Thick film conductor paste composition for LTCC tape in microwave applications
AssigneeE.I. du Pont de Nemours and Company
InventorsPatricia J. Ollivier, Kenneth Warren Hang
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Abstract
This invention is related to thick film conductor compositions comprising electrically conductive gold powder, one or more glass frit or ceramic oxide compositions and an organic vehicle. It is further directed to the composition's uses for LTCC (low temperature co-fired ceramic) tape, for fabrication of multilayer electronic circuits and in high frequency microelectronic applications.
Claims12
A method of forming a multilayer circuit comprising:
- a) forming a patterned array of vias in a plurality of layers of green tape;
- b) filling the vias in the green tape layer(s) of step a) with a thick film composition;
- c) printing patterned thick film functional layers over a surface of any or all of the via-filled green tape layers of step b);
- d) printing patterned layers of a thick film conductive composition over the outermost surface of the green tape layers of step c), the thick film conductive composition comprising:
- i) gold powder;
- ii) an inorganic binder of glass frit consisting of 5-20 wt % B2O3, 1-44 wt % SiO2, 3-20 wt % Al2O3, 0-10 wt % Na2O, 0-4 wt % Li2O, 2-41 wt % P2O5, 5-16 wt % NaF, 0-9 wt % CaO, 0-3 wt % ZrO3, 0-19 wt % ZnO, 0-2 wt % BaO, and 0-11 wt % ZnF2, wherein the weight percent are based on the total glass composition;
- and
- iii) organic medium;
- e) laminating the printed green tape layers of step d) to form an assemblage comprising a plurality of unfired interconnected functional layers separated by unfired green tape;
- and
- f) cofiring the assemblage of step e).
A method of forming a multilayer circuit comprising:
- a) forming a patterned array of vias in a plurality of layers of green tape;
- b) filling the vias in the green tape layer(s) of step a) with a thick film composition;
- c) printing patterned thick film functional layers over a surface of some or all of the via-filled green tape layers of step b);
- d) laminating the printed green tape layers of step c) to form an assemblage comprising a plurality of unfired interconnected functional layers separated by unfired green tape;
- e) printing at least one patterned layer of a thick film conductive composition over the assemblage of step d), the thick film conductive composition comprising:
- i) gold powder;
- ii) an inorganic binders of glass frit consisting of 5-20 wt % B2O3, 1-44 wt % SiO2, 3-20 wt % Al2O3, 0-10 wt % Na2O, 0-4 wt % Li2O, 2-41 wt % P2O5, 5-16 wt % NaF, 0-9 wt % CaO, 0-3 wt % ZrO3, 0-19 wt % ZnO, 0-2 wt % BaO, and 0-11 wt % ZnF2, wherein the weight percent are based on the total glass composition;
- and
- iii) organic medium;
- and
- f) cofiring the assemblage and patterned layer(s) of step e).
A multilayer circuit comprising a thick film conductive composition, the thick film conductive composition comprising:
- i) gold powder;
- ii) an inorganic binders of glass frit consisting of 5-20 wt % B2O3, 1-44 wt % SiO2, 3-20 wt % Al2O3, 0-10 wt % Na2O, 0-4 wt % Li2O, 2-41 wt % P2O5, 5-16 wt % NaF, 0-9 wt % CaO, 0-3 wt % ZrO3, 0-19 wt % ZnO, 0-2 wt % BaO, and 0-11 wt % ZnF2, wherein the weight percent are based on the total glass composition;
- and
- iii) organic medium,
- wherein the composition has been processed to remove said organic medium and sinter said inorganic binder.
Dependencies are inferred from the claim text.