Method of porosifying part of a semiconductor wafer
US11810779B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 16, 2022 |
| Grant date | Nov 7, 2023 |
| Priority date | — |
| Expiry date | Jun 16, 2042 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D62/111
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method includes: in a semiconductor wafer having a first semiconductor layer and a second semiconductor layer adjoining the first semiconductor layer, forming a porous region extending from a front surface into the first semiconductor layer; and removing the porous region by an etching process, wherein a doping concentration of the second semiconductor layer is less than 10−2 times a doping concentration of the first semiconductor layer and/or a doping type of the second semiconductor layer is complementary to a doping type of the first semiconductor layer, wherein forming the porous region comprises bringing in contact a porosifying agent with the front surface of the first semiconductor layer and applying a voltage between the first semiconductor layer and a first electrode that is in contact with the porosifying agent, wherein applying the voltage comprises applying the voltage between the first electrode and an edge region of the first semiconductor layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.