Sub 0.1 Micrometer Asymmetric Gamma-Gate PHEMT Process Using Electron Beam Lithography
Abstract
In this paper, we have studied on the fabrication of GaAs-based pseudomorphic high electron mobility transistors (PHEMT's) for the purpose of millimeter-wave applications. To fabricate the high performance GaAs-based PHEMT's, we have developed unit processes, such as 0.1 micrometer GAMMA-gate lithography, silicon nitride passivation, and air-bridge process to achieve high performance of device characteristics. The DC characteristics of the fabricated PHEMT was measured at a unit gate width of 70 micrometers and 2 gate fingers, and showed a good pinch-off property (V (sub p) = -1 V) and a drain-source saturation current density (I (sub dss)) of 373.53 mA/mm. Maximum extrinsic transconductance (g(sub m) was 522.4 mS/mm at V( sub gs) = -0.3 V, V( sub ds) = 1.5 V, and I( sub ds) = 0.5 I( sub dss). The RF measurements were performed in the frequency range of 1.0 ^ 50 GHz. For this measurement, the drain and gate voltage were 1.5 V and -0.3 V, respectively. At 50 GHz, 9.2 dB of maximum stable gain (MSG) and 4.2dB of S(sub 21) gain were obtained, respectively. A current gain cut-off frequency (f( sub tau)) of 113 GHz and a maximum frequency of oscillation (fmax) of 180 GHz were achieved from the fabricated PHEMT with a 0.1 micrometer gate length.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 03, 2003
- Accession Number
- ADP013354
Entities
People
- Dong Hoon Shin
- J. K. Rhee
- W. S. Sul
Organizations
- Dongguk University