Commandré M, Pelletier E
Appl Opt. 1990 Oct 1;29(28):4276-83. doi: 10.1364/AO.29.004276.
We review the principle of photothermal deflection for measuring absorption losses in TiO(2)films. A collinear arrangement gives the best sensitivity for the detection of losses in a low absorbing film deposited on a transparent substrate. The nineteen TiO(2) films produced by six different processes (electron beam evaporation, ion assisted deposition, ion beam sputtering, ion plating, ...), discussed at the 1986 Optical Society of America annual meeting, are measured by this technique. The extinction coefficients of the different films do not show obvious correlation with the deposition method. An important fact is that we have detected a variation in absorption as a function of time on some layers. This absorption shift is connected with the illumination conditions of the sample under study (wavelength: 600 nm; incident power: 400 W/cm(2)). Experimental results over time are given. The evolution of the photothermal signal is different from one sample to another. This phenomenon is partially reversible and depends on moisture degree of atmosphere.
我们回顾了用于测量TiO₂薄膜吸收损耗的光热偏转原理。对于检测沉积在透明衬底上的低吸收薄膜中的损耗，共线配置具有最佳灵敏度。通过该技术测量了在1986年美国光学学会年会上讨论的由六种不同工艺（电子束蒸发、离子辅助沉积、离子束溅射、离子镀等）制备的19种TiO₂薄膜。不同薄膜的消光系数与沉积方法没有明显的相关性。一个重要的事实是，我们在某些层上检测到了吸收随时间的变化。这种吸收偏移与所研究样品的光照条件（波长：600 nm；入射功率：400 W/cm²）有关。给出了随时间的实验结果。光热信号的演变因样品而异。这种现象部分是可逆的，并且取决于大气的湿度。
