Impact of Temperature and Indium Composition in the Channel on the Microwave Performance of Single-Gate and Double-Gate InAlAs/InGaAs HEMT

This paper presents an accurate charge control-based analytical model for investigating the impact of temperature variation in a broad range from -50 °C to 200 °C and the impact of indium composition variation in the channel on the small-signal equivalent circuit parameters of single-gate (SG) and double-gate (DG) In_0.52Al_0.48As/In_mGa_1-mAs (0.53 ≤ m ≤ 0.8) high electron mobility transistor (HEMT). The drain current and the various small-signal equivalent circuit parameters including the transconductance and the gate capacitances which are considered as the major factors governing the microwave performance of the device are observed to be more sensitive to temperature variation in the case of DG-HEMT as compared to the SG-HEMT. The increase in the indium composition in the In m Ga_1-mAs channel from to results in improved cutoff frequency of the device. However, the degradation in the cutoff frequency with increase in temperature increases with increase in the indium content in the channel. The results obtained from the proposed analytical model are compared and found to be in good agreement with the ATLAS device simulation results.