Process for bonding micromachined wafers using solder
US6062461A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 3, 1998 |
| Grant date | May 16, 2000 |
| Priority date | — |
| Expiry date | Jun 3, 2018 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB81C1/00269
- WIPO fieldMicro-structural and nano-technology
- WIPO sectorChemistry
Abstract
A method by which semiconductor wafers (10, 12) can be solder bonded to form a semiconductor device, such as a sensor with a micromachined structure (14). The method entails forming a solderable ring (18) on the mating surface of a device wafer (10), such that the solderable ring (18) circumscribes the micromachine (14) on the wafer (10). A solderable layer (20, 26, 28) is formed on a capping wafer (12), such that at least the mating surface (24) of the capping wafer (12) is entirely covered by the solderable layer (20, 26, 28). The solderable layer (20, 26, 28) can be formed by etching the mating surface (24) of the capping wafer (12) to form a recess (16) circumscribed by the mating surface (24), and then forming the solderable layer (26) to cover the mating surface (24) and the recess (16) of the capping wafer (12). Alternatively, the solderable layer (28) can be formed by depositing a solderable material to cover the entire lower surface of the capping wafer (12), patterning the resulting solderable layer (28) to form an etch mask on the capping wafer (12), and then to form the recess (16), such that the solderable layer (28) covers the mating surface (24) but not the surfaces …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.