Planarization process for thin film surfaces
US6922890B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 15, 2002 |
| Grant date | Aug 2, 2005 |
| Priority date | — |
| Expiry date | Jun 10, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T156/1153
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method is provided for planarization of structures which minimizes step heights, reduces process steps, improves cleanliness, and provides increased ease of debond. Structures are placed with working surfaces facing down onto an adhesive layer such that structures remain fixed during heating. A bi-layer encapsulating film is used to achieve planarization. A carrier is bi-laminated with a thermoplastic film layer followed by a chemically inert protective polymer film layer that can withstand etch and cleaning processes. The thermoplastic layer is laminated on top of the carrier; the polymer layer is laminated on top of the joined thermoplastic layer and carrier. The carrier with bi-layer film is then placed onto the backside of the structures to resist chemical attack from the front side during photostrip and enable planarization. When heat is applied, the bi-layer encapsulating film melts and pushes the polymer layer into the gaps between structures thereby achieving complete planarization.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.