Influence of Pretreatment on Silicon Surface Roughness in KOH Anisotropic Silicon Etching

Experimental research shows that different pretreatment methods make different effects on the surface roughness of the silicon wafer after the KOH etching.35℃ BOE,room temperature BOE,10:1HF and 50:1HF were used as etching solutions to make pretreatments on silicon wafers.The different KOH etching results were compared with the un-pretreatment etching ones under the same conditions.The experimental result shows the surface roughness of the silicon wafer with pretreatment is about 1nm thicker than that of the un-pretreatment one.The surface roughness of the silicon wafer which was pretreated in HF solution and then eteched with KOH becomes worse.