The effects of cap layer thickness on the performance of InGaN/GaN MQW solar cell

TL;DR

This paper presents a theoretical study on how varying the cap layer thickness in InGaN/GaN MQW solar cells affects their efficiency, showing that thicker cap layers improve key performance metrics.

Contribution

It introduces a theoretical model analyzing the impact of cap layer thickness on quantum efficiency and electrical performance of InGaN/GaN MQW solar cells.

Findings

Thicker cap layers lead to higher quantum efficiency.

Increasing cap layer thickness improves short circuit current density.

A 3.2% increase in fill factor is observed with thicker cap layers.

Abstract

Following letter introduces a theoretical approach to investigate the effect of two-step GaN barrier layer growth methodology on the performance of InGaN/GaN MQW solar cell, in which a lower temperature GaN cap layer was grown on top of each quantum well followed by a higher temperature GaN barrier layer. Different growth conditions would cause changes in the concentration of trap level density of states and imperfection sites. The simulation and comparison of 3 samples each with different cap layer thickness, reveals the fact that increasing cap layer thickness results in higher quantum efficiency, improved short circuit density of current and 3.2% increase of the fill factor.