Investigation of annealing temperature and gamma irradiation on HfO2/Dy2O3/Al2O3/n-Si (100) memory capacitor

The effect of annealing temperature and gamma irradiation on Al/HfO2/Dy2O3/Al2O3/n-Si (100) tri-layer capacitors have been studied intensively. The HfO2/Dy2O3/Al2O3 were fabricated by using both RF magnetron sputtering and E-beam evaporation techniques, respectively. The samples were annealed at 300oC, 500oC,700oC, and 900oC in N2 ambient for 40min. The device annealed at 700oC had a large memory window of 8.22V under sweeping voltage ±12V compared to other annealed devices. This is attributed to the excellent charge storage capability of the device. Thereafter, this device was exposed to gamma irradiation at various doses of 4 Gy to 16 Gy. C-V and Gm/-V measurements were performed before and after irradiation at 1MHz. The C-V curves shifted toward the positive voltage side. This could be related to the oxide-trapped and interface-trapped charges generated during irradiation © 2023 IEEE.