When we contact silicon with spreading resistance probe tip (at about a
million pounds per square inch) we get a considerably lower resistance with
p-type than with n-type of the same resistivity.  That seems to fit the
pattern under discussion.

Roger Brennan

-----Original Message-----
From: Guillermo Villanueva
Sent: Thursday, November 10, 2005 9:09 AM
To: General MEMS discussion
Subject: Re: [mems-talk] p-type or n-type piezoresistances?

It's easier to achieve higher pi factors with p-type and standard silicon
wafers.