Circuit module connections

An electronic circuit package comprising:

• first and second modules each having opposite connecting surfaces, at least a part of one of said connecting surfaces of one of said modules being contiguous to at least a part of one of said connecting surfaces of the other of said modules, said modules each being a low temperature co-fired ceramic (LTCC) monolithic structure comprising:
• a plurality of cofired ceramic dielectric layers in a stacked assembly, and
• a conductive pattern on one surface of some of said plurality of dielectric layers such that said conductive patterns are separated by said dielectric layers in said stacked assembly,
• the other of said connecting surfaces of each module being on opposite sides of said stacked assembly, and said connecting surfaces having co-fired mating features therein,
• wherein said first module has said mating features comprising a first pattern of protrusions projecting from one of its connecting surfaces,
• said second module has said mating features comprising a second pattern of depressions in one of its connecting surfaces, said patterns having at least pattern portions in mating engagement with each other, with protrusions of said portions of said first pattern being received in depressions of said portions of said second pattern, and
• wherein said opposite connecting surface of at least one module has the other of protrusion and depression mating features for making electronic circuit package connections.