Laser-heated emission of electrons from a carbon-coated metal surface and its application to the emissive probe measurements.

An electron source utilizing the CO(2) laser-heated electron emission from a carbon-coated metal surface has been experimentally studied. This type of emission may have the advantage that no potential gradient exists in the vicinity of the metal surface and emission from a surface of very small dimension and of arbitrary shape can be easily obtained. Experimental emission current characteristics for various target temperatures were given and discussed. An application to the emissive probe for measuring the plasma space potential is shown. The results obtained by the emissive probe are also checked independently by using the rf probe method.