Al_2O_3界面钝化与热处理对Gd_2O_3-HfO_2高k薄膜电性能影响

Effect of Al_2O_3 Interfacial-Passivation and Anneal Process on Electrical Properties of Gd_2O_3-HfO_2 Films on Si Substrate

采用磁控溅射技术在p-Si(100)衬底上生长了Gd2O3掺杂HfO2(GDH)高k薄膜,制备了GDH/Si和GDH/Al2O3/Si两种堆栈层。结果表明Al2O3界面钝化使漏电流密度降低了两个数量级,并改善了回滞窗口和平带电压的偏移。高温N2退火对堆栈层电学性能影响明显:随着温度的增加,界面性能逐步改善,退火温度为900℃时,回滞窗口小于20 mV,积累区趋势平缓并且单位面积电容值增大,薄膜介电常数为20。

Effects of Al2O3 interfacial-passivation and anneal process on the electrical properties of Gd2O3-HfO2（GDH） high-k film were studied.Gd-doped HfO2 film was deposited on Si（100） substrate by radio frequency magnetron cosputtering.GDH/Si and GDH/Al2O3/Si stack were prepared with the same technique.The results showed that the leakage current density of the samples with Al2O3 interfacial passivation decreased two orders of magnitude,the bias of flat voltage and hysteresis obviously became better.The process of rapid thermal annealing at high temperature in N2 worked effectively.The quality of the interface increased with temperature arising,annealed at 900 ℃,negligible hysteresis（20 mV）,smoothing accumulation,and increasing unit-area capacitance（20） were acquired.