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. 20, 2001
Filed:
Apr. 24, 2001
Raymond J. E. Hueting, Helmond, NL;
Cornelis E. Timmering, Eindhoven, NL;
Henricus G. R. Maas, Eindhoven, NL;
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
In the manufacture of semiconductor devices that have an electrode (,) in an insulated trench (,), for example a trench-gate MOSFET, process steps are performed to line the trench walls with a lower insulating layer (,) in a lower part of the trench and with a thicker upper insulating layer (,) in an upper part of the trench. The steps include: (a) etching the trench (,); (b) providing the lower insulating layer (,) on the trench walls; (c) depositing on the lower insulating layer (,) a further layer (,) of a different material; (d) depositing on the further layer (,) a filler material (,) that is of a different material from the further layer (,); (e) etching away the further layer (,) from the upper part of the trench walls while using the filler material (,) as an etchant mask, so as to form a space (,) adjacent to the upper part of the trench walls while leaving the further layer (,) in the lower part of the trench; and (f) providing the thicker upper insulating layer (,) in the space (,) adjacent to the upper part of the trench walls.