Influence of Source-Gate and Gate Lengths Variations on GaN HEMTs Based Biosensor

AlGaN/GaN has been considered as a promising candidate for bio-sensing applications due to their outstanding properties. Scaling of gate length and source to gate length plays a key role in the performance of biosensor as it directly influences the device transconductance and hence the sensitivity and response time of biosensors. In this paper, we investigated the effect of variations in gate lengths (1–5 μm) and source to gate length (1–3 μm) to choose the most suitable one for bio sensing applications. Downscaling of gate length (L

G

) and source to gate length (L

SG

) improve the device performance, enhancing the drain-current (I

ds

) and device transconductance. The results of simulations indicate that L

G

1 μm_L

SG

1μm with constant L

SD

configuration shows highest output current 1.01 A/mm, transconductance (g

m

) 211 mS/mm with lowest value of gate leakage current. Irrespective of L

SG

, effect of variation in L

G

follows same trend.