Hello,
     Does anyone know of a way to completely remove K+ ions from the Si wafer
after anisotropic etching of silicon in KOH solution. Has anyone experimented
with washing the wafer throughly in ethanol/methanol ( 60 % : 40% v/v). I am
asking this question because, at IIT Bombay we have only one fabrication line
which is also used for CMOS processing. This has uptill now limited our process
sequence for MEMS devices in a way that all furnace processing has to be done
before KOH etch ( EDP etch was ruled out for our case <111>/<100> etch rate
ratio) so as to avoid contaminating the furnace which is also used for CMOS
processing.

If anybody know of a method to remove alkali metal ions, or has some reference
of left over K+ ions after a wash in MeOH/EtOH and subsequently in DI water,
please let me know at the earliest.

Thanking you all in advance.

Regards
Amit Shiwalkar