Thinning and polishing of cross-section of depth-graded WSi_2 /Si multilayer for linear zone plate application  

作　　者：黄秋实 朱京涛 李浩川 沈正祥 王晓强 王占山 唐永建 

机构地区：[1]Institute of Precision Optical Engineering, Physics Department, Tongji University [2]Shanghai Key Laboratory of Special Artif icial Microstructure Materials and Technology, Tongji University [3]Research Center of Laser Fusion, China Academy of Engineering Physics

出　　处：《Chinese Optics Letters》2012年第1期78-81,共4页中国光学快报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Nos.10825521 and10905042);the Natural Science Foundation of Shanghai (Nos.09XD1404000 and 09ZR1434300);the Project of International Cooperation (No.2008DFA01920)

摘　　要：A linear zone plate named multilayer laue lens （MLL） is fabricated using a depth-graded multilayer structure. The lens shows considerable potential in focusing an X-ray beam into a nanometer scale with high efficiency. In this letter, a depth-graded multilayer consisting of 324 alternating WSi2 and Si layers with a total thickness of 7.9μm is deposited based on the thickness sequence according to the demands of the zone plate law. Subsequently, the multilayer sample is sliced and thinned to an ideal depth along the cross-section direction using raw abrasives and diamond lapping. Finally, the cross-section is polished by a chemical mechanical polishing （CMP） technique to remove the damages and improve the surface smoothness. The final depth of the MLL is approximately 7 μm with an achieved aspect ratio greater than 400. Results of scanning electron microscopy （SEM） and atomic force microscopy （AFM） indicate that interfaces are sharp, and the multilayer structure remains undamaged after the thinning and polishing processes. The surface roughness achieved is 0.33 nm.A linear zone plate named multilayer laue lens （MLL） is fabricated using a depth-graded multilayer structure. The lens shows considerable potential in focusing an X-ray beam into a nanometer scale with high efficiency. In this letter, a depth-graded multilayer consisting of 324 alternating WSi2 and Si layers with a total thickness of 7.9μm is deposited based on the thickness sequence according to the demands of the zone plate law. Subsequently, the multilayer sample is sliced and thinned to an ideal depth along the cross-section direction using raw abrasives and diamond lapping. Finally, the cross-section is polished by a chemical mechanical polishing （CMP） technique to remove the damages and improve the surface smoothness. The final depth of the MLL is approximately 7 μm with an achieved aspect ratio greater than 400. Results of scanning electron microscopy （SEM） and atomic force microscopy （AFM） indicate that interfaces are sharp, and the multilayer structure remains undamaged after the thinning and polishing processes. The surface roughness achieved is 0.33 nm.

关 键 词：Aspect ratio Atomic force microscopy Chemical mechanical polishing POLISHING Scanning electron microscopy Silicon Surface roughness 

分 类 号：TN304.055[电子电信—物理电子学]