Influence of XeCl excimer laser annealing on the ferroelectric nondoped HfO2 formation deposited on Si(100) substrate

Abstract

In this research, we have investigated the effect of excimer laser annealing (ELA) on the ferroelectric nondoped HfO2 (FeND-HfO2) formation deposited on Si(100) substrate. The XeCl (λ: 308 nm) ELA was irradiated as post-deposition annealing (PDA) in the N2 ambient to the 10 nm thick HfO2 deposited by RF-magnetron sputtering without substrate heating. The C-V characteristics of Al/HfO2/p-Si(100) metal/ferroelectrics/Si (MFS) diodes were gradually improved with the energy density of ELS from 170 mJ/cm2 to 270 mJ/cm2 irradiated at 200 Hz for 200 shots although charge-injection type hysteresis of 0.2-0.3 V was remained. The post-metallization annealing (PMA) at 400oC/5 min in N2/4.9%H2 ambient for Al/HfO2/p-Si(100) MFS diodes markedly improved the C-V characteristics, and negligible hysteresis with ideal flat-band voltage (VFB) was realized. The memory window (MW) of 0.42 V was achieved by the program/erase (P/E) operation with the input pulses of +3 V/100 ms and -8 V/100 ms for the MFS diode with ELA energy density of 270 mJ/cm2 at 200 Hz for 200 shots followed by the PMA..