High Performance Split-Gate-Trench MOS Based on Radiation-Hardening Technology and Its Total-Ionizing-Dose Radiation Effects

In this paper, a novel radiation-hardened SGT(N-SGT) is firstly developed by employing a specialized Total-Ionizing-Dose radiation hardening process and the radiation degradation model is proposed. At the TID dose of 100 krad (Si), the
$\vert \Delta V_{th}\vert$
of N-SGT is only 0.16 V, reduced by 87.7%, and it's BV is 32.5V, increased by 44.4% compare with Conventional-SGT. To evaluate the radiation damage on oxide layer, the irradiated induced charges, including
$Q_{GOX},Q_{IPOX}$
and
$Q_{TROX}$
, has been extracted by T-CAD. Due to lower irradiated induced
$Q_{GOX}, Q_{IPOX}$
and
$Q_{TROX}$
in N-SGT, the channel depletion and DIBL effect are weakened, and the charge imbalance is alleviated. The lower proportion of
$Q_{IPOX}:Q_{TROX}$
(1:3) in N-SGT improved the tolerance to the irradiated charge. In addition, this paper firstly reveals that the
$C_{gd}$
of C-SGT significantly increases after irradiation, due to the impact of
$Q_{IPOX}$
and
$Q_{GOX}$
on channel depletion and charge imbalance. Fortunately, N-SGT has more stable capacitance characteristics after irradiation and achieves a good trade-off.