Measurement techniques for multijunction solar cells

Various types of multijunction cells, including monolithic, mechanically stacked, two, three, four, and six-terminal, are reviewed along with various interconnection techniques. Since different measurement techniques are appropriate for accurately measuring the cell performance of each type of multijunction cell, the key issues in obtaining accurate results under various standardized conditions are also discussed. The equipment and techniques needed to measure the efficiencies of those cells are described. Specific measurement results are presented for a three-junction solar cell which consists of an AlGaAs/GaAs monolithic cell mechanically stacked above an InGaAs cell grown on a separate GaAs substrate