Numerical simulation of Ge solar cells using D-AMPS-1D code

M. BARRERA; F. RUBINELLI; I. REY STOLLE; J. PLÁ

Buenos Aires

Workshop; At the Frontiers of Condensed Matter V; 2010

Comisión Nacional de Energía Atómica

A solar cell is a solid state device that converts the energy of sunlight directly into electricity by the photovoltaic effect. When light with photon energy greater than the band gap is absorbed by a semiconductor material, free electrons and free holes are generated by optical excitation in the material. The main characteristic of a photovoltaic device is the presence of internal electric field able to separate the free electrons and holes so they can pass out of the material to the external circuit before they recombine. Numerical simulation of photovoltaic devices plays a crucial role in their design, performance prediction, and comprehension of the fundamental phenomena ruling their operation. The electrical transport and the optical behavior of the solar cells discussed in this work were studied with the simulation code D-AMPS-1D. This software is an updated version of the one-dimensional (1D) simulation program AMPS (Analysis of Microelectronic and Photonic Devices) that was initially developed at The Penn State University, USA, during the years 1988-1993. Structures such as homojunctions, heterojunctions, multijunctions, etc., resulting from stacking layers of different materials can be studied by appropriately selecting characteristic parameters such as the gap energy, carrier mobilities, absorption coefficients among others. In this work, examples of cells simulation made with D-AMPS-1D are shown. Particularly, results of Ge photovoltaic devices are presented. The role of the InGaP buffer on the device were studied. Moreover, a comparison of the simulated electrical parameters with experimental results was performed.