Research, design and experiment of end effector for wafer transfer robot

Purpose - Wafer transfer robots play a significant role in IC manufacturing industry and the end effector is an important component of the robots. The purpose of this paper is to improve transfer efficiency of a wafer transfer robot through study of its end effector, and at the same time to reduce wafer deformation. Design/methodology/approach - Finite element method is adopted to analyze wafer deformation. For wafer transfer robot working in vacuum, for the first time, the authors apply the research of microfiber arrays inspired by gecko to the design of robot's end effector, and present equations between robot's transit acceleration and parameters of microfiber arrays. Based on these studies, a kind of micro-array bump is designed and fixed to a structure optimized end effector. For wafer transfer robot working in atmospheric environment, the authors have analyzed the effects of different factors on wafer deformation. The pressure distributions in absorption area and calculation formula of maximal transfer acceleration are put forward. Finally, a new kind of end effector for atmospheric robot is designed according to these studies. Findings - The experiments results show that transfer efficiency of wafer transfer robot has been significantly improved through application of the research in this paper. Also wafer deformation under absorption force has been controlled. Practical implications - Through experiments it can be seen that the research in this paper can be used to improve robot transfer ability and decrease wafer deformation in the production environment. Also the studies of end effector lay a solid foundation for further improvement. Originality/value - This is the first application of the research of gecko-inspired microfiber arrays to vacuum wafer transfer robot. This paper also carefully analyzes effects of different factors on wafer deformation through finite element method.