Patent ID: 7381283
Filing Date: 2008-06-03
Classification: B32B,C04B,H01L,H05K

Abstract:
1. A method for reducing shrinkage during sintering low-temperature-cofired ceramics, the ceramics comprising a dielectric portion and a heterogeneous material portion, the method comprising the steps of: (a) providing a dielectric body comprising at least one dielectric layer of low temperature-cofired ceramic and that comprises at least one active area wherein said active area is disposed with at least one heterogeneous material pattern, and said heterogeneous material pattern comprises at least one heterogeneous material component and/or module; (b) positioning a constraining layer on the top of the dielectric body to form a monolithic structure, the constraining layer comprising at least one window and wherein the edge of the active area of the dielectric layer each falls within the window in vertical direction; wherein the constraining layer positioned on the top of the dielectric body is a low-sintering-temperature constraining layer with a sintering temperature lower than that of the dielectric layer and comprises about 1 wt% to about 10 wt% of vanadium oxide to lower the sintering temperature of the constraining layer to a temperature less than the sintering temperature of the dielectric layer; (c) firing the monolithic structure to a temperature first to sinter the constraining layer before the low-temperature-cofired ceramic starts to sinter then to sinter the low-sintering-temperature ceramic to reduce shrinkage of the low-temperature-cofired ceramic; and (d) singulating the monolithic structure along a cutting line to provide the low-temperature-cofired ceramics, wherein the cutting line is disposed in the area formed between the edge of the window and the edge of the active area to provide a low-temperature-cofired ceramic comprising vanadium oxide.