Novel Channel Structures for High Frequency InP-Based HTEFs

Takatomo ENOKI, Kunihiro ARAI, Tatsushi AKAZAKI, Yasunobu ISHII

Summary :

We discuss delay times derived from the current gain cutoff frequency of a heterostructure field effect transistor and describe three types of novel channel structures for millimeter-wave InP-based HFETs. The first structure discussed is a lattice-matched InGaAs HEMT with high state-of-the art performance. The second structure is an InAs-inserted InGaAs HEMT which harnesses the superior transport properties of InAs. Fabricated devices show high electron mobility of 12,800 cm²/Vs and high transconductance over 1.4 S/mm for a 0.6-µm-gate length. The effective saturation velocity in the device derived from the current gain cutoff frequency in 3.010⁷ cm/s. The third one is an InGaAs/InP double-channel HFET that utilizes the superior transport properties of InP at a high electric field. Fabricated double-channel devices show kink-free characteristics, high carrier density of 4.510¹² cm^-2 and high transconductance of 1.3 S/mm for a 0.6-µm-gate length. The estimated effective saturation velocity in these devices is 4.210⁷ cm/s. Also included is a discussion of the current gain cutoff frequency of ultra-short channel devices.

• Publication: IEICE TRANSACTIONS on Electronics Vol.E76-C No.9 pp.1402-1411
• Publication Date: 1993/09/25
• Type of Manuscript: Special Section PAPER (Special Issue on Heterostructure Electron Devices)

Authors

Takatomo ENOKI
Kunihiro ARAI
Tatsushi AKAZAKI
Yasunobu ISHII

Keyword

InGaAs,  InAs,  InAlAs,  InP,  current gain cutoff frequency,  delay times,  heterojunction FET,  quantum well,  real-space transfer