  We are developing monolithic pixel detectors based on SOI technology for high
energy physics, X-ray applications and so on.To employ SOI pixel detector on
such radiation environments, we have to solve effects of total ionizing dose
(TID) for transistors which are enclosed in oxide layer.The holes which are
generated and trapped in the oxide layers after irradiation affect
characteristics of near-by transistors due to its positive electric
field.Annealing and radiation of ultraviolet are not realistic to remove
trapped holes for a fabricated detector due to thermal resistance of components
and difficulty of handling. We studied compensation of TID effects by tunneling
using a high-voltage. For decrease of trapped holes, applied high-voltage to
buried p-well which is under oxide layer to inject the electrons into the oxide
layer.In this report, recent progress of this study is shown.
