Yj. Yoon et al., SILICON VACUUM MICRODIODE WITH ON-CHIP ANODE, Journal of vacuum science & technology. B, Microelectronics and nanometer structures processing, measurement and phenomena, 12(2), 1994, pp. 648-651
A vacuum microdiode was fabricated with a silicon avalanche cathode an
d an on-chip microanode. The image reverse process followed by proper
heat treatment was employed to form a photoresist sacrificial layer in
shaping a microanode. The distance of approximately 3 mum between cat
hode and anode was achieved by adjusting the number of depositions of
photoresist. On the top of the sacrificial layer, a multilayer (Al/TiW
/Al) structure was deposited, which provided the microanode with good
conductivity and mechanical strength. The dimension of the microanode
was 8 (or 18) mum in width and more than 30 mum in length. The I-V cha
racteristics of this vertical-type microdiode demonstrated the enhance
ment of current emission due to a strong electric field at relatively
low anode voltages.