Device physics for engineering design of heavily doped regions in pn-junction silicon solar cells / by Muhammed Ayman Shibib.

Abstract

This dissertation presents a quantitative study of the physical mechanisms underlying the anomolously large recombination current experimentally observed in heavily doped regions of silicon pn-junction solar cells and bipolar transistors. The study includes a comparison of theoretical predictions with a variety of experimental observations in heavily doped silicon and silicon devices. A major conclusion is that the simplest physical model that adequately describes the heavily doped regions must include Fermi-Dirac statistics, a phenomenological excess intrinsic carrier density (or deficit impurity concentration), Auger recombination in the bulk, and recombination at the surface. These mechanisms are incorporated in a first-order model useful in the design of silicon pn-junction solar cells. The accuracy of the first-order model is supported by comparing its results with the results of more detailed models and of a numerical vn analysis of the problem. Experimental data are presented that are consistent with the predictions of the first-order model and of the numerical solution. VI 11 CHAPTER I to Auger recombination are responsible for the large emitter recombination currents observed in pn-junction devices.