High performance thin solar cell

A silicon solar cell was designed which has collecting junctions on both the illuminated and dark sides. The characteristics of the two junctions are interdependent, thus the cell is called a Tandem Junction Cell (TJC). The photoresponse I-V performance of cells was measured with either collection from both sides or collection from only the nonilluminated side. Current collected from both sides of a 100 micrometer thick TJC cell was approximately 46mA/cm²(AMO), with the maximum expected at 30-50 micrometers. Current collected from the nonilluminated side only was 34 mA/cm²for 125 micrometer cell and 45 mA/cm²is expected for 30-50 micrometer thickness. The performance of the TJC is forecast to yield a Vocof 0.6V, Iscof 50 mA/cm²for an efficiency of approximately 18% (AMO, 25°C). Comparison of the experimental and calculated current collection results shows close agreement.