Sputtered Pyrex films being so thin can breakdown more easily at high voltages
than thicker substrates. I have use 3.5 MV/m as a safe limit to calculate the
voltage for anodic bonding. In this case 7 volts should be sufficient for your
application, or a greatly reduced voltage versus 120V. I have also found that
such thin films do not require much heating. I would suggest performing the
bond at temperatures closer to 100*C than 350*C. You can try this on silicon
substrates and use IR to inspect bond interface to set up your process.
Loren St. Clair