Fig. 1. Pixel unit structure in 4T PPD type CMOS image sensor

Fig. 2. Flowchart of simulation

Fig. 3. Doping distribution of pixel units in 4T PPT type CMOS image sensor

Fig. 4. Schematic of influence mechanism of charge transfer. (a) TG open; (b) TG shut down

Fig. 5. Driving timing in CTI theoretical simulation

Fig. 6. Electron concentration distribution of photogenerated charge in process of formation and transfer. (a) PPD is fully depleted before illumination; (b) photogenerated charge is collected in PPD after illumination; (c) photogenerated charge in PPD is transferred to FD when TG is turned on; (d) residual photogenerated charge in PPD after TG is turned off; (e) accumulated charge in PPD under dark field; (f) residual photogenerated charge in PPD is transferred to FD when TG is turned on

Fig. 7. Distribution of carriers captured by displacement damage defects after irradiation with different neutron injection amounts. (a) 0; (b) 1×10¹¹ neutron/cm²; (c) 5×10¹¹ neutron/cm²; (d) 1×10¹² neutron/cm²

Fig. 8. Variation curves of displacement damage defect filling rate with neutron irradiation fluence

Fig. 9. Variation curves of electron concentration in PPD with neutron irradiation fluence

Fig. 10. Test picture of CMOS image sensor

Fig. 11. Variation curve of CTI with neutron irradiation fluence

Table 1. Defect information in Si substrate after neutron irradiation with energy of 1 MeV^[15]

Table 2. Degradation of charge transfer loss with neutron fluence