Kabushiki Kaisha Toshiba

Toshiba Materials Co., Ltd.

Noritaka Nakayama

Takayuki Naba

Hiromasa Kato

Katsuyuki Aoki

Takashi Sano

Hiroshi Komorita

Michiyasu Komatsu

Kiyoshi Iyogi

Takao Shirai

Katsuhiro Shinosawa

Kentaro Takanami

A silicon nitride substrate including silicon nitride crystal grains and a grain boundary phase and having a thermal conductivity of 50 W/m&#xb7;K or more, wherein, in a sectional structure of the silicon nitride substrate, a ratio (T2/T1) of a total length T2 of the grain boundary phase in a thickness direction with respect to a thickness T1 of the silicon nitride substrate is 0.01 to 0.30, and a variation from a dielectric strength mean value when measured by a four-terminal method in which electrodes are brought into contact with a front and a rear surfaces of the substrate is 20% or less. The dielectric strength mean value of the silicon nitride substrate can be 15 kV/mm or more. According to above structure, there can be obtained a silicon nitride substrate and a silicon nitride circuit board using the substrate in which variation in the dielectric strength is decreased.

Silicon nitride substrate and silicon nitride circuit board using the same

A silicon nitride substrate including silicon nitride crystal grains and a grain boundary phase and having a thermal conductivity of 50 W/m&#xb7;K or more, wherein, in a sectional structure of the silicon nitride substrate, a ratio (T2/T1) of a total length T2 of the grain boundary phase in a thickness direction with respect to a thickness T1 of the silicon nitride substrate is 0.01 to 0.30, and a variation from a dielectric strength mean value when measured by a four-terminal method in which electrodes are brought into contact with a front and a rear surfaces of the substrate is 20% or less. The dielectric strength mean value of the silicon nitride substrate can be 15 kV/rum or more. According to above structure, there can be obtained a silicon nitride substrate and a silicon nitride circuit board using the substrate in which variation in the dielectric strength is decreased.

A silicon nitride substrate including silicon nitride crystal grains and a grain boundary phase and having a thermal conductivity of 50 W/m&#xb7;K or more, wherein, in a sectional structure of the silicon nitride substrate, a ratio (TT) of a total length Tof the grain boundary phase in a thickness direction with respect to a thickness Tof the silicon nitride substrate is 0.01 to 0.30, and a variation from a dielectric strength mean value when measured by a four-terminal method in which electrodes are brought into contact with a front and a rear surfaces of the substrate is 20% or less. The dielectric strength mean value of the silicon nitride substrate can be 15 kV/mm or more. According to above structure, there can be obtained a silicon nitride substrate and a silicon nitride circuit board using the substrate in which variation in the dielectric strength is decreased.

There is provided a polycrystalline aluminum nitride substrate that is effective in growing a GaN crystal. The polycrystalline aluminum nitride base material for use as a substrate material for grain growth of GAN-base semiconductors, contains 1 to 10% by weight of a sintering aid component and has a thermal conductivity of not less than 150 W/m&#xb7;K, the substrate having a surface free from recesses having a maximum diameter of more than 200 &#x3bc;m.

Polycrystalline aluminum nitride base material for crystal growth of GaN-base semiconductor and method for manufacturing GaN-base semiconductor using the same

An electronic component module has a circuit board in which metal plates are bonded to both surfaces of a ceramic substrate, and an electronic component that is bonded to at least one surface of the metal plate and is operable at least 125&#xb0; C. The electronic component is bonded to the metal plate via a brazing material layer having a higher melting point than a operating temperature of the electronic component.

Electronic component module

A ceramic-metal composite includes a ceramic substrate, an active metal brazing alloy layer, and a metal plate bonded to the ceramic substrate through the active metal brazing alloy layer disposed therebetween. The active metal brazing alloy layer contains a transition metal that is at least one element selected from Group-8 elements specified in the periodic table. According to the above configuration, the following composite and device can be provided: the ceramic-metal composite that exhibits high bonding strength, heat cycle resistance, durability, and reliability even if the ceramic-metal composite is used in a power module and a semiconductor device including the ceramic-metal composite.

Ceramic metal composite and semiconductor device using the same

An electronic component modulehas a circuit boardin which metal platesandare bonded to both surfaces of a ceramic substrate, and an electronic componentthat is bonded to at least one surface of the metal plateand is operable at least 125&#xb0; C. The electronic componentis bonded to the metal platevia a brazing material layerhaving a higher melting point than a operating temperature of the electronic component

An aluminum nitride substrate includes an aluminum nitride sintered body containing a rare earth oxide as a sintering additive component. In the aluminum nitride substrate, a surface thereof is machined so that arithmetic average roughness Ra is 0.5 &mgr;m or less; an aggregate size of the sintering additive component present on the machined surface is 20 &mgr;m or less; and a total aggregate area in a unit area of the machined surface is 5% or less. A metal thin film is deposited on such machined surface with good intimate contact properties, and furthermore deposition accuracy or the like is improved.

Aluminum nitride substrate and thin film substrate therewith, and manufacturing method thereof

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&mdash;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.

Growing community of inventors

Yokohama, Japan

Noritaka Nakayama