Control of charge-up on insulating glass in vacuum due to plasma processing

In order to control charge-up on insulating glasses used for high-voltage vacuum equipment, H/sub 2/ plasma processing on the glass surface was studied. Borosilicate glass plates were used as test samples. The glasses were exposed to H/sub 2/ plasma produced by AC (60 Hz) voltage application. The surface resistivity of the glass was deceased with H/sub 2/ plasma processing time. By H/sub 2/ plasma exposure for 20 minutes, the surface resistivity was reduced from 10/sup 17/ /spl Omega/ to 10/sup 12/ /spl Omega/. Due to the reduction of the surface resistivity, charge-up of the glass irradiated by electron beam can be controlled to the level not to cause surface flashover.