Modeling of dual-metal Schottky contacts based silicon micro and nano wire solar cells

TL;DR

This paper models silicon micro and nano wire solar cells with dual-metal contacts, analyzing how wire dimensions, metal work functions, and carrier lifetimes influence photovoltaic performance, and proposes interdigitated designs for efficiency improvements.

Contribution

It introduces a detailed model of dual-metal contact silicon wire solar cells, exploring effects of various parameters and proposing interdigitated designs to enhance performance.

Findings

Maximum efficiency occurs with one Schottky and one Ohmic contact.

Short circuit current and open circuit voltage increase with wire length before saturation.

Interdigitated multi-contact design can improve photovoltaic response.

Abstract

We study solar cell properties of single silicon wires connected at their ends to two dissimilar metals of different work functions. Effects of wire dimensions, the work functions of the metals, and minority carrier lifetimes on short circuit current as well as open circuit voltage are studied. The most efficient photovoltaic behavior is found to occur when one metal makes a Schottky contact with the wire, and the other makes an Ohmic contact. As wire length increases, both short circuit current and open circuit voltage increase before saturation occurs. Depending on the work function difference between the metals and the wire dimensions, the saturation length increases by approximately an order of magnitude with a two order magnitude increase in minority carrier length. However current per surface area exposed to light is found to decrease rapidly with increase in length. The use of a multi-contact interdigitated design for long wires is investigated to increase the photovoltaic response of the devices.