Ceramic multilayer substrate manufacturing method and un-sintered composite multilayer body

The ceramic multilayer substrate manufacturing method of the present invention is: First, by interposing an un-sintered multilayer multi-substrate (13) between the first and second shrinkage control layers (14a, 14b), an un-sintered composite multilayer body (11) is prepared. The first and second shrinkage control layers (14a, 14b) mainly contain aluminum powder, the un-sintered multilayer multi-substrate (13) mainly contains low-temperature firing glass ceramic powder. Then dispose a cut groove (16) on a major surface (11a) of the un-sintered composite multilayer body (11) to a depth penetrating through the shrinkage control layer (14a) and the un-sintered multilayer multi-substrate (13), reaching the other shrinkage control layer (14b), and not reaching the other major surface (11b) of the un-sintered composite multilayer body (11). Then the un-sintered composite multilayer body (11) with the cut groove (16) is sintered under the sintering condition of the low-temperature firing glass ceramic powder, the un-sintered shrinkage control layers (14a, 14b) are removed, and ceramic multilayer substrates are produced. Thus, high-precision ceramic multilayer substrates can be produced, causing few division failures when dividing a multilayer multi-substrate into ceramic plural multilayer substrates.