Electron beam evaporator having beam spot control
US4064352A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 17, 1976 |
| Grant date | Dec 20, 1977 |
| Priority date | — |
| Expiry date | Feb 17, 1996 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/305
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electron beam evaporator employs an electron gun which projects a beam of electrons over an arcuate beam path to a crucible target for heating and evaporating the target material in use. The electron beam passes through the magnetic field supplied by a pair of pole pieces of a beam focus magnet which produces a main field transverse to the direction of the electrons to cause the beam to take the arcuate trajectory. Two pairs of auxiliary pole pieces project inwardly of the main pole pieces to provide a pair of beam focus lenses. One of the magnetic lenses is disposed on the inside of the beam path, whereas the other is disposed on the outside of the beam path to provide beam lateral focusing and defocusing lenses, respectively. The lenses are adjustable, preferably electromagnetically for controlling the beam spot size on the target crucible so that the evaporation characteristics can be optimized for a given beam power. In addition, the magnetic lenses are adjustable, preferably electromagnetically, for sweeping the position of the beam spot longitudinally and/or laterally of the crucible target.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.