摘要 |
<p><P>PROBLEM TO BE SOLVED: To stably provide an electron source capable of maintaining high reliability even at an operation for long period. <P>SOLUTION: On the electron source, in which electron emitting material composed of hexaboride of rare earth element is interposed between a pair of heating elements, and the heating elements are held by a pair of conductive supports, an insulation film is formed at an area not contacting the electron emitting material of the heating element and the conductive support. It is preferable for the electron source that the heating element is made of carbon, and the insulation film is made of boron nitride, more preferably, the insulation film is made of pyrolytic boron nitride. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |