Abstract: The present invention provides a ceramic circuit board including: a ceramic substrate; a plurality of metal circuit plates bonded to a surface of the ceramic substrate; and parts including semiconductor element integrally bonded to a surface of the metal circuit plates through a solder layer, wherein at least peripheral portion of one metal metal circuit plate to which the parts are solder-bonded and is adjacent to the other metal circuit plates is formed with a projection for preventing solder-flow. According to the structure described above, there can be provided a ceramic circuit board which is free from short-circuit due to the solder-flow or bonding defects of the parts thereby to have an excellent operating reliability, and is capable of being easily mass-produced with a high production yield.

Abstract: There is provided a semiconductor module which comprises a high thermal conductive silicon nitride substrate 10 having a thermal conductivity of 60 w/m·k or more, a semiconductor element 7 mounted on this high thermal conductive silicon nitride substrate 10, metal circuit plates 3 which are bonded on the semiconductor element-mounted side of this high thermal conductive silicon nitride substrate 10 and single metal plate 4a which is bonded to a side opposing to the semiconductor element-mounted side of this high thermal conductive silicon nitride substrate and is bonded on an apparatus casing 9 or a mounting board. By this constitution, there can be provided a semiconductor module having a simple structure, which can be miniaturized, and having an improved structure strength and an excellent heat cycle resistance property without requiring a heat sink plate or the like.

Abstract: A ceramic circuit board is characterized by being constituted by bonding a ceramic substrate 2 and a metal circuit plate 3 to each other through a silver-copper-based brazing material layer 5 containing at least one active metal selected from Ti, Zr, Hf, V, Nb and Ta, and wherein the Vickers hardness of a reaction product layer 6 generated by causing the silver-copper-based brazing material layer 5 and the ceramic substrate 2 to react with each other is 1,100 or more. At least one element selected from In, Zn, Cd, and Sn is preferably contained in the silver-copper-based brazing material layer 5. Further, 0.1 to 10.0 wt % of carbon powder is preferably contained in the brazing material layer 5. According to the above arrangement, there can be provided a ceramic circuit board in which cracks are effectively suppressed from being formed even after a thermal cycle is repeatedly applied for a long period of time, i.e.

Abstract: A ceramic circuit board wherein a copper circuit plate is directly bonded at a predetermined position on a ceramic substrate and heat is applied; or the copper circuit plate is integrally bonded through a brazing material containing an active metal, such as Ti, Zr and Hf; and a semiconductor element is bonded onto a semiconductor element mounting portion of the copper circuit plate through a solder layer. The copper plate element is formed with grooves or holes thereon and is bonded on the semiconductor element mounting portion of the copper circuit plate, and the semiconductor element is integrally bonded onto a surface of a grooved or holed side of the copper plate element through a solder layer.

Abstract: This invention provides a ceramic circuit board comprising: a ceramic base board; a metal circuit plate integrally bonded onto a surface of the ceramic base board; a terminal connecting port formed by bending a part of the metal circuit plate for connecting a terminal of a module, the terminal connecting port being formed so that the terminal connecting port is raised from a surface of the ceramic base board, and a curvature radius of the bent portion provided on the terminal connecting port is set to 0.2 mm or more. An empty communication hole such as groove or through hole may also be formed at a bonding surface between the metal circuit plate and the ceramic base board.