A 2-D model of the grooved solar cell has been developed, based on an approximate analysis that allows the obtaining of a closed-form solution of the fundamental transport equations of the device. This model represents a flexible tool for the analysis of the cell, for understanding the basis of its operation, and as a design tool. In order to assess the validity of the proposed model, the analytical solution is also compared with a full 2-D solution, obtained from PISCES simulation.
A significant improvement in the performance of Silicon solar cells has been achieved in recent years with the so-called laser grooved cell /1/. In these cells, the top contact is formed within deep grooves, formed on the cell surface by laser ablation. This cell structure has demonstrated to achieve very high efficiencies exceeding, in some cases, 20% /2/.
An analysis of the bipolar operation of vertical JFET structures is performed by splitting the device into two quasi-one-dimensional structures. Detailed analytical solutions are obtained for carrier and field distributions, for the saturation voltage, the output ID-VDS curves and current gain. The results are able to predict the performance of experimental devices and provide an insight into the physics of this operating mode of vertical JFET's.
