Interactions between beryllia and high-lead glasses

Interactions between BeO substrates and high-lead glasses of typical composition for hybrid thick films have been studied by means of secondary neutral mass spectrometry. The Be atomic concentration on top of glass layers, 2-40 mum thick, prepared at various temperatures T(f), ranging from 750 to 1000-degrees-C have been measured. The results give insight of Be solubility values from 0.5 to about 6 at. %, according to the glass type and firing temperature, and diffusion coefficients higher than 10(-10) cm2/S. Moreover, the diffusion mechanism appears quite different from that involved in interactions between the same glasses and alumina substrates, since no correlated diffusion process has been observed in the present case.