Method for making multilayer devices using only a single critical masking step
US3957552A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1975 |
| Grant date | May 18, 1976 |
| Priority date | — |
| Expiry date | Mar 5, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/0574
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method for making multilayer devices, such as magnetic bubble domain devices, which are comprised of a plurality of layers that are deposited using only a single critical masking step. A first metallic layer is deposited on a substrate including a magnetic bubble domain film, which may or may not have a nonmagnetic material thereon. A first resist layer is then applied, selectively exposed, and developed to expose at least two areas of the first metallic film. A thicker metallic layer is then deposited in the exposed areas, or is electroplated. After this, another resist layer is applied without deforming the pattern in the first layer, selectively exposed, and developed to protect certain areas of the thick metallic layer from subsequent formation of another metallic layer. During this subsequent formation, a second metallic film is formed using the first resist layer as a mask. After this, the resists are removed and the now uncovered portions of the original thin metallic layer are etched away. In a particular embodiment, a magnetic bubble domain chip is provided in which the second resist layer is used to protect the sensor region of the chip. The second resist layer need not…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.