Dear Sir/Madam,

Do you know how to make via holes - i.e. holes through
a quartz glass (fused silica) 4 " wafer, 525 microns thick?

Or do you know anybody else who can do this (in Europe if possible?)
by laser or ultrasonic drilling? Or any other technique?

I need to have approx. 160 holes in each wafer.
The wafer is covered with photoresist (or other masking material)
to mark the location of the through holes,  but also to protect
the bonding surface on the other side from mechanical scratch ...
The hole location is quite important...

I'll  be happy to hear from you soon !

Thanks!

Best regards