Stress-induced selective-area lift-off of thin films and devices on van der Waals buffer layers
US11361999B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 5, 2021 |
| Grant date | Jun 14, 2022 |
| Priority date | — |
| Expiry date | Jan 5, 2041 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2221/68368
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for making a selective-area lift-off thin film comprises depositing a van der Waals (vdW) buffer on a substrate; depositing a thin film material (or device structure) on the van der Waals buffer; depositing an adhesion layer on the thin film material; forming a stressor layer on top of the thin film layer; and bonding a handle layer to the stressor layer. Force may be applied to the layered structure by one or more of rolling, bending, and shearing. The area selected for lift-off may be defined by one of laser cutting and mechanical scribing. The vdW buffer includes one or more of hBN, graphite, and graphene. The handle layer is a one of a polyimide tape, thermal release tape, UV release tape, water- or solvent-soluble tape, Kapton tape, and Scotch tape. The stressor layer is a metal film, e.g. Ni, Cr, Ti.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.