Uniformity investigation of pHEMTs small-signal parameters for pre and post multilayer fabrication in 3D MMICs

Abstract

The main aim of this paper is to investigate the uniformity of pHEMTs small-signal parameters before and after multilayer fabrication in 3D MMICs. Seven samples of pre-and post-multilayer fabricated pHEMTs at different representative locations to reflect the degree of consistency. This study deals with the fabrication, measurement, simulation, and comparison of both sample in form of means and slandered deviation. On wafer scattering (S-) parameter measurement has been accomplished to investigate the small signal equivalent circuit parameters up to 50 GHz. The main finding was observed that all parameters are increased after multilayer fabrication except the transconductance and the parasitic inductances. The employment of the 3D-MMIC technology does not induce any evident extinction of the pHEMTs performance utilizing seven different samples of pre-and post-multilayer fabrication.

Thermal Sensitivity of Microwave Pseudomorphic High‐Electron‐Mobility Transistor Performance: Pre and Post Multilayer Technology

“…A traditional "cold" pinch-off method was used to obtain the values of the ECPs. [24][25][26] Table 1 reports the values of the drain current, transconductance, threshold voltage, the ECPs, the intrinsic input and feedback time constants (i.e., τ gs ¼ R gs C gs and τ gd ¼ R gd C gd ), the unity current gain cut-off frequency ( f t ), and the maximum frequency of oscillation ( f max ) at the reference temperature (T 0 ) of 25 C. The intrinsic non-quasi-static (NQS) effects that occur in response to rapid signal changes from the intrinsic device's inertia are modeled by the three intrinsic time constants (τ m , τ gs , and τ gd ). The f t and f max values are determined from the measured short-circuit current gain (h 21 ) and maximum stable/available gain (MSG/MAG), respectively.…”

Measurement-based Investigation of the DC and RF Transconductance for Various HEMT Technologies in High-and Low-temperature Conditions

“…Therefore, the total gate width of multi-finger devices is given by the product of the number of fingers and their length. To develop highly integrated monolithic microwave integrated circuits (MMICs), HEMT devices might be realized using the multi-layer three-dimensional (3-D) technology [6][7][8].…”