Patent ID: 7670672

Claim:
A multilayer ceramic substrate comprising: a base and a wall defining a cavity including a bottom surface defined by an upper main surface of the base; and a laminated structure including a plurality of stacked base-material layers and a constraining interlayer arranged along a specific interface between the base-material layers; wherein each of the base-material layers is defined by a sintered body including a first powder including a glass material and a first ceramic material; the constraining interlayer includes a second powder including a second ceramic material that is not sintered at a temperature at which the glass material is melted and is in a state in which particles of the second powder are bonded by diffusion or flow of a portion of the first powder including the glass material in the base-material layers into the constraining interlayer during firing; the constraining interlayer is arranged at an interface between the wall and the base; a first conductive film is arranged between the base and the constraining interlayer; the first conductive film is arranged along substantially an entire perimeter of the cavity; and the first conductive film is arranged to extend from between the base and the wall to a portion of the bottom surface of the cavity.