氮气含量对硅基AlN薄膜结构及性能的影响

Structure of AlN thin films on Si substrate with different N_2 pressure

研究了直流磁控溅射法沉积AlN薄膜过程中氮气含量对AlN薄膜结构及性能的影响.实验结果表明:当真空腔的氩气含量较低时,薄膜呈非晶态,在红外波段的傅里叶变换光谱中没有明显的吸收峰,当氮气流量为75%时薄膜中出现明显的六方AlN(100)和AlN(110)衍射峰,在波数为670～700cm-1处有强烈的吸收峰;增加氮气含量,薄膜又呈现出非晶状态.薄膜的表面粗糙度和颗粒大小都随氮气含量的增加先增大后减小..

Polycrystalline hexagonal A1N thin films were prepared by DC magnetron reactive sput- tering on p-Si（111） substrates with different N2 pressure. The experimental results showed that when the N2 pressure in the vacuum chamber was lower, the A1N thin films were amorphous and there was no absorption in the Fourier transformation infrared spectra; when the Nz concentration in the vacuum chamber was 75%, the thin films were polycrystalline hexagonal A1N（100） and A1N（110）, and an in- tense absorption emerged at 670-700 cm-1 in the Fourier transformation infrared spectra; when the N2 pressure increased further, the A1N thin films were again amorphous; with increasing Nz pressure, the surface roughness and average grain diameter of the thin films increased firstly, and then decreased.