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. 24, 2020
Filed:
Dec. 11, 2014
Luminus, Inc., Sunnyvale, CA (US);
Saijin Liu, San Jose, CA (US);
Luminus, Inc., Sunnyvale, CA (US);
Abstract
Methods and apparatus are provided to improve the yield rate of LED packaging using LED flip chips. In one novel aspect, extended pads made of sintered silver are disposed on the cathode and the anode of the LED flip chip. The thickness of the extended pad is from about 25 μm to about 200 μm. In another embodiment, the LED flip chip further comprises a phosphor layer such that the LED flip chip emits white light. In another novel aspect, the LED flip chip with extended pads made of sintered silver is produced at the wafer level. The wafer level process involves applying sintering silver pastes to the cathode and the anode of each LED flip chip formed on the wafer and sintering the wafer at a temperature about 180° C. to about 240° C. for about two hours. The wafer is cut to individual LED flip chips with extended sintered silver pads.