Two semiconductor substrates, each having a polished surface and at least one groove is formed in the surface of at least one of the two substrates, are tightly and inseparably joined by the steps of wetting the polished surface of at least one of the two substrates with a liquid not containing any solute...http://www.google.com.au/patents/US4962062?utm_source=gb-gplus-sharePatent US4962062 - Method of tightly joining two semiconductor substrates
