Ce掺杂HfO2薄膜的化学溶液法制备及其铁电性能研究

Preparation and Ferroelectric Properties of Cerium Doped HfO2 Thin Films by Chemical Solution Method

氧化铪基薄膜与金属氧化物半导体(CMOS)工艺高度兼容,具有良好的可微缩性和保持性能,其铁电性的发现引起了科学家们的广泛关注.该文通过化学溶液法在铂(Pt)衬底上制备5mol%和10mol%的铈掺杂氧化铪基(Ce:HfO2)薄膜,并在不同的退火温度条件下对薄膜进行处理.分别利用电滞回线,掠入射X射线衍射(GIXRD)对薄膜的铁电性能和结构进行了测试和表征.研究发现:5mol%的铈掺杂氧化铪薄膜具有铁电性,铈掺杂在氧化铪中诱导了铁电正交相;10mol%的铈掺杂氧化铪薄膜则表现出了反铁电性,最大剩余极化(Pr)为21.02μC/cm^2.实验结果表明,通过调控掺杂浓度,铈元素能诱导出氧化铪薄膜中的铁电相.

The discovery of ferroelectricityin hafnium oxide (HfO2) thin film has attracted widespread attention from scientists, due to the complementary metal-oxide-semiconductor (CMOS) highly compatibility, sufficient scalability and satisfactory retention properties of HfO2 based thin films. In this work, HfO2 thin films with different cerium doping contents (5 mol% and 10 mol%) were fabricated by chemical solution method, and the films were treated under different annealing temperature. The ferroelectric properties were characterized by polarization-voltage (P-V) hysteresis loops while the structural properties were investigated by grazing incidence X-ray diffraction (GIXRD). It is found that 5 mol% Ce doped HfO2 thin film exhibited ferroelectricity, while 10 mol% Ce doped HfO2 thin film showed antiferroelctricity, with a maximum remanent polarization (Pr) of 21.02 μC/cm^2 . These results indicate that Ce doing with appropriate content could effectively induce ferroelectricity in HfO 2 thin films.