Thin hafnium oxide films were prepared by atomic layer deposition using a carbon-free precursor, tetrakis(tetrahydroborato)hafnium [Hf(BH₄)₄], and H₂O. Film growth was studied using an in situ quartz crystal microbalance and Fourier transform infrared spectroscopy measurements. Self-limiting growth was observed between 100 and 175 °C, but the thermal decomposition of the Hf precursor occurred at higher temperatures. The film properties were investigated using x-ray photoelectron spectroscopy, x-ray reflectivity, x-ray diffraction, ellipsometry, time-of-flight secondary ion mass spectrometry, and x-ray absorption spectroscopy. The as-deposited films were found to consist of an amorphous mixture of HfO₂ and B₂O₃, and had a lower density and lower refractive index compared to pure HfO₂ thin films. Annealing the films to >750 °C yielded crystalline monoclinic HfO₂ with a density of 9 g/cm³ and a refractive index of 2.10.

中文翻译：

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使用无碳四（四氢硼酸）ha和水的HfO2膜原子层沉积

使用无碳前驱体，四（四氢硼酸根）[[Hf（BH ₄）₄ ]和H ₂ O ，通过原子层沉积制备氧化ha薄膜。使用原位石英晶体微天平和傅里叶变换研究膜的生长。红外光谱测量。在100至175°C之间观察到自限生长，但Hf前体的热分解发生在较高温度下。使用X射线光电子能谱，X射线反射率，X射线衍射，椭圆光度法，飞行时间二次离子质谱法和X射线吸收光谱法研究膜的性质。发现沉积的薄膜由HfO ₂和B的无定形混合物组成₂ O ₃，与纯HfO ₂薄膜相比，密度和折射率较低。将膜退火至＞ 750℃，得到结晶的单斜晶HfO ₂，其密度为9g / cm ³，折射率为2.10。