Surface crystallization of amorphous fused silica during electron cyclotron resonance plasma etching
非晶熔石英表面等离子体刻蚀过程 中的表面晶化研究

After low pressure fluorine plasma ecthing and oxygen ion passivation,a crystallized layer composed of SiO2 nano-crystal grains is observed in an amorphous fused silica surface.The depth of crystallized layer is at least several hundreds nanometers.Fluorine and carbon ion are generated from Ar/CF4 by the method of electron cyclotron resonance（ECR）.F ion breaks Si-O band of initial silica surface layer and releases O ion.Carbon ion combines with oxygen ion,and turns into CO2,and SiF4 is generated from fluorine and silicon.After initial surface layer is removed,unsaturated Si atom remains.Si dangling bond recombines with new O ion and then creates crystallizedα-cristobalite nano-crystal grains under a high temperature.