Method of making multilayered glass-ceramic structures having an internal distribution of copper-based conductors

A method of forming a glass-ceramic composite structure with copper based metallurgy comprising:

• forming at least one green sheet comprised of a thermoplastic organic binder having dispersed therein particles of a crystallizable glass having a crystallization temperature below the melting point of copper;
• forming on a surface of a first said green sheet a pattern of a nonrefractory copper based conductor forming composition wherein the predominant component of said conductor is copper;
• superimposing a second said sheet on said surface of said first sheet to sandwich said pattern therebetween;
• laminating said superimposed sheets together;
• heating said laminate in an ambient of hydrogen and H.sub.2 O in a ratio of H.sub.2 /H.sub.2 O=about 10.sup.-4 to about 10.sup.-6.5 to a burn-out temperature in the range between the anneal and softening points of said glass and maintained thereat for sufficient time to decompose and eliminate said binder,
• substituting an inert atmosphere for said ambient;
• and
• heating said laminate to the crystallization temperature of said glass for coalescence of said glass particles and crystallization thereof into a glass-ceramic structure have a copper-based conductor pattern extending within the interior thereof.