Normally-Off AlGaN/GaN MOSHEMT as Lebel Free Biosensor
S. N. Mishra, Rajesh Saha, K. Jena
Abstract
In this paper, a systematic analytical model of biosensing parameters such as transfer characteristic, output characteristic, channel potential, transconductance-to-drain current ratio ( g m /I ds ),change in threshold voltage (ΔV Th ), and sensitivity for a dielectric modulated normally off AlGaN/GaN metal oxide semiconductor high electron mobility transistor (MOSHEMT) is reported. A detailed analysis of the concept of gate cavity dielectric modulation in MOSHEMTs is performed with focus on the enhancement of sensing parameters to signify the presence of biomolecules such as Streptavidin, Biotin, and APTES. The accuracy of the model result is validated through Technology Computer Aided Design (TCAD) device simulator by incorporating nano gaps in MOSHEMT structure as well as suitable physics-based mathematical models are considered in simulation. Results highlighted a new view points and deep insight the design of Normally off AlGaN/GaN MOSHEMT-based dielectric modulated biosensors. Furthermore, this heterostructure provide a useful approach towards biomolecular detection and meeting the demand of interdisciplinary novel semiconductor device design.