Fabrication of SiN-assisted 0.12um AlGaAs/InGaAs PHEMT and 60GHz-band MMICs for 60GHz WPAN system


In this paper, the fabrication technology of SiN-assisted 0.12um double deck T-gate AlGaAs/InGaAs p-HEMT and 60GHz-bands MMICs for the high rate personal area network (WPAN) system was described. The effect of the gate shape such as the 1st-deck and the 2nd-deck gate head size on the DC and RF characteristics of the p-HEMT device and the device performance at the optimum gate head size were also presented. At 0.22um of the optimum 1st-deck gate head size and 1um of the 2nd-deck head size, the p-HEMT device with two finger gates of 0.12um length × 50um width shows an extrinsic transconductance of 529mS/mm and a threshold voltage of -1.19V. The cut-off frequency and the maximum frequency of oscillation were 94.7GHz and 189.1GHz, respectively. The gate shape of the p-HEMT device such as a gate head size is correlated to parasitic capacitances including Cgs which have effects on RF performances including a cut-off frequency (fT) and a maximum frequency of oscillation (fmax).

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Correspondence to Hokyun Ahn.

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Ahn, H., Lim, JW., Ji, HG. et al. Fabrication of SiN-assisted 0.12um AlGaAs/InGaAs PHEMT and 60GHz-band MMICs for 60GHz WPAN system. MRS Online Proceedings Library 969, 310 (2006). https://doi.org/10.1557/PROC-0969-W03-10

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