Temperature-Dependent Characteristics of a Pseudomorphic High Electron Mobility Transistor with Graded Triple Delta-Doped Sheets

Abstract

The temperature-dependent characteristics of an interesting InGaP∕InGaAs double-channel pseudomorphic high electron mobility transistor with graded triple δ-doped sheets are systematically studied and demonstrated. By using the graded triple δ-doped sheets and InGaAs double-channel structure, the studied device exhibits temperature-dependent dc and microwave characteristics well. Experimentally, for a 0.8×100μnormalm2 gate device, the high turn-on voltage of 1.06 (0.88)V , low gate leakage current of 76 (411)μA∕mm at VGD=15V , high maximum transconductance of 175 (151.5)mS∕mm with 1.6 (1.33)V broad operating regime (0.9normalgm,max) , low output conductance of 0.56 (0.59)mS∕mm , and high voltage gain of 306 (259) are obtained at 300 (450)K , respectively. Furthermore, good device performance with low-temperature variation coefficients under the operating range from 300to450K is obtained. Moreover, good agreements between the simulated analysis and experimental results are found.

Temperature-Dependent Study of AlGaAs/InGaAs Integrated Depletion/Enhancement-Mode High Electron Mobility Transistors with Virtual Channel Layers

“…As mentioned above, the improved threshold voltage behavior of the Dmode device is caused by the better performance of metal-semiconductor interface. Furthermore, the considerably low temperature coefficients on threshold voltage measured is superior to the previous reports of the related GaAs-substrate transistors, 19,20 such as the InGaP/InGaAs/GaAs PHEMT with ∂V th /∂T of −1.33 mV K −119 and the InGaAs/InAlAs metamorphic HEMT with −1.21 mV K −1 . 20…”