【摘要】 设计并建立了一套基于光纤光谱仪的光学测试系统,将由电子束光刻技术制备的一组具有手征结构形貌的二维周期阵列结构作为样品,其由扫描电镜(SEM)测量得到的周期长度分别约为520、570及790nm。测试并研究了二维手征周期结构在白光垂直入射条件下光谱随衍射角的变化规律,以及将衍射光学方法用于复杂形貌的亚波长二维阵列的周期长度测量效果。结果表明,随着衍射角增加,所有样品的衍射波长均向长波偏移;在同一衍射角下,样品的衍射波长与其周期结构具有对应关系。利用正交光栅衍射方程,模拟了白光在垂直入射条件下的衍射光谱变化,以此推算样品的周期尺寸与SEM测得的数据相差小于3%,获得了良好的效果,表明了一般正交光栅衍射方程在复杂形貌结构中的适用性。更多还原

【Abstract】 An optical test system based on the optical fiber spectrum analyzer is designed and established.A series of two-dimensional periodic-arrays samples with chiral morphology are fabricated by electronbeam lithography technology.The periods of samples are measured by scanning electro microscope(SEM),which are 520nm,570nm,and 790nm respectively.On condition that the incident light is perpendicular to the surface of the sample,the change rule of the spectrum with diffraction angle under the white light is tested and analyzed firstly.Meanwhile,the measurement effect on the cycle length of complex morphology two-dimensional periodic-arrays is tested by diffraction optical method.The results indicate that the diffraction spectra of all samples will gradually move to long wavelength when the diffraction angle increases.And on the same diffraction angle,there is a relationship between the diffraction wavelength and the period length of the sample.Through the derived cross-grating diffraction equation,the diffraction spectral change of the sample under the normal incidence is simulated.The result is satisfied well,which indicates the applicability of cross-grating diffraction equation in complex morphology structure.Thus the period lengths of the samples are calculated,and we get that the deviation of the results from the observations of SEM is less than 3%.更多还原