R. Hsu et al., MODIFIED OXIDE SOL-PRECIPITATION (MOSP) APPROACH FOR SYNTHESIZING BOROPHOSPHOSILICATE GLASSES AND GLASS-CERAMICS, Chemistry of materials, 8(1), 1996, pp. 107-113
A modified oxide sol-precipitation process (MOSP) was used to synthesi
ze borophosphosilicate glasses and glass-ceramics utilizing boron oxid
e and phosphorous pentoxide precursors. The oxide precursors were used
to form alkoxides in situ, which were then partially hydrolyzed. Exce
ss ammonium hydroxide was added to initiate a precipitation reaction,
The resultant precipitate was centrifuged and separated from the super
natant liquid. The thermal properties of the dried precipitates were a
nalyzed and the precipitates were accordingly heat treated to 800 degr
ees C, in order to crystallize the boron phosphate phase. Pressureless
sintering was used to sinter the powders and form glass-ceramics, Mic
ro-structures of the sintered samples were then characterized using el
ectron microscopy, and the dielectric properties were measured. Dielec
tric measurements indicate that the sintered glass-ceramics possess di
electric constants less than 4.0 and dissipation factors less than 0.0
01 at a frequency of 1 MHz. Results of these studies show that the mod
ified oxide sol-precipitation is a viable approach for synthesizing bo
rophosphosilicate glass-ceramics for use as substrate materials in mic
roelectronic packaging.