Dividing method for wafer having film on the front side thereof
US7897488B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 19, 2009 |
| Grant date | Mar 1, 2011 |
| Priority date | — |
| Expiry date | Jul 16, 2029 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K2103/50
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A wafer dividing method for dividing a wafer having a film on the front side thereof. The wafer dividing method includes a modified layer forming step of applying a laser beam having a transmission wavelength to the substrate of the wafer from the front side thereof along the streets so that a focal point of the laser beam is set inside the substrate, thereby forming a modified layer in the substrate along each street, a film dividing step of applying a laser beam having an absorption wavelength to the film from the front side of the wafer along each street to thereby form a laser processed groove for dividing the film along each street, a back grinding step of grinding the back side of the substrate of the wafer to thereby reduce the thickness of the wafer to a predetermined thickness, a wafer supporting step of attaching the wafer to a dicing tape supported to an annular frame, and a wafer breaking step of applying an external force to the wafer by expanding the dicing tape to thereby break the wafer along each street.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.