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:
Jul. 08, 2008
Filed:
Jan. 31, 2005
Applicant:
Eddy Kunnen, Kessel-Lo, BE;
Inventor:
Eddy Kunnen, Kessel-Lo, BE;
Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L 21/8228 (2006.01);
U.S. Cl.
CPC ...
Abstract
A method for forming deep trench or via airgaps in a semiconductor substrate is disclosed comprising the steps of patterning a hole in the substrate, partly fill said hole with a sacrificial material (e.g. poly-Si), depositing spacers on the sidewalls of the unfilled part of the hole (e.g. TEOS) to narrow the opening, removing through said narrowed opening the remaining part of the sacrificial material (e.g. by isotropic etching) and finally sealing the opening of the airgap by depositing a conformal layer (TEOS) above the spacers. The method of forming an airgap is demonstrated successfully for use as deep trench isolation structures in BiCMOS devices.