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:
Sep. 28, 1999
Filed:
Aug. 26, 1997
Masayuki Ochiai, Kawasaki, JP;
Fujitsu Limited, Kanagawa, JP;
Abstract
A plate used for fabricating metal bumps is made from a silicon having a <110> crystallographic plane. The plate has a flat surface arranged at an angle relative to the <110> crystallographic plane, and cavities are formed in the flat surface by anisotropic etching. Each of the cavities has a rhombic opening and two oblique bottom surfaces defining a deepest portion. The deepest portion is shorter than the diagonal line of the rhombus and positioned in the cavity near one end thereof. In the method for fabricating metal balls, the cavities are filled with a paste containing metal particles, and heated to form metal balls in the cavities. The metal balls are then transferred from the plate to an electronic device.