涂覆有热SiO2和SU-8膜的Si晶片中用白光反射光谱法（WLRS） 测量厚膜的厚度均匀性检测方案(白光干涉测厚)

Film Metrology SpecialistsFor further information please contact us at info@thetametrisis.com or sales@thetametrisis.comThetaMetrisis C 2015， www.thetametrisis.com ThetaMetrisis APPLICATION NOTE #015 Thickness uniformity measurement of Thick films by WhiteLight Reflectance Spectroscopy (WLRS) Goal： The accurate measurement of thickness and its uniformity of thick films on a reflectivesubstrate. Means & Methods： WLRS is introduced for the measurement of film thickness and uniformity in the case ofthick transparent films. All measurements were performed with an FR-Basic tuned to operate in the 400-1000nm spectral regime. The samples were Si wafers coated with thermal SiO2 and SU-8 films via spin coating.For the reference measurements a standard Si wafer was used. Results： Film thickness uniformity depends strongly on the film application method. Spin coating of viscoussolutions at low speed could produce film thickness non-uniformity while processes such as thermal oxidationor CVD lead to uniform films. In figs. 1-2 the film thickness measurements of a 3.0um thick SiOz are illustrated.Due to the thermal oxidation process the non-uniformity is zero (fig. 2). In figs. 3-6 the film thicknessmeasurements of thick spin-coated SU-8 films are presented. In the case of 10um SU-8， the non-uniformityover the probed area (~350um diameter) is 12nm (fig. 4)， considerably lower from the value for the 50um SU-8film， 131nm (fig.6)， because of the use of lower viscosity solution and application at higher speed. Figure 1： Experimental and Fitted reflectance spectra from ~3um SiO2 film without uniformity. Black： experimental，Red： fit. Figure 3： Experimental and Fitted reflectance spectra from a~10 um SU-8 film without non-uniformity. Figure 5. Experimental and Fitted reflectance spectra from the~50 um SU-8 film assuming zero non-uniformity. Figure 2： Experimental and Fitted reflectance spectra from a~3um SiO2 film. Zero non-uniformity is calculated. Figure 4： Experimental and Fitted reflectance spectra from a ~10um SU-8 film with non-uniformity. Figure 6. Experimental and Fitted reflectance spectra from the~50um SU-8 film. Non-uniformity is calculated with accuracy. 用白光反射光谱法（WLRS）测量厚膜的厚度均匀性目标：准确测量反射基材上厚膜的厚度及其均匀性。方法：WLRS被引入用于测量厚透明膜情况下的膜厚度和均匀性。 所有测量均使用FR-Basic进行，调谐后可在400-1000nm光谱范围内进行。 样品是通过旋涂涂覆有热SiO2和SU-8膜的Si晶片。 对于参考测量，使用标准的硅晶片。结果：膜厚均匀性在很大程度上取决于涂膜方法。 在低速下旋涂粘性溶液会产生膜厚不均匀，而诸如热氧化或CVD的过程会导致膜均匀。  图1-2示出了3.0μm厚的SiO 2的膜厚度测量。 由于热氧化过程，不均匀性为零。 给出了厚的旋涂SU-8膜的膜厚测量。 对于10μmSU-8，在探测区域（直径约350μm）上的不均匀度为12nm，远低于50μmSU-8膜的131nm的值， 因为使用了较低粘度的溶液并以较高的速度应用。结论：证明了膜厚度和膜厚度均匀性的准确测量FR的工具基于白光反射光谱(Reports) 。准确同步的厚度测量及薄膜的折射率-一个广泛的多样化的应用范围广泛的光电特性的工具和整体解决方案，如:半导体、有机电子、聚合物、涂料和涂料、光伏、生物传感、化学传感...