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:
Dec. 03, 2002
Filed:
Oct. 10, 2000
Ying Chou Tsai, Hsinchu, TW;
Shih Kuang Chiu, Taichung, TW;
Abstract
A flip-chip packaging process is proposed, which can help assure reliable electrical bonding between chip-side solder bumps and substrate-side bond pads without being made open-circuited by the electrically-insulative material being used for flip chip underfill. The proposed flip-chip packaging process is of the type utilizing a no-flow underfill technique to prevent short-circuiting between neighboring solder bumps, and is characterized in the fabrication of electrically-conductive sharp-pointed studs over substrate-side bond pads to prevent open-circuiting between chip-side solder bumps and substrate-side bond pads. These electrically-conductive sharp-pointed studs can pierce into the chip-side solder bumps when mounting the flip chip onto the substrate, so that during subsequent solder-reflow process, the piercing of these sharp-pointed studs in the solder bumps can help allow the solder bumps to be reliably wetted to the substrate-side bond pads, thereby establishing reliable electrical bonding between the chip-side solder bumps and the substrate-side bond pads. The finished flip-chip device is therefore more assured in quality and reliability.