To set the operating voltage of a field electron/emission surge absorber element to a comparably low value by jointing its frame member to its first substrate member, and by providing thereafter the thickness adjusting process of its frame member, and further, by utilizing its first substrate member as a reinforcing member of its frame member.
On a hot plate, a first substrate member 11 is mounted by making its first external electrode 23 face its lower side, and an electrode plate 43 is stuck pressingly on a second end-surface 13b of a frame member 13. With the first external electrode 23 of the first substrate member 11, the plus side of a DC power supply 44 is connected to, have its negative side connected with the electrode plate 43. With the hot plate, the first substrate member 11 and the frame member 13 are heated, and from the DC power supply 44, a DC voltage is applied across the electrodes 23, 43. By making positive ions in the frame member 13 migrate to the negative side of the DC power supply 44 after the lapse of a fixed time, negative charges concentrate in the vicinity of the peripheral edge of the opposite surface of the first substrate member 11 to the second end-surface 13b and a space-charge layer appears therein to realize an anodic junction. After completing the anodic junction the second end-surface 13b of the frame member 13 is polished by a whetstone 47, to adjust the required height of the frame member 13 Thereby, the operating voltage of a field-electron/emission type surge absorbing element can be set low.
MARUYAMA MITSUHARU
MISAWA MASAYOSHI
YONEKUBO TAKASHI
NAGANO PREFECTURE