Method for removing a bulk substrate from a bonded assembly of wafers
US10727216B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 10, 2019 |
| Grant date | Jul 28, 2020 |
| Priority date | — |
| Expiry date | May 10, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D88/00
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A first wafer including a first substrate, first semiconductor devices overlying the first substrate, and first dielectric material layers overlying the first semiconductor devices is provided. A sacrificial material layer is formed over a top surface of a second wafer including a second substrate. Second semiconductor devices and second dielectric material layers are formed over a top surface of the sacrificial material layer. The second wafer is attached to the first wafer such that the second dielectric material layers face the first dielectric material layers. A plurality of voids is formed through the second substrate. The sacrificial material layer is removed by providing an etchant that etches a material of the sacrificial material layer through the plurality of voids. The substrate is detached from a bonded assembly including the first wafer, the second semiconductor devices, and the second dielectric material layers upon removal of the sacrificial material layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.