Nuclear Techniques ›› 2019, Vol. 42 ›› Issue (7): 0-070203-6.

• ACCELERATOR, RAY TECHNOLOGY AND APPLICATIONS •

### Effect of secondary electron non-equilibrium on the absorbed doses of CMOS device sensitive area and total ionizing dose effect

Yuankun WANG,Qian WANG(),Tao WANG,Jing LIU

1. School of Physics and Technology, Xinjiang University, Urumqi 830046, China
• Received:2019-04-11 Revised:2019-04-23 Online:2019-07-10 Published:2019-07-16
• Contact: Qian WANG E-mail:wq@xju.edu.cn
• About author:WANG Yuankun, male, born in 1992, graduated from Hankou University in 2015, master student, focusing on radiation dosimetry
• Supported by:
Supported by National Natural Science Foundation of China(No.11765022)

Abstract: Background

Absorbed dose is the most important physical quantity in the study of radiation effect. In the total ionizing dose experiment of 60Co gamma ray, the secondary electron equilibrium condition is not satisfied in the sensitive area of a thinner device. The actual absorbed dose could be less than the irradiation dose measured by the same dosimeter.

Purpose

This study aims to analyze and evaluate the influence extent of secondary electron imbalance on the absorbed dose and total ionizing dose of the sensitive layer of the device.

Methods

By studying the total ionizing dose effect with 60Co γ-rays on complementary metal oxide semiconductor (CMOS) device “CC4069 inverters", the difference between the absorbed doses of the sensitive layer of CC4069 inverters and the nominal irradiation dose measured by the dosimeter was calculated by Monte Carlo simulation. Combined with the measurement of the threshold voltage of the irradiation sensitive parameter of CC4069 inverter, the relationship between the threshold voltage drift of positive channel metal oxide semiconductor (PMOS) and negative channel metal oxide semiconductor (NMOS) under different bias conditions and the nominal irradiation dose and absorbed dose corrected by Monte Carlo simulation were analyzed and compared.

Results

The results show that the absorbed dose of the device sensitive layer is only 83.52% of the nominal irradiation dose.

Conclusion

The radiation test under the condition of secondary electron non-equilibrium will affect the evaluation of radiation hardening of device, and the radiation hardening of the device is overestimated by 16.5%.

CLC Number:

• TL72