Bonded grid-cathode electrode structure
US4405878A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 1, 1981 |
| Grant date | Sep 20, 1983 |
| Priority date | — |
| Expiry date | Oct 1, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J9/18
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A variety of technologies have been applied in the development of a bonded rid cathode. Erosion lithography is used for making the fine-detail grid structure, combining air erosion and lithographic techniques. To obtain openings of the order of 0.001 inch (one mil) or smaller, a nozzle with a high aspect ratio exit opening is used, and the cathode grid structure is scanned. A photo resist in which the grid pattern is developed is used over the molybdenum or tungsten grid film. The metal film is removed from the grid openings by chemical etching. The photo resist over the metal grid is used as a composite mask for removing the BN insulation in the openings by erosion with Al.sub.2 O.sub.3 powder from the special nozzle on the air blast gun.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.