Laser processing method for wafer
US10573559B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 19, 2018 |
| Grant date | Feb 25, 2020 |
| Priority date | — |
| Expiry date | Nov 19, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/67092
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A laser processing method for a wafer includes: linearly forming a plurality of shield tunnels each having a fine hole and an amorphous region surrounding the fine hole at predetermined intervals in an inner part of a test substrate, the test substrate having a material and a thickness identical to those of a substrate of the wafer to be processed, while changing time intervals of a plurality of pulses constituting a burst pulse laser beam; and measuring a rupture strength when the test substrate is ruptured along the plurality of shield tunnels. Next, the time intervals of the pulses when the rupture strength is at a minimum are calculated, and a laser processing step is performed which linearly forms a plurality of shield tunnels at predetermined intervals in an inner part of the wafer, by irradiating the wafer with the laser beam having the time intervals of the pulses.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.