P沟MOSFET/FIPOS的γ射线总剂量辐照特性

Total dose γ-ray radiation characteristics of P-channel MOSFET/FIPOS

采用高选择和自终止多孔氧化硅全隔离技术制备了高质量的ＳＯＩ材料。研究了在该材料上采用２μｍＣＭＯＳ工艺制备的不同沟道长度的Ｐ沟ＭＯＳＦＥＴ的６０Ｃｏγ射线总剂量辐照特性，表明经５ｋＧｙ（Ｓｉ）辐照后，器件仍有特性，但阈值电压有较大的漂移，这主要是由栅氧化层中的辐照感生电荷而引起。不同沟道长度ＰＭＯＳＦＥＴ的辐照特性基本相同。经一段时间室温退火，阈值电压出现回漂。

The high quality SOI(silicon on insulator) materials were prepared with highly selective and self-stopping full isolation by porous oxidized silicon(FIPOS) technology. The PMOSFETs with different channel lengths were fabricated by the 2 μm CMOS process on the SOI wafers and their total dose 60Co γ- ray radiation characterietics were studied. The reaults show that the devices remain functional after 5kGy(Si) dose radiation, but the threshold voltage has a significant shift. The main factor causing this shift is the radiation- induced trapped- oxide charge in the gate oxide layer. The devices with different channel lengths have similar radiation characteristics. After room- temperature annealing for several hours, the threshold voltage has a little back- shift.