Abstract: An aluminum nitride sintered body has a metallized layer on its surface. The metallized layer contains tungsten, aluminum oxide and calcium oxide. Preferably, the metallized layer contains 40 to 96 percent by weight of a metal, 0.4 to 25 percent by weight of an aluminum oxide and 3 to 35 percent by weight of calcium oxide. In a method of forming a metallized layer on the surface of the aluminum nitride sintered body, such body is first formed by firing. Then, a metal paste of tungsten containing powder of calcium oxide and powder of aluminum oxide is provided. The metal paste is coated on the surface of the aluminum nitride sintered body which is then fired with the metal paste in an inert atmosphere.

Abstract: The present invention provides a sintered body of aluminum nitride comprising (i) aluminum nitride as a main component and (ii) at least one component selected from the group consisting of Zr, Hf, V, Nb, Ta, Cr, Mo, W, Fe, Co, Ni, Nd, Ho, Ti and compounds thereof in the total amounts of not greater than 1.0 wt. % and not less than 0.01 wt. % in terms of elements on the basis of sintered body, the sintered body being colored and having a thermal conductivity of at least 150 W/mK. The sintered body is useful for the preparation of circuit boards having printed circuits thereon and highly heat-releasing ceramic packages for semiconductive devices.

Abstract: The present invention provides a sintered body of aluminum nitride comprising (i) aluminum nitride as a main component and (ii) at least one component selected from the group consisting of Zr, Hf, V, Nb, Ta, Cr, Mo, W, Fe, Co, Ni, Nd, Ho, Ti, and compounds thereof in the total amounts of not greater than 1.0 wt. % and not less than 0.01 wt. % in terms of elements on the basis of sintered body, the sintered body being colored and having a thermal conductivity of at least 150 W/mK. The sintered body is useful for the preparation of circuit boards having printed circuits thereon and highly heat-releasing ceramic packages for semiconductive devices.

Abstract: The present invention provides a sintered body of aluminum nitride comprising (i) aluminum nitride as a main component and (ii) at least one component selected from the group consisting of Zr, Hf, V, Nb, Ta, Cr, Mo, W, Fe, Co, Ni, Nd, Ho, Ti and compounds thereof in the total amounts of not greater than 1.0 wt.% and not less than 0.01 wt.% in terms of elements on the basis of sintered body, the sintered body being colored and having a thermal conductivity of at least 150 W/mK. The sintered body is useful for the preparation of circuit boards having printed circuits thereon and highly heat-releasing ceramic packages for semiconductive devices.

Abstract: An aluminum nitride sintered body is mainly composed of aluminum nitride, contains 0.01 to 1.0 percent by weight of a rare earth element and 0.001 to 0.5 percent by weight of oxygen, and has thermal conductivity of at least 180 W/mK. According to a method of manufacturing such an aluminum nitride sintered body, aluminum nitride powder (201) is first prepared. At least one compound (203) containing a rare earth element is added to the aluminum nitride powder (201) to contain 0.01 to 1.0 percent by weight, in rare earth element conversion, of the compound, to be homogeneously mixed with each other. A formed body obtained by forming such mixed powder is sintered in a non-oxidizing atmosphere containing nitrogen at a temperature of 1500 to 2200.degree. C.

Abstract: A sintered body of aluminum nitride having a density of not smaller than 3.1 g/cm.sup.3, a coefficient of thermal conductivity of not smaller than 100 W/mk and preferably an average particle size of not larger than 5 .mu.m, which comprises aluminum nitride as a main component, 0.01 to 10.0% by weight of at least one oxide selected from oxides of the IIa and IIIa elements of the Periodic Table, 2.0% by weight or less of oxygen which is not contained in the oxide of the IIa and IIIa element and 1.0% by weight or less of at least one impurity metal which is not the IIa or IIIa element which has good thermal conductivity.

Abstract: An aluminum nitride sintered body mainly composed of aluminum nitride, contains 0.01 to 1.0 percent by weight of a rare earth element and 0.001 to 0.5 percent by weight of oxygen. Such a body has a thermal conductivity of at least 180 W/mK. For manufacturing such an aluminum nitride sintered body, aluminum nitride powder (201) is first prepared. At least one compound (203) containing a rare earth element is added to the aluminum nitride powder (201) to contain 0.01 to 1.0 percent by weight, in rare earth element conversion, of the compound. The ingredients are homogeneously mixed with each other. A green body is formed of the mixed powder and sintered at a temperature of 1500.degree. to 2200.degree. C. in a non-oxidizing atmosphere containing nitrogen.

Abstract: A connection structure between lead frames and a base plate of aluminum nitride, to be applied as a connection structure between components of a semiconductor apparatus, has a base plate made of a sintered body of aluminum nitride on which a semiconductor device is to be mounted. The lead frames are made of iron alloy containing nickel in 29 wt. % and cobalt in 17 wt. %. A silver solder is used for joining the base plate and the lead frames. A surface of the lead frame to be joined to the base plate is clad with a stress relief layer of oxygen-free copper of a high plastic deformability to relieve, by its plastic deformation, a thermal stress caused by a difference between a thermal expansion coefficient of the aluminum nitride base plate and that of the lead frame in a cooling process at the time of soldering. Preferably, only a portion of each lead frame to be joined to the base plate comprises an inner layer of an iron alloy containing 29 wt. % of nickel and 17 wt.

Abstract: A member for a semiconductor structure is constructed, for example, as a mounting, or as a cover, or as a heat sink. Such a component is obtained by joining an aluminum nitride insulating substrate and a radiating element. The metal material for forming the radiating member has a thermal conductivity of at least 120 W/mK and a thermal expansion coefficient within a range of 4 to 6.0.times.10.sup.-6 /K.sup.-1. Preferably the material forming the radiating element is made of a tungsten alloy containing copper by not more than 5 percent by weight.

Abstract: A member for a semiconductor apparatus for carrying or holding a semiconductor device, obtained by joining an aluminum nitride substrate and a radiating substrate, comprises an insulating member formed by an aluminum nitride sintered body to be provided thereon with the semiconductor device, a radiating member to be joined to the insulating member, which radiating member is mainly formed of a copper-tungsten alloy or a copper-molybdenum alloy, a stress relieving member interposed between the insulating member and the radiating member and a silver solder member for joining the insulating member, the stress relieving member and the radiating member with each other.

Abstract: The bonding apparatus has a holding device, a pressing device for pressure welding substances to be bonded to each other, and a superhigh vacuum bonding chamber provided with the holding device and the pressing device. A superhigh vacuum bonding preparatory chamber is connected with the superhigh vacuum bonding chamber through a gate valve and a conveyor is arranged for conveying the substances to be bonded between the superhigh vacuum bonding preparatory chamber and the superhigh vacuum bonding chamber. The preparatory chamber is provided with a rotary preparatory table having a plurality of stages for releasably supporting holders for holding the substances to be bonded, the preparatory table being moved to successive positions to register with the conveyor.