The present invention provides a ceramic circuit board comprising: a ceramic substrate and a metal circuit plate bonded to the ceramic substrate through a brazing material layer; wherein the brazing material layer is composed of Al-Si group brazing material and an amount of Si contained in the brazing material is 7 wt% or less. In addition, it is preferable to form a thinned portion, holes, or grooves to outer peripheral portion of the metal circuit plate. According to the above structure of the present invention, there can be provided a ceramic circuit board having both high bonding strength and high heat-cycle resistance, and capable of increasing an operating reliability as electronic device.

Ceramic circuit board

PROBLEM TO BE SOLVED: To make a substrate size small and to improve durability by reducing thermal stress of solder while preventing heat dissipation from decreasing owing to a void in spite of use of lead-free solder, with respect to a semiconductor device having semiconductor elements bonded to one surface of an insulating substrate made of a ceramic substrate having metal plates bonded to both surfaces and also having a metallic heat sink bonded to the other surface via the lead-free solder. SOLUTION: The semiconductor elements S, S' are bonded to the insulating substrate P such that two or more semiconductor elements of the same kind are not mounted on the one insulating substrate P, and the area A of a surface of the second metal plate M2 which is opposed to the heat sink B is set to be 1 to 2.5 times as large as the overall area At of the semiconductor elements S, S'. COPYRIGHT: (C)2011,JPO&INPIT

Semiconductor device and method of manufacturing the same

A power semiconductor module has a circuit assembly body, which includes a metal base, a ceramic substrate, and a power semiconductor chip, and is combined with a package having terminals formed integrally. The ceramic substrate of the module has a structure such that an upper circuit plate and a lower plate are joined to both sides of a ceramic plate, respectively, and the metal base and the ceramic substrate are fixed to one another using solder, thereby improving reliability and lengthening a life of a power semiconductor module by optimizing a ceramic substrate and a metal base thereof, the dimensions thereof, and material and method used for a join formed between the ceramic substrate and metal base.

Power semiconductor module

A highly reliable copper circuit-joined board that, in mounting a semiconductor element, a lead frame or the like on a ceramic substrate, enables the semiconductor element, the lead frame or the like to be strongly joined to the substrate without breaking or deformation of the substrate found in conventional joining methods, such as brazing and joining using a copper/copper oxide eutectic crystal. Any one of an interposing layer comprising a brazing material layer comprising silver and/or copper as a main component and an active metal or an interposing layer having a two-layer structure comprising a first interposing layer comprising the brazing material layer or a high-melting metallizing layer and a second interposing layer, having a melting point of 1000° C. or below, comprising Ni, Fe, Cu as a main component in that order from the substrate side, is formed on a ceramic substrate, and a conductor layer, comprising copper as a main component, which, in both the lengthwise and widthwise directions, is at least 0.05 mm shorter than the interposing layer, is formed on the interposing layer to prepare a copper circuit-joined board. The copper circuit-joined board may comprise the base board having thereon an outer layer comprising Ni as a main component. A semiconductor element is mounted on the copper circuit-joined board to prepare a semiconductor device.

Copper circuit junction substrate and method of producing the same

A packaged power semiconductor device (24) with voltage isolation between a metal backside (34) and the terminals (38) of the device. A direct-bonded copper ('DBC') substrate (28) is used to provide electrical isolation and good thermal transfer from the device to a heatsink. A power semiconductor die (26) is soldered or otherwise mounted to a first metal layer (30) of the DBC substrate. The first metal layer spreads heat generated by the semiconductor die. The leads and die may be soldered to the DBC substrate in a single operation. In one embodiment, over 3,000 Volts of isolation is achieved. In another embodiment, the packaged power semiconductor device conforms to a TO-247 outline.

Electrically isolated power semiconductor package

This invention provides a silicon nitride circuit board in which a metal circuit plate is bonded to a high thermal conductive silicon nitride substrate having a thermal conductivity of not less than 60 W/m K, wherein a thickness D s of the high thermal conductive silicon nitride substrate and a thickness D M of the metal circuit plate satisfy a relational formula D s ≦2D M . The silicon nitride circuit board is characterized in that, when a load acts on the central portion of the circuit board which is held at a support interval of 50 mm, a maximum deflection is not less than 0.6 mm until the silicon nitride substrate is broken. The silicon nitride circuit board is characterized in that, when an anti-breaking test is performed to the circuit board which is held at a support interval of 50 mm, an anti-breaking strength is not less than 500 MPa. The metal circuit plate or a circuit layer are integrally bonded on the silicon nitride substrate by a direct bonding method, an active metal brazing method, or an metalize method. According to the silicon nitride circuit board with the above arrangement, high thermal conductivity and excellent heat radiation characteristics can be obtained, and heat cycle resistance characteristics can be considerably improved.

Silicon nitride circuit board

A semiconductor module is provided with a high thermal-conductivity silicon nitride circuit board (10) having a high coefficient of thermal conductivity of 60 W/m.K or more, a semiconductor chip (7) mounted on the board (10), a metallic circuit board (3) stuck to the element mounting surface of the board (10), and a metallic plate (4a) stuck to the surface of the board (10) opposite to the element mounting side and to a device casing (9) or mounting board. The structure of the module is simplified and the size of the module is reduced. The heat dissipating property, structural strength, and heat cycle resistance of the module is improved.

Silicon nitride circuit board and semiconductor module

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.

Ceramic circuit board with a curved lead terminal

This invention provides a ceramics circuit board comprising: a ceramics base board (1); a metal circuit plate (7A to 7E) integrally bonded onto a surface of the ceramics base board (1); a terminal connecting port (3A to 3E) formed by bending a part of the matal circuit plate for connecting a terminal (4) of a module, the terminal connecting port being formed so that the terminal connecting port being raised from a surface of the ceramics base board (1), and a curvature radius (R₁, R₂) of the bended portion provided on the terminal connecting port is set to 0.2 mm or more. A communication hole such as groove or through hole may also be formed at a bonding surface between the metal circuit plate and the ceramics base board.

Kazuo Ikeda

Papers

Silicon nitride circuit board

Silicon nitride circuit board and semiconductor module

Ceramic circuit board with a curved lead terminal

Ceramics circuit board