Simulation of Zinc-diffused InAs cells for low temperature thermophotovoltaic systems

We simulated zinc-diffused InAs cells which used in the low-temperature thermophotovoltaic system under 600-1200 degrees C blackbody radiation. By analyzing some important parameters, such as surface recombination speed or thickness of different InAs cells, we achieve the optimal cell structure. The Zn diffusion process was experimented at Zn-In alloy sources at different temperatures for 2 h and a box-shaped Zn profile with a single hump was obtained. We also performed a simulation for optimized GaSb structure. Unlike InAs cells, the GaSb cells have been investigated for a long time under various temperatures, from which we have obtained a better structure and a maximal efficiency of 30%. However, the output power density of InAs cells is greater than that of GaSb cells when applied under low temperature heat source below 1200 degrees C. Its open circuit voltage and short circuit current density were measured as 0.1157 V and 3.786 A, and the output power density was 0.2222 W/cm(2), which is better than 0.098 W/cm(2) of GaSb cell under a blackbody temperature of 800 degrees C with anti-reflection coating and 13.7% grid area. The improved performance can be attributed to its lower bandgap and better quantum efficiency (QE) curves.

Automated summary

This study investigates the optimal performance of zinc-diffused InAs cells and optimized GaSb structure under low-temperature heat source. The output power density of InAs cells is shown to be greater than that of GaSb cells when applied under 600-1200 degrees C blackbody radiation.