Nanoporous GaN by UV assisted electroless etching for sensor applications

Abstract

GaN-based devices have demonstrated excellent performance for electronics and optoelectronics applications. In particular, these devices exhibit very good performance when operated at high temperatures and in harsh environments when compared to similar devices fabricated with conventional material systems. The good stability, durability and biocompatibility of the nitrides have also led to the development of GaN based chemical and biological gas sensors. These devices have been developed using Schottky diodes with platinum or palladium contacts on GaN and AlGaN/GaN structures [1-3] and showed high sensitivity. However, the response may be further improved if the effective surface área is increased, allowing a more efficient accumulation of the gas induced dipole layer [4]. In this paper fabrication and characterization of nanoporous GaN is presented as a fírst step for the fabrication of improved GaN gas sensors.