Guy--
Simply put, electrons are needed at the surface for the etch reaction.
Heavily doped p-type silicon has a low electron concentration and etches
slowly.
Low-doped p-type and any doping of n-type will etch at the same rate, so use
either.
    --Kirt Williams    Senior Scientist    SAIC

----- Original Message -----
From: "Guy Haché" 
To: 
Sent: Friday, January 30, 2004 11:18 AM
Subject: [mems-talk] si etch with tmah, type N or P


> When using TMAH to etch Si, is it better to use type N or type P Si for a
high
> etch rate?
>
> Is it better heavily doped or lightly doped?
>
> Thank's