Laminated glass article with low compaction and method for forming the same

Abstract

A strengthened glass article (100), such as a substrate for a p-Si based transistors, includes first and second glass cladding layers (104, 106) and a glass core layer (102) disposed therebetween. A coefficient of thermal expansion [CTE] of each cladding layer (104, 106), which can be made of the same glass, is at least 1×10−7° C.−1 less than that of the core layer (102). Each of the core and cladding layers has a strain point less than 700° C. A compaction of the glass article (100) is at most about 20 ppm [see FIG. 1]. A method includes forming a glass article and/or heating a glass article to a first temperature of at least about 400° C. The glass article has a glass core layer (102) and a glass cladding layer (104, 106) adjacent to the core layer. The glass article is maintained at a temperature within a range of from 400° C. to 600° C. for a holding period from 30 to 90 minutes and subsequently cooled to a temperature of at most 50° C. over a cooling period from 30 seconds to 5 minutes. The glass article (100) for heat strengthening may have been produced by the fusion overflow down draw process, e.g. as depicted in FIG. 3.

Dependencies are inferred from the claim text.