Device Performance Analysis for Different Gate Locations in AlGaN/GaN HEMT by Silvaco Simulation

AlGaN/GaN-based high electron mobility transistors (HEMTs) with different gate locations have been simulated in Silvaco. The current-voltage analysis suggests that placing the gate nearer to the source results in a higher saturation current. This happens as the voltage nearer to the source is less than comparable to the drain. This causes lesser reverse bias across the gate metal-semiconductor junction. Thus a HEMT with gate contact near the source is very useful for high-power applications. At the same time, noise analysis of the devices suggests that the minimum noise figure, for the HEMTs where the gate contact is placed nearer to the source contact is higher than its counterparts. This creates some reliability issues in semiconductor devices. The possible reason behind such a phenomenon has also been discussed in thiswork.