Does any person know what the most popular method for forming an etch stop would
be?  Is it one of the following or some other method?

ion implant?
Gaseous diffusion?
Planar diffusion sources?
Spin-on diffusion sources?
Liquid source?

Does anyone know of any improved methids for wafer bonding than may have been
previously discussed?
I am familiar with the use of a spin on bonding method using a flowable
organosilane, any other better techniques.

Thank you for your time!

neal