ANALYSIS OF SILICON SOLAR-CELLS INCORPORATING AN EXTRA DEFECT RICH LAYER

Recently, it has been reported that the efficiency of a crystalline silicon solar cell had been strongly increased by implanting a thin defect layer absorbing light at higher wavelengths, thus causing additional light generations. In this work the effects of a such layer on the electric properties of a c-Si and an a-Si solar cell are theoretically explored. In the examination of the most favorable position of the defect layer in the cell and its effect on solar cell characteristics, a piecewise analytical approach was used dividing the solar cell structure into segments and maintaining the continuity of electric properties at interfaces between these segments. Using this approach it was deduced that a slight increase of short-circuit current - accompanied by a greatly increased dark current lowering the efficiency - can be expected in a c-Si cell, whereas in case of an c-Si cell the added defect layer results in a degradation of all relevant solar cell parameters.