负离子元素杂质破坏模型

Negative-ion element impurities breakdown model

探讨了HfO_2薄膜中负离子元素杂质破坏模型,并得出薄膜中的杂质主要来源于镀膜材料.用电子束蒸发方法沉积两种不同Cl元素含量的HfO_2薄膜,测定薄膜弱吸收和损伤阈值来验证负离子元素破坏模型.结果表明,随着Cl元素含量的增加薄膜的弱吸收增加损伤阈值减小.这主要是因为负离子元素在蒸发过程中形成挥发性的气源中心而产生缺陷,缺陷在激光辐照过程中又形成吸收中心.因此负离子元素的存在将加速薄膜的破坏.

Negative-ion element impurities breakdown model of HfO2 optical thin film is reported. We believe the main impurity element in thin film comes from the coating material. The weak absorption and laser induced damage threshold （LIDT） of HfO2 thin film are measured to testify the negative-ion element impurities breakdown model. These results indicate that the LIDT would decrease and the absorption of the films would increase with the increase of the content of negative-ion element. The main reason is the negative-ion elements become the center of volatile gas source and form defects, which in turn become the center of absorption during laser irradiation. So negative-ion elements are harmful impurities, their existence will speed up the damage of the thin film.