Linear and Circular AlGaN/AlN/GaN MOS-HEMT-based pH Sensor on Si Substrate: A Comparative Analysis

In this article, sensitivity enhancement of undoped AlGaN/AlN/GaN HEMT for pH detection by using dielectric (10 nm Al2O3)-based MOS-gated structure is demonstrated. Linear and circular MOS-HEMT (L-MOSHEMT and C-MOSHEMT, respectively) with similar dimensions are fabricated on Si substrate. Novel sensing metric gd/IDS (drain conductance to current ratio) is introduced, and C-MOSHEMT attains the high...