椭圆偏振研究溅射气压对锰膜光学性质的影响

Influence of sputtering pressures on the optical properties of manganese film based on spectroscopic ellipsometry

采用射频磁控溅射技术在Si(111)基片上制备金属锰膜,用椭圆偏振光谱在2.0~4.0 e V光子能量范围内研究了溅射压强对锰膜光学性质的影响.分别用德鲁得-洛伦兹模型以及有效介质模型对椭偏参数进行拟合,结果表明随压强增大薄膜致密度先增大后减少;折射率随压强增大先减少后增大;而消光系数随压强的变化与光子能量有关,在低能量区变化复杂,高能量区随压强增加与折射率规律一致.分析表明上述变化与薄膜的致密度密切相关.

Spectroscopic ellipsometry was used to investigate the optical properties of M n film deposited with different sputtering pressures on silicon substrates in the photo energy range of 2. 0 ~ 4. 0 e V. Parameterized analyses,based on Drude-Lorenz model and Bruggeman effective-medium approximation model,were used to fitting the elliptic parameters.The results imply that the density of M n films first increases and then decreases with increasing of Ar pressure,whereas the refractive index changes with Ar pressure in a contrary way. M eanwhile,the extinction coefficient has a complex relationship with Ar pressure at lower photo energy,the extinction coefficient changes in line with the refractive index when photo energy exceeds 2. 8 e V. M oreover,the effects of Ar pressure on optical constant of the film depend strongly on the variation of the M n atomic density.