Optimization of π – Gate AlGaN/AlN/GaN HEMTs for Low Noise and High Gain Applications

Abstract

This paper presents a comprehensive TCAD based assessment to evaluate the intrinsic gain and minimum noise figure metrics of the T -Gate, and the π -Gate AlGaN/AlN/GaN HEMTs along with their recessed architectures. The work presented in this paper, to the best of author's knowledge, is first in its attempt to systematically bring out both the effect of minimum noise figure metrics and intrinsic gain at the device level for the π -Gate architecture and their recessed counterparts whilst evaluating its stability for high frequency operations. Comparison demonstrates an enhancement in intrinsic gain by 64.5% in case of asymmetric π -Gate and 77% for asymmetric recessed π -Gate in comparison to their T -Gate counterparts. Further, the said architectures possess a wider range of flat gain operation with suppressed values of minimum noise figure metrics. These modifications result in a modest trade off in the minimum noise figures when best case is considered and compared with their T -Gate counterparts. Additionally, it is also demonstrated that such device architectures demonstrate much stable high frequency operation in comparison to their primer. The results so presented establish the superiority of the π -Gate AlGaN/ AlN/GaN HEMTs for low noise and high gain applications.

Multilayer perceptron–random forest based hybrid machine learning–neural network model for GaN high electron mobility transistor's parameter estimations

“…The device has been virtually fabricated in Silvaco Atlas Simulation Deck, and the simulation methodology is as per Ref. 17. Starting with a SiC substrate, an AlN nucleation layer (40 nm), GaN buffer layer (2.5 μm), and AlN spacer (1 nm) layer was deposited.…”

“…A novel Π-gate architecture was presented by Alvaro et al, 14 which is proved to have a better thermal and reliable RF performance. Detailed analysis on the various prospects and optimization of Π-gate design was presented by Sehra et al [15][16][17] However, the greatest challenge in the device design and optimization is the convergence complexity and time requirements during simulation and parameter extraction when dealing with conventional TCAD tools.…”

Impact of AlGaN Barrier Thickness and Substrate Material on the Noise Characteristics of GaN HEMT

“…Increasing the number of gate fingers and reducing the gate width of each finger was shown useful in reducing the gate resistance [13] and hence it was shown to improve the noise performance [12]. For T-and pi-gate GaN HEMT structures, variation of the NF with the gate bias in the C and X bands was studied in [14]. The recessed T-gate structure exhibited better noise performance when compared with the pi-gate structure.…”

60 GHz Double Deck T-Gate AlN/GaN/AlGaN HEMT for V-Band Satellites

“…It suppresses the dispersion and electric field to improve the device reliability [18]. Pi-gate restricts the electron acceleration near the gate edges reducing the hot electron effects [19]. On the other hand, T gate diminishes the gate resistance and enhances the cut-off frequency (fT).…”