Silvaco ATLAS as a solar cell modeling tool

This paper presents research efforts conducted at the Naval Postgraduate School in the development of an accurate, physically-based solar cell model using the general-purpose ATLAS device simulator by Silvaco International. Unlike solar cell models based on a combination of discrete electrical components, this novel model extracts the electrical characteristics of a solar cell based on virtual fabrication of its physical structure, allowing for direct manipulation of materials, dimensions, and dopings. In addition, our model has the ability to accurately simulate more advanced solar cell design features including doping gradients, optical properties, back-surface fields, back-surface reflectors, windows, carrier traps, contact grid shading and complex light spectra. Available outputs include I-V characteristics, photogeneration mapping, and spectral response. The operation of the ATLAS software is described in detail and our model is applied to known single junction and multijunction solar cell designs. The results of the solar cell simulation in ATLAS are compared and shown to be similar to published experimental results.