contact bonding

The use of optical contact bonding allows the production of a final product with properties as good as the bulk solid.

Optical contact bonding is a glueless process whereby two closely conformal surfaces are joined together, being held purely by intermolecular forces.

Description of production of experimental 'Lab on a chip' via contact bonding RSC Publishing (Royal Society of Chemistry)

By 1900 optical contact bonding was being employed in the construction of optical prisms, and the following century saw further research into the phenomenon at the same time that ideas of inter-atom interactions were first being studied.