The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 05, 1999
Filed:
Apr. 10, 1997
Chanh N Nguyen, Newbury Park, CA (US);
Nguyen Xuan Nguyen, Oxnard, CA (US);
Minh V Le, Simi Valley, CA (US);
Hughes Electronics Corporation, El Segundo, CA (US);
Abstract
A process is provided for fabricating MODFET's in group III nitride compound semiconductors. The process precedes isolation of the MODFET structure with the use of e-beam lithography to define very narrow (e.g., .about.0.25 micrometer) gates which enhance transistor microwave cut-off frequency. Because these compound semiconductors resist chemical etchants, isolation is accomplished by etching with reactive ions to form an isolation mesa having a vertical mesa sidewall. To improve breakdown, the mesa sidewall is covered with a passivation layer prior to deposition of a gate feed that contacts the gate. To reduce parasitic gate capacitance, the gate feed is spaced from a narrow edge of the transistor's two-dimensional electron gas.