I see no issues working with piezoresistors at high frequencies, e.g. there is nothing inherent in a diffused silicon piezoresistor that would inhibit performance at frequencies that ULSI CMOS devices operate. You will of course need to monitor your RC constants and parasitics and design a mask layout and circuit with good noise immunity. --- T Zhuwrote: > Dear all: > > I am doing research on piezoresistive sensing > issues, specipiclly, for > the mechanical mixer applications, but in my > knowledge, up to date, the > piezoresistive approach is DC and for low frequency. > But i am target at > 20MHz, is that possible for piezoresistive sensing > approach? > > Anyone got some advice on that,or suggest some > literature for me? > > Thanks very much indeed. > > TT -- Raj Gupta, Ph.D. Volant Technologies San Francisco, CA http://terahz.org