Research On Physical And Chemical Properties Of Chemical Modified Solution For Chemical Mechanical Micro-grinding

Monocrystalline silicon is a hard and brittle material commonly used in high-performance parts applications such as photovoltaic industry,aerospace and aerospace,etc.It is characterized by good chemical stability,high hardness,high brittleness,good wear resistance,and excellent chemical mechanical properties.In the three-dimensional micro-structured micro-grinding process of monocrystalline silicon,it is easy to generate edge defects such as edge cracks,chipping,and missing corners,thereby affecting its performance.In order to realize the few defects,even defect-free,high-quality and high-efficiency processing of the three-dimensional structure of hard and brittle material micro-components,this thesis introduces the chemical modification effect of chemical-mechanical processing technology into micro-grinding processing,focusing on research chemical modification mechanism.The chemical reaction conditions for the chemical modification of the monocrystalline silicon material are analyzed.And the physicochemical properties of the chemical modification solution are analyzed.The reaction condition parameters of the chemical modi fication solution are optimized.The chemical modification mechanism of the chemical modification solution to the monocrystalline silicon material is discussed.The details are as follows.Research on chemical modification mechanism of monocrystalline silicon.Taking the?100?crystal plane monocrystalline silicon as the res earch object,based on the material properties analysis,the chemical modification solution compositions are selected.The principle of the chemical modification of monocrystalline silicon induced by the energy input is analyzed.The chemical modification experiments are designed and the monocrystalline silicon chemical modification solution physical and chemical properties analysis tests are introduced.Research on chemical properties of monocrystalline silicon chemical modified solution.The single factor experiment of the monocrystalline chemical modification based on the changes of alkali concentration,pH value,reaction temperature and solution composition in the chemical modification solution is designed.The influence of various factors on the chemical modification degree of the monocrystalline silicon material is analyzed.Based on inductively coupled plasma mass spectrometry?ICP?detection,the content of Si in the modified solution is detected.And based on infrared spectroscopy detection,the change of the composition after the modification reaction is analyzed.As the alkali concentration increases,the Si content in the chemically modified solution increases.As the reaction temperature increases,the more Si element content is detected in the solution after chemical modification.When the pH value of the solution increase,the Si element content in the solution after chemical modification will be higher concentration.With the increase of the amount of components added in the chemical modification solution,the content of Si in the chemical modification solution increases first and then decreases.Based on results of single-factor experiments,four factors and three levels of orthogonal test is further designed.The influence of various factors on the chemical modification of monocrystalline silicon is discussed based on the changes in the content of Si in the chemical modification solution was discussed.Then the pH value of chemical modification solution,reaction temperature and chemical composition and other chemical modification conditions are optimized.In order to simulate mechanical stress modification conditions,reciprocating friction and wear experiment is designed to reveal the chemically modified thermo-mechanical reaction conditions for the chemo-mechanical micro-grinding of monocrystalline silicon materials.The ICP is used to test the chemical modification solution medium in the friction and wear test.The results showed that mechanical stress could promote the chemical modification of monocrystalline silicon.Research on mechanical properties of monocrystalline silicon chemically modified layers.The nano-indentation experiment of the chemically modified monocrystalline silicon layer is designed to analyze the variation of nano-hardness and elastic modulus of chemically modified monocrystalline silicon layers under different chemical modification conditions.The nano-indentation morphology of samples is observed by atomic force microscopy.Different chemical modification conditions lead to varying degrees of nano-hardness and elastic modulus of chemically modified monocrystalline silicon layer.When the pH value of the solution means 10,modification temperature means 160°C;and the ratio of H₂O₂ and EDTA-Fe-Na is close to 1:1,the nano-hardness and elastic modulus of chemically modified monocrystalline silicon layer are the minimum compared with other samples.The chemical modification layer scratch test of monocrystalline silicon is futher carried to analyze the effect of different chemical modification conditions on the removal characteristics of monocrystalline silicon material.Research results show that the nano-hardness and elastic modulus of the chemical modification layer of monocrystalline silicon decrease under chemical modification condition.And the brittle-plastic zone processing transformation will been achieved under controlled method.For the future to solve the processing defect problems in the monocrystalline silicon three-dimensional microstructure,a feasible micro-griding method is proposed.The research results provide theoretical and experimental support for futher study on chemo-mechanical miro-griding.