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:
Nov. 06, 2001
Filed:
Mar. 22, 1999
Sony Corporation, Tokyo, JP;
Abstract
To realize an ohmic electrode having practically satisfactory characteristics relative to GaAs semiconductors, first formed on an n,-type GaAs substrate are a Ni thin film with a thickness between 8 nm and 30 nm, an In thin film with a thickness between 2 nm and 6 nm and a Ge thin film with a thickness between 10 nm and 50 nm, sequentially. After that, the n,-type GaAs substrate having formed the Ni thin film, In thin film and Ge thin film is annealed at a temperature between 300 to 600° C. for a few seconds to minutes. As a result, the ohmic electrode has a multi-layered structure including an n,-type re-grown GaAs layer re-grown from the n,-type GaAs substrate, InGaAs layer and NiGe thin film. Alternatively, before the annealing, a thin film of a refractory metal or its compound, such as Nb thin film, with or without another thin film of a wiring metal, such as Au thin film, may be further formed on the Ge thin film.