Depletion and enhancementmode modulationdoped fieldeffect transistors for ultrahighspeed applications: an electrochemical fabrication technology

Dong Xu, Tetsuya Suemitsu, Jiro Osaka, Yohtaro Umeda, Yasuro Yamane, Yasunobu Ishii, Tetsuyoshi Ishii, Toshiaki Tamamura

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)

Abstract

This paper is devoted to an electrochemicaletchingbased technology for fabricating highperformance MODFET's for highspeed applications. The electrochemical etching in the gate openings is induced by the exposure of the Ni surface metal on the ohmic electrodes. It results in very slender gaterecess grooves which are desirable for highspeed MODFET's because of the resulting achievable small gatetochannel separation and low parasitic resistance. The technology is easy to implement and is effective for enhancing the aspect ratio. Good control of aspect ratio is essential for achieving excellent device performance and limiting deleterious shortchannel effects. Successful vertical scaling together with minimization of gate length by wellestablished electronbeam lithography using fullereneincorporated electronbeam resist leads to the realization of both optimal D and Emode MODFET's with ultrahigh extrinsic transconductance values and current gain cutoff frequencies. Fully passivated 0.07nm DMODFET's with 2.25 S/mm extrinsic transconductance and current gain cutoff frequency exceeding 300 GHz have been successful fabricated. In addition 0.03|m EMODFET's with 2 S/mm transconductance and 300 GHz current gain cutoff frequency have been demonstrated. This electrochemicaletchingbased technology provides both highperformance D and EMODFET's and therefore opens up the possibility to achieve ultrahighspeed IC's based on DCFL configurations.

Original languageEnglish
Number of pages1
JournalIEEE Transactions on Electron Devices
Volume47
Issue number1
Publication statusPublished - 2000 Dec 1
Externally publishedYes

Keywords

  • Electrochemical processes
  • Electronbeam lithography
  • Epitaxial growth
  • Etching
  • Highspeed circuits/devices
  • MODFETS
  • Millimeter wave fet's
  • Semiconductor device fabrication
  • Semiconductor heterojunctions

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Electrical and Electronic Engineering

Fingerprint

Dive into the research topics of 'Depletion and enhancementmode modulationdoped fieldeffect transistors for ultrahighspeed applications: an electrochemical fabrication technology'. Together they form a unique fingerprint.

Cite this