Wafering

  • Wafering process

Slicing

Slice ingot to pieces of as-cut wafers

As-cut Cleaning

Wash out glue,slury and dirt on wafer surface after slicing

Edge Grinding

Fine grind edge of wafer to remove edge mechanical stress

Lapping

Enhance wafer flatness

Post-lapping Cleaning

Wash out slury,metal dirt on wafer surface after lapping

Etching

Remove surface damage caused by lapping process

Resistivity Stabilizing

Remove thermal donor cause by oxygen clusters

Backside Gettering

Make good extrinsic gettering to trap metal on the back side of during thermal process at epi house/foundry

Backside Oxide Sealing

Prevent substrate dopant going from backside of wafer,which benefit resistivity uniformity at front side

Polishing

Make mirror-like surface ready for epi or device process

Pre-cleaning

Remove slurry and reduce metal/particle level on wafers surface

Geometry Chech

Inspect wafer geometry by automatic sorter

Appearance Inspection

Inspect wafer appearance by naked-eye and auxiliary light source

Final Cleaning

Reduce metal/particle level to meet customer request

Laser Scanning

Scan wafer surface by automatioc machine to ensure the particle and defect under certain level