On some features of a new electron emission microscope.

Abstract

The article deals with the essential features of a new electron emission microscope, special attention being paid to the vacuum system and the objective lens. The vacuum of the order of 10 ntorr is attained in the specimen chamber with the help of an ion-getter pump, and the spectrum of residual gases is checked continuously during the operation. The rest of the optical system is evacuated by a conventional vacuum system with automatic valving. A specimen air-lock contributes to quick cycles of operation. Different kinds of emission microscopy are possible with the instrument. An example of the favourable influence of improved vacuum conditions in case of tunnel emission is given at the end.