Improved performance of InGaN/GaN multiple-quantum-wells photovoltaic devices on free-standing GaN substrates with TMAH treatment

Photovoltaic PV devices necessitate both superior electrical properties and optical absorption due to their unique operational requirements. This study introduces a method using TMAH treatment to simultaneously enhance these characteristics in InGaN/GaN PV devices fabricated on free-standing GaN substrates. By eliminating surface defects on the sidewalls of mesas, which are caused by dry etching, the electrical properties are improved. Concurrently, the creation of textured morphologies on the back surfaces of the devices enhances optical absorption. These different effects of improvements are attributed to the anisotropic chemical resistance of the GaN crystal. This method significantly enhances the performance of InGaN/GaN PV devices.