An idea:

Shoot 2 alignment mark masks. Attach them to each other along one
edge with a spring/hinge fixture, after carefully aligning the 2
alignment masks to each other. The hinge/spring should allow the
masks to be parted and a wafer (with photoresist spun on both sides)
inserted in between. Expose each side in turn and develop. Etch the
marks into both sides and align subsequent layers normally. We have
gotten better than 10 micrometers front to back with this method. The
hinge/spring was a bent piece of stainless shim stock which was
epoxied to the masks after aligning them in a standard front side
mask aligner.

Jim


On Jul 2, 2006, at 1:46 PM, Andrea Mazzolari wrote:

> Hi all, I have a single sided mask aligner and i need to make a
> photolithography with front anb back aligned.
> I'm looking for informations (articles or books) which describe
> techniques
> to do this with a single sided mask aligner. Can someone suggest
> some good
> article or book ?