Radiation-hardness of VA1 with Sub-micron
M. Yokoyama, H. Aihara, M. Hazumi, H. Ishino, J. Kaneko, Y. Li, D. Marlow, S. Mikkelsen,
E. Nyg°ard, H. Tajima, J. Talebi, G. Varner, and H .Yamamoto
Abstract-- We have studied the radiation hardness of the
VA1, a Viking-architecture preamplifier VLSI chip. LSI
samples are fabricated in 0.8 µm and 0.35 µm process tech-
nologies to improve the radiation hardness of the LSI for
the Belle silicon vertex detector upgrade.
We have observed significant improvement of the radia-
tion hardness with 0.8 µm technology. Little degradation of
noise and gain is observed up to a total dose of 20 Mrd for
the VA1 fabricated in the 0.35 µm technology. We find that
the radiation hardness improves with a scaling of better than
ox (tox: oxide thickness). Basic parameters of MOS FETs
are also studied to understand the mechanism of radiation
damage in the VA1.