Surface Damage Formation Mechanism Of Ultra-precision Grinding Of Monocrystalline Gallium Oxide

Single crystal gallium oxide has the advantages of ultra-wide band gap,low energy loss,high thermal stability and chemical stability,etc.It is used to manufacture high-temperature,high-frequency and high-power microelectronic devices,solar-blind ultraviolet photodetectors,and ultraviolet transparent conductive electrodes.Preference is given to semiconductor materials.However,single crystal gallium oxide has high hardness,high brittleness,and anisotropy.It is easy to cleavage and break during processing,which is a typical difficult-to-process material.Ultra-precision grinding processing has the advantages of good surface layer quality,high precision,low cost and high efficiency,and is increasingly applied to the processing of hard,brittle and difficult materials.However,in the single crystal gallium oxide grinding process,a certain degree of damage will be produced on the surface layer,which will affect the quality of the finished product.Therefore,this paper studies the formation mechanism of single crystal gallium oxide ultra-precision grinding surface damage and low-damage grinding process.Through the grinding of single crystal gallium oxide with different particle size diamond wheels,the impact of the grinding wheel particle size on the surface layer damage of single crystal gallium oxide is analyzed.,To study the formation mechanism of single crystal gallium oxide ultra-precision grinding surface damage;then,the surface layer damage depth prediction model was established and tested and verified;finally,the single crystal gallium oxide low-damage ultra-precision grinding process was proposed.The research results are of great significance to low-damage ultra-precision grinding,optimizing the grinding process and improving the quality of finished products.The main research content and results of this paper are as follows:(1)Through the ultra-precision grinding test,the damage mechanism of the single crystal gallium oxide grinding surface layer is determined.The material removal method of single crystal gallium oxide is brittle fracture removal and plastic removal;the damage form of different material removal methods is analyzed,the brittle area grinding The surface damage form of single crystal gallium oxide grinding is microcracks,pits,and deep wear marks;the surface damage form of single crystal gallium oxide grinding in plastic domain is fine wear marks;among them,#600 and #1500 diamond wheels are used for single crystal grinding.The material removal method for gallium oxide is brittle fracture removal,and the material removal method for single crystal gallium oxide grinding with #2000 and #5000 diamond wheels is plastic removal;as the size of the grinding wheel particles continues to decrease,single crystal gallium oxide grinding The quality of the surface layer becomes better,and the damage depth and surface roughness of the single crystal gallium oxide surface layer are reduced accordingly.(2)A prediction model of the damage depth of the surface layer of the workpiece rotation method was established.According to the relationship between the depth of cut of abrasive grains and surface roughness,the depth of cut of abrasive grains and the depth of surface layer damage,a prediction model of surface roughness(Ra)and surface layer damage depth was established.In the process of model building,the geometric parameters of the machined surface profile,the different action modes of brittle and ductile material removal,and the indentation fracture mechanics were considered,and the accuracy of the model was verified by the variable parameter grinding test.(3)Based on the analysis of the damage mechanism of single crystal gallium oxide grinding surface layer and the prediction model of surface layer damage depth,and with the main goal of improving the processing efficiency of single crystal gallium oxide and reducing surface layer damage,a low-damage ultra-precision grinding process is proposed.Process,rough grinding adopts #1500 diamond wheel and fine grinding adopts #5000 diamond wheel.The grinding verification test was carried out on the proposed process,and a smooth and low-damage monocrystalline gallium oxide surface layer was obtained,thereby realizing the low-damage ultra-precision grinding of monocrystalline gallium oxide.