类金刚石薄膜的紫外可见区光学特性研究

Optical Properties of the Diamond-like Carbon Films at the Ultraviolet and Visible Range

在类金刚石薄膜(DLC)光学特性的研究方面,主要工作集中在红外区光学特性,在可见区和紫外区光学特性研究方面存在空白;鉴于此详细研究了采用脉冲电弧沉积DLC薄膜在可见区和紫外区的光学特性。利用脉冲电弧离子镀技术,在石英基片上和不同工艺条件下制备了类金刚石薄膜,研究了类金刚石薄膜在紫外和可见区的光学常数、光学透过率和光学能隙。结果表明,主回路电压是薄膜的光学常数变化的主要影响因素,低主回路电压下制备的类金刚石薄膜具有较低消光系数和折射率;不同的工艺条件下制备的类金刚石折射率从2.56变化到1.89(波长400nm);沉积速率对薄膜的折射率和消光系数没有明显的影响;DLC薄膜的光学能隙在3.95 eV左右;紫外区和可见区的透过率谱和椭偏仪测得的光学常数相互一致。

Much effort have been made to research the DLC films＇ optical properties in inferred and less research of the DLC films＇ optical properties at ultraviolet and visible Range have been taken. So the details about the DLC films＇ optical properties in this range were studied. The refractive index, extinction index, optical gap and transmittance of the diamond-like carbon （DLC） films, prepared by pulsed arc Ion deposition on the silica substrate in different main-loop voltage （MLV） and pulsed frequency （PF）, were researched. The results show that the DLC films presented lower refractive index and extinction index with lower MLP, and no obvious effect of the deposition velocity on the optical constants could be observed. The refractive index showed large range variation from 2.56 to 1.89 at 400nm wavelength and the optical energy gap was determined to about 3.95eV. The measured transmittances were accordance to results of the optical constants from the ellipsometry.