Title :
High-performance 94-GHz single balanced mixer using 70-nm MHEMTs and surface micromachined technology
Author :
Kim, Sung Chan ; An, Dan ; Lim, Byeong Ok ; Baek, Tae Jong ; Shin, Dong Hoon ; Rhee, Jin Koo
Author_Institution :
Millimeter-wave Innovation Technol. Res. Center, Dongguk Univ., Seoul, South Korea
Abstract :
We reported 94-GHz, low conversion loss, and high isolation single balanced active gate mixer based on 70-nm gate length InGaAs/InAlAs metamorphic high-electron mobility transistors (MHEMTs). This mixer showed that the conversion loss and isolation characteristics were 2.5∼3.5 dB and under -29 dB in the range of 92.95∼94.5 GHz, respectively. The low conversion loss of the mixer is mainly attributed to the high-performance of the MHEMTs exhibiting a maximum drain current density of 607 mA/mm, an extrinsic transconductance of 1015 mS/mm, a current gain cutoff frequency (ft) of 330 GHz, and a maximum oscillation frequency (fmax) of 425 GHz. High isolation characteristics are due to hybrid ring coupler which adopted dielectric-supported air-gapped microstrip line structure using surface micromachined technology. To our knowledge, these results are the best performance demonstrated from 94 GHz single balanced mixer utilizing GaAs-based HEMTs in terms of conversion loss as well as isolation characteristics.
Keywords :
HEMT circuits; III-V semiconductors; aluminium compounds; coupled circuits; current density; gallium arsenide; indium compounds; isolation technology; micromachining; microstrip lines; millimetre wave circuits; millimetre wave mixers; 330 GHz; 425 GHz; 70 nm; 94 GHz; GaAs; InGaAs-InAlAs; dielectric-supported air-gapped microstrip line; hybrid ring couplers; isolation characteristics; low conversion loss; metamorphic high-electron mobility transistors; single balanced active gate mixer; surface micromachined technology; Current density; Cutoff frequency; HEMTs; Indium compounds; Indium gallium arsenide; Isolation technology; MODFETs; Mixers; Transconductance; mHEMTs; 70-nm; Dielectric-supported air-gapped microstrip line (DAML); hybrid ring coupler; metamorphic high-electron mobility transistors (MHEMTs); single balanced mixer;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2005.861403