A facile and scalable fabrication method of highly periodic array of nano-sized voids with large area (182 cm ) has been achieved by means of a template related 3-step procedure. A non-close packed (NCP) colloidal SiO2 array was fabricated by programmed spin-coating and in situ polymerization. The colloidal SiO2 arrays are embedded in a polymer matrix, and the spheres of the top layer protrude out of the film, forming a periodic surface. After being etched by HF aqueous solution, the first layer of SiO2 microspheres in the template were etched off and left behind a highly periodic hexagonal array of polymer nanovoids. The periodicity of the resulting polymer nanovoids array is the same as that of colloidal SiO2 arrays. The volume of nanovoid is as small as about 4.72 attoliter per void, and the density of voids can be as high as about 4.9 × 108 voids/cm . The metallic nanovoids array could be fabricated by subsequent deposition of Cr and Au layers. The resulting array of metallic nanovoids could be used as surface-enhanced Raman scattering (SERS) active substrates with ultra-sensitivity and excellent reproducibility. The SERS performance of our nanovoids array was probed by benzenethoil. The SERS enhancement factor (EF) can be as high as in the order of 108~109 on average over 182 cm2. The mean relative standard deviation (RSD) of EF is in the range of 5.5% to 8.6% over 182 cm2 which indicates the reproducibility of the substrates is quite good. The methodology leverages the high uniformity of the spin-coated colloidal arrays and well-established physical vapor deposition techniques. The formation of nanovoids array with high periodicity over large areas could lead to important technological applications in nanoelectronics and sensors.%以内嵌在聚合物内、呈周期性非紧密接触方式排布的SiO2微球阵列聚合物复合薄膜为模板,采用HF选择性地蚀除复合薄膜表层SiO2微球后,便可便捷地得到单片面积达182 cm2、呈等边六边形周期性排布的有机球凹阵列,每个微球凹的容积约为4.72阿升(Attoliter,1 Attoliter=10-18 L),球凹排布密度约为4.9×108球凹/cm2;镀金后的球凹阵列可用作SERS活性基底,以苯硫酚为探针的SERS结果表明,球凹阵列的Raman信号增强因子(EF)高达108～109量级,在182 cm2范围内EF的RSD值在5.5％～8.6％范围内.
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