Curing Deformation Mechanism And Lens Shape Analysis Of Two Adhesive Structures

Integrated circuits were introduced in the 1950 s,which greatly reduced the size and cost of computers,and significantly improved computational efficiency.With the increasing progress of information technology in China,the demand for chip performance in industries such as the Internet,data computing,information transmission,manufacturing,and transportation systems is increasing.Considering the background of the current technological blockade imposed by various international forces on China,the research and development of domestically produced high-end chip manufacturing equipment in China is particularly important.The lens system is one of the core components of high-end lithography equipment,and its surface accuracy largely determines the manufacturing accuracy of chips.However,when the polymer in the adhesive structure used to fix the lens starts to shrinkage,it will generate additional loads on the lens,causing deformation of the lens,affecting the surface shape accuracy.This article will analyze the additional loads introduced during the curing process of two types of adhesive structures and their impact on the optical surface shape of lenses through the relevant theories of elasticity.Firstly,derive the stress-strain relationship of adhesive curing shrinkage through the theory of viscoelastic mechanics.In order to improve computational efficiency,a linear elastic simplification method for the adhesive material model was proposed to simplify the subsequent calculation process.The feasibility of this method was verified by comparing the surface shapes of the results by simulation and experiment.Secondly,the types and sizes of additional loads on the lens caused by the cantilever beam supported adhesive structure were analyzed,and the normal stress of the adhesive during curing shrinkage and the pressure on the lens surface caused by the surface of the elastic element head were calculated and the correctness of the results was verified through simulation software.In the calculation example,the lens deflections under real working conditions,and the condition of adhesive layer tension,and surface pressure of elastic components were calculated using simulation software,and Zernike fitting was performed.Optical surface evaluation indicators such as PV,RMS,and Zernike coefficient were introduced to evaluate the theoretical solution and simulation calculation of adhesive layer normal stress and lens optical surface under two working conditions.The comparison error between the two was less than 15%,confirming the effectiveness of the mechanical theoretical model.In addition,compare the optical surface error between 8-point adhesive structure and 16-point adhesive structure respectively in the calculation example.The results showed that as the number of support points increased,the surface error of the lens caused by the curing shrinkage of the adhesive layer would increase.Finally,the types and sizes of additional loads on the lens caused by the L-shape beam supported adhesive structure were analyzed,and the internal forces on the elastic component L-shape beam caused by the curing shrinkage of the adhesive layer were calculated.The accuracy of the results was verified using simulation software.In the calculation example,the horizontal axial force and bending moment on the L-shape beam were calculated through theoretical methods,and the error between the obtained results and the simulation was less than15%,confirming the accuracy of the calculation of the internal force on the L-shape beam(the load that the L-shape beam reacts on the lens).In addition,the deflection of the lens was calculated using simulation software for both the real working condition and the single action of the bending beam reaction force,and Zernike fitting was performed to evaluate the theoretical solution and the simulated optical surface shape of the lens under the two working conditions.The error of the main indicators of the two was less than 15%,confirming that the reaction force on the bending beam is the main factor causing the change of the lens surface shape due to the curing shrinkage of the adhesive layer.In addition,compare the optical surface error between 8-point adhesive structure and 16-point adhesive structure respectively in the calculation example.The results also show that as the number of support points increases,the surface error of the lens caused by the curing shrinkage of the adhesive layer would increase.The results of this article indicate that the tensile force on the lens caused by the contraction of the adhesive layer in the cantilever beam supported adhesive structure and the pressure on the lens caused by the head of the elastic element are the main factors affecting the surface shape accuracy of the lens.The main factor affecting the surface shape accuracy of the lens is the reaction force applied to the surface of the elastic element caused by the contraction of the adhesive layer in the curved beam supported adhesive structure.In addition,increasing the number of bonding points will further increase the impact of the two bonding structures on the optical surface shape of the lens.