Semiconductor wafer coat layers and methods therefor

US7279362B2 · kind B2 · utility

Assignee

• Intel Corporation · US

Inventors

• Eric J. Li · Chandler, US
• Daoqiang Lu · Chandler, US
• Christopher L. Rumer · Chandler, US
• Paul A. Koning · Cumming, US
• Darcy E. Fleming · Tempe, US
• Gudbjorg H. Oskarsdottir · Chandler, US
• Tiffany Byrne · Chandler, US

Key dates

• Filing date: Mar 31, 2005
• Grant date: Oct 9, 2007
• Expiry date: May 15, 2025

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L2924/14
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

Formulations and processes for forming wafer coat layers are disclosed. In one embodiment, an organic surface protectant is incorporated into a wafer coat formulation deposited onto a semiconductor wafer prior to the laser scribe operation. Upon removal of the wafer coat layer, the organic surface protectant remains on the bumps and thereby prevents oxidation of the bumps between die prep and chip and attach. In an alternative embodiment, an ultraviolet light absorber is added to the wafer coat formulation to enhance the wafer coat layer's energy absorption and thereby improve the laser's ability to ablate the wafer coat layer. In an alternative embodiment, a conformal wafer coat layer is deposited on the wafer and die bumps, thereby reducing wafer coat layer thickness variations that can impact the laser scribing ability.