M. Harz et W. Bruckner, STRESS REDUCTION IN ANODICALLY BANDED SILICON AND BOROSILICATE GLASS BY THERMAL-TREATMENT, Journal of the Electrochemical Society, 143(4), 1996, pp. 1409-1414
A well-known problem in packaging of micromechanical devices by anodic
bonding is the resulting bow of the devices. The present paper deals
with a method to change this bow after bonding by annealing the wafers
below the glass transition region. By means of laser optical curvatur
e measurement the change of the bow during several annealing procedure
s has been observed in situ. It is shown that the bow of bonded wafer
pairs can be reduced, removed, and even induced in the opposite direct
ion. The observed bowing behavior is explained by the structural relax
ation of borosilicate glass.