Wafer processing method including uniting wafer, ring frame and polyolefin sheet without using an adhesive layer
US11587832B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 13, 2020 |
| Grant date | Feb 21, 2023 |
| Priority date | — |
| Expiry date | May 15, 2041 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2221/68327
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A wafer processing method includes a polyolefin sheet providing step of positioning a wafer in an inside opening of a ring frame and providing a polyolefin sheet on a back side or a front side of the wafer and on a back side of the ring frame, a uniting step of heating the polyolefin sheet as applying a pressure to the polyolefin sheet to thereby unite the wafer and the ring frame through the polyolefin sheet by thermocompression bonding, a dividing step of applying a laser beam to the wafer to form shield tunnels in the wafer, thereby dividing the wafer into individual device chips, and a pickup step of cooling the polyolefin sheet, pushing up each device chip through the polyolefin sheet, and picking up each device chip from the polyolefin sheet.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.