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:
Aug. 07, 2007
Filed:
Jun. 17, 2005
Rowland C. Clarke, Sykesville, MD (US);
Erica C. Elvey, Owings Mills, MD (US);
Silai V. Krishnaswamy, Monroeville, PA (US);
Jeffrey D. Hartman, Severn, MD (US);
Rowland C. Clarke, Sykesville, MD (US);
Erica C. Elvey, Owings Mills, MD (US);
Silai V. Krishnaswamy, Monroeville, PA (US);
Jeffrey D. Hartman, Severn, MD (US);
Northrop Grumman Corporation, Los Angeles, CA (US);
Abstract
First and second semiconductor wafers are bonded together, with at least one of the wafers having a first layer of silicon, an intermediate oxide layer and a second layer of silicon. The first silicon layer is initially mechanically reduced by around 80% to 90% of its thickness. The remaining silicon layer is further reduced by a plasma etch which may leave an uneven thickness. With appropriate masking the uneven thickness is made even by a second plasma etch. Remaining silicon is removed by a dry etch with XeF2 or BrF3 to expose the intermediate oxide layer. Prior to bonding, the semiconductor wafers may be provided with various semiconductor devices to which electrical connections are made through conducting vias formed through the exposed intermediate oxide layer.