Hi, Moshe:
what solution  u r using to do the wet etching and what's the concentration? u
need to give us more details about ur etching condition. Normally, 35%w KOH
solution at around 70C can do a good job. Generally speaking, lower etching
speed will give u smoother surface.

guocheng shao

Moshe  wrote: > Hello
> When I operate wet etch to thin silicon wafer I get like
> scratches on the surface.
> I am locking for technique to get smooth surface on the silicon
> wafer when I operate thinning by wet etch .
> The wafer is without any mask.
> Thank You