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/HfO
2
/Dy
2
O
3
/Al
2
O
3
/n-Si (100) tri-layer capacitors have been studied intensively. The HfO
2
/Dy
2
O
3
/Al
2
O
3
were fabricated by using both RF magnetron sputtering and E-beam evaporation techniques, respectively. The samples were annealed at 300
^o
C, 500
^o
C,700
^o
C, and 900
^o
C in N2 ambient for 40min. The device annealed at 700
^o
C 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 G
m
/ɷ-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