties were compared to determine which techniques and interpretations provide credible values for transport properties. Although these transport properties are not sufficient to predict all aspects of current-voltage characteristics, we have identified specific physical and transport characterization methods that can be combined using a model-based analysis algorithm to provide a quantitative prediction of voltage loss within the absorber. The approach has potential as a tool to optimize and understand device performance irrespective of the specific

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This contribution is a summary of a workshop convened to discuss the characterization and modeling of thin‐film CuInSe2(CIS)‐based solar cells, 17‐19 October 1993, in Estes Park, Colorado. the participants of the workshop are the authors of this paper. the subject matter was examined along four lines: device modeling, characterization, processing, and manufacturing issues. Fundamental numerical modeling has successfully guided device design efforts, including the design of variable band‐gap absorbers. Quantitative analysis, however, has been compromised by incomplete data on fundamental material properties. Phenomenological modeling and device characterization have sucessfully contributed to the understanding of the device physics. Although classified as a heterojunction device, the forward‐current recombination of the ZnO/CdS/CIS occurs almost exclusively in the space‐charge with diode quality factors ranging from 1.2 to 1.7 for good devices. the next generation of device modeling must incorporate two‐ and three‐dimensional effects. Recent fabrication work has focused on improving the CIS absorber and adding Ga and S to the matrix to increase its band‐gap. A better understanding of the ternary's fundamental properties is required to support the modeling efforts. Control of Ga and S introduction and the resulting absorber band‐gap profiles will facilitate the realization of optimized device designs. Inadequate understanding of fundamental device operation and process control at the laboratory level are amplified in the manufacturing environment. Modeling and characterization can identifv areas where corrective actions will result in improved performance and yield at the module level.