Hello,

   I am looking for vendors of high quality, defect free, 4" Si wafers
for KOH etching.  I am currently using CZ wafers oriented to <100>+/-
0.1 degrees, 525um+/- 0.25 um thick and a primary flat oriented to <110>
+/- 0.25 degrees.  The wafers work well most of the time, but
occasionally I encounter yield problems due to crystal defects.  I am
looking to evaluate other wafer vendors and would like any
comment/suggestions on high quality suppliers.  Also, what is your
preference (CZ vs. FZ) for KOH etching?

Thanks

John Fijol