Analysis of bias effects on the total ionizing dose response in a 180 nm technology

详细信息    查看全文

• 作者：Zhangli Liu^a ; ^b ; ^{liuzhangli@mail.sim.ac.cn"" rel=""nofollow} ; Zhiyuan Hu^a ; ^b ; Zhengxuan Zhang^a ; Hua Shao^a ; Ming Chen^a ; ^b ; Dawei Bi^a ; Bingxu Ning^a ; ^b ; Shichang Zou^a
• 关键词：Bias condition ; Oxide trapped charge ; Shallow trench isolation ; Substrate bias ; Total ionizing dose
• 刊名：Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
• 出版年：2011
• 出版时间：11 July 2011
• 年：2011
• 卷：644
• 期：1
• 页码：48-54
• 全文大小：1350 K

文摘

The effects of gamma ray irradiation on the shallow trench isolation (STI) leakage current in a 180 nm technology are investigated. The radiation response is strongly influenced by the bias modes, gate bias during irradiation, substrate bias during irradiation and operating substrate bias after irradiation. We found that the worst case occurs under the ON bias condition for the ON, OFF and PASS bias mode. A positive gate bias during irradiation significantly enhances the STI leakage current, indicating the electric field influence on the charge buildup process during radiation. Also, a negative substrate bias during irradiation enhances the STI leakage current. However a negative operating substrate bias effectively suppresses the STI leakage current, and can be used to eliminate the leakage current produced by the charge trapped in the deep STI oxide. Appropriate substrate bias should be introduced to alleviate the total ionizing dose (TID) response, and lead to acceptable threshold voltage shift and subthreshold hump effect. Depending on the simulation results, we believe that the electric field distribution in the STI oxide is the key parameter influencing bias effects on the radiation response of transistor.