양방향 유체-구조 연성해석을 이용한 단일 밸브 진공 척의 내부 형상 최적화

Abstract

This paper proposes a method to solve the problem by optimizing the shape of the inside of the vacuum chuck in order to alleviate the wrinkling phenomenon of the film during the inspection of the flexible film using the ceramic vacuum chuck and shorten inspection time by using a one-valve type of a chuck. Flexible film is an important component in the display and semiconductor industries. Therefore, there is a need for a process of adsorption a flexible film with a vacuum chuck, attaching the flexible film to a ceramic porous plate, performing a flattening operation, and measuring the flatness and defects of the flexible film by optical measurement. Conventional ceramic vacuum chucks are used in single or multiple valve systems. The single valve type has advantages of easy control and short inspection time, but a strong suction pressure is generated where the valve is existed and the film is wrinkled. The multiple valve type can solve the wrinkling phenomenon of the film in the inspection time, but has a problem in that the productivity is deteriorated due to the delay of the inspection time due to the occurrence of tack time due to a large number of valve controls. In order to solve the problems in the single and multi-angle systems, there has been attempted to solve the problem by changing the internal channel of the vacuum chuck or attaching the suction sheet on the porous plate, but the above problems still occur and the productivity is deteriorated. In order to solve these problems, this paper proposed a technique to apply shape optimization inside vacuum chuck to make multi-valve vacuum chuck correspond to performance with fast inspection time using single valve. The proposed method simulates the suction process using a 2-way FSI for the flexible film considering the hyper-elastic properties with surround airflow and optimized the flow velocity profile on the porous plate and the inner shape of the vacuum chuck. In addition, a vacuum chuck with optimized internal shape has been developed and the adsorption process experiment of the actual film with the developed vacuum chuck has been conducted. From the experimental results, optimized vacuum chuck solves the wrinkling problem of the film, and the adsorption time was reduced by 66% than a conventional vacuum chuck with multiple valve system, and the error between the simulation and experimental results was within 2.5%. The proposed method and developed vacuum chuck are expected to have a great impact on the semiconductor and display industries and are expected to make a significant contribution to FSI and large deformation simulation research.