Single lithography for multiple-layer bubble domain devices
US4001061A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1975 |
| Grant date | Jan 4, 1977 |
| Priority date | — |
| Expiry date | Mar 5, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F41/34
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A fabrication process for fabricating multiple layer magnetic bubble domain devices using only a single masking step. As a specific example, a thin conductor film (which could be a magnetic material, such as NiFe) is deposited on a substrate comprising a magnetic bubble domain material. This conductor film is coated with a resist which is exposed with an electron beam or an X-ray beam. The exposure density in a first area of the resist is different than that in a second area of the resist. Subsequent development of the resist will uncover the thin film only in the area which has received the greater exposure density. This area can then be used as a plating base for electro-plating another conductive layer, such as a thick gold film. Further development of the resist is used to uncover the second area (which initially received a lower exposure density). Another layer then can be plated which will plate onto the thin conductive base film which is now uncovered and onto the second conductive layer which was formed in the previous electro-plating step. After this, the remaining resist and the unwanted remaining thin film is etched away to leave a final circuit structure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.