Development Of Self-regressive Fixed Abrasive Polishing Pad

With the rapid development of information technology,semiconductor materials have been widely used in consumer electronics,photovoltaic lighting systems,communication systems,medical instruments,new energy and other fields.The semiconductor revolution is constantly advancing,from the first generation of semiconductor Si to commercial performance.The stable third-generation sapphire(Al₂O₃)and silicon carbide(Si C)materials all convey the information of the rapid development of the times.Chemical mechanical polishing(CMP)technology is one of the most practical and effective technologies to achieve global planarization of the substrate material surface.At present,the traditional processing method is free abrasive chemical mechanical grinding and polishing.There is a cost of consumables in processing using traditional chemical mechanical polishing technology,waste liquid treatment is harmful to the environment and other shortcomings.The development of the fixed abrasive chemical mechanical polishing(FA-CMP)technology comes from the traditional CMP technology.The planarization technology is expected to replace the traditional chemical mechanical polishing technology due to its strong process controllability,low processing cost,environmental protection and harmlessness.However,both the free abrasive and the fixed abrasive polishing technology have defects such as inconsistent surface scratches after processing.This article puts forward the subject of self-regressive fixed abrasive polishing pad,which provides theoretical and technical reference for workpieces in the direction of chemical mechanical polishing of fixed abrasives.The main research contents are as follows:(1)The effect of curing method on the performance of self-regressive fixed abrasive polishing padThe effects of three curing methods on the preparation performance of the self-regressive fixed abrasive polishing pad were studied.The hardness,structure,and wetting properties of the polishing pad were compared,and the performance was analyzed by single factor tests.The results showed that:hot pressing and the hot pressing and light curing method is difficult to control the temperature and the molding time is long;while the light curing method is convenient and efficient in molding,has good environmental performance,and is easy to realize enterprise production.Finally,the photo-curing method is selected as the polishing pad preparation and molding method.(2)Research on the composition of self-regressive fixed abrasive polishing padUsing swelling rate and Young's modulus as performance evaluation indexes of self-regressive fixed abrasive polishing pad,through orthogonal experiment and comprehensive balance method,the significant influence of resin and active agent on swelling rate and young's modulus was studied.Determine the composition of the self-regressive fixed abrasive polishing pad.The results show that:the light-curable resin has a more significant effect on the swelling rate than water-based polyurethane,and the Young's modulus has the same effect;polishing pad composition:UV resin is 23 ml,Water-based polyurethane resin is 35 ml,trimethylolpropane triacrylate(TMPTA)is 2 ml,polyethylene glycol diacrylate(PEGDA)is 2 ml,photoinitiator(UV1173D)is 3 ml,dispersant(YKC590)is 1.5 ml.(3)Study on the curing process of self-regressive fixed abrasive polishing padThe curing process of the polishing pad was explored through orthogonal experiments using a built-up curing device.The results showed that the curing process of the polishing pad was the best when the curing time was 180 s,the curing distance was 180mm,and the abrasive content was 3 g.The single factor test method was adopted,and the swelling rate,young's modulus and friction coefficient were used as indicators for the curing process of self-regressive fixed abrasive polishing pad.The results showed that:under the same test conditions,the swelling rate,polyurethane polishing pad is smaller than layered curing Polishing pad and smaller than direct curing polishing pad,direct Young's modulus:connecting curing polishing pad is smaller than polyurethane polishing pad and smaller than layered curing polishing pad,select the layered curing process according to the swelling rate,Young's modulus and the stability of the friction coefficient.(4)Study the relationship between the processing performance of the polishing pad and the performance of the workpiece,starting from the particle size,verify the processing performance of the polishing pad,and test the retreat performance of the polishing pad.Through single factor tests,it is found that:the surface porosity of the polyurethane polishing pad is 65%,the surface porosity of the self-regressive fixed abrasive polishing pad is 44%.The surface roughness of the polyurethane polishing pad is twice that of self-regressive fixed abrasive polishing pad.The average particle size changes after the abrasive wears 0.023 mm,the change in grain distance is 0.04 mm,and the measured retreat range of abrasive grains in the polishing pad is 0-20?m.Comparing the test results of Si C wafers and 304 stainless steel wafers after polishing,it can be seen that the self-regressive fixed abrasive polishing pad are more suitable for reducing or reducing the surface scratches of materials.