Patent ID: 11059738

Abstract:
A low CTE boro-aluminosilicate glass having a low brittleness for use in wafer-level-packaging (WLP) applications is disclosed. The glass comprises a composition in mol-% of SiO2: 60-85, Al2O3: 1-17, B2O3: 8-20, Na2O: 0-5, K2O: 0-5, MgO: 0-10, CaO: 0-10, SrO: 0-10, and BaO: 0-10. An average number of non-bridging oxygen per polyhedron (NBO) is equal to or larger than −0.2 and a ratio B2O3/Al2O3 is equal to or larger than 0.5. The NBO is defined as NBO=2×Omol/(Simol+Almol+Bmol)−4. A glass carrier wafer made from the low CTE boro-aluminosilicate glass and a use thereof as a glass carrier wafer for the processing of a silicon substrate are also disclosed, as well as a method for providing a low CTE boro-aluminosilicate glass.