Hitachi, Ltd.

Nisshin Steel Co., Ltd.

Masahiko Itoh

Heihatiro Midorikawa

Akira Minato

Shiro Kobayashi

Michihiko Aizawa

Masakiyo Izumiya

Yasumasa Furutani

Kenzi Machizawa

Noriyuki Ohnaka

Takehiko Ito

Kiichiro Katayama

Teruo Yamaguchi

Kazutoshi Itoh

Kenji Machizawa

Mituru Kubo

Emiko Minowa

Emiko Murofushi

Narutoshi Kazama

A lead frame of a plastic encapsulated type semiconductor device is provided with a coating film which has a solderability higher than a solderability of a basic metal of the lead frame, and the coating film has a corrosion potential higher than a corrosion potential of the basic metal. The coating film protects the basic metal from corrosion caused by the plastic encapsulated member. The coating film of the lead frame made of a Fe-Ni alloy is an alloy comprising metal selected from Mo, W, Au, Cr, Cu, metals of the platinum group and a metal selected from Fe, Co, and Ni.

Lead frame for semiconductor device

A body, particularly a thin layer, of aluminium or aluminium alloy is given a corrosion-resistant bright dense barrier-type protective layer. The layer has a thickness in the range 50 to 500 nm and comprises aluminium oxide and a chelate complex of aluminium and at least one organic chelating compound. The layer is formed by contacting the surface with a solution of the chelating compound of pH 2 to 7 and, optionally, performing oxidative electrolysis.

Aluminium and aluminium alloy having corrosion-resistant protective

A metallization film layer disposed on a semiconductor chip is made of Cu alloy which contains a metal element less noble than Cu and whose balance consists of Cu and unavoidable impurities. The metal element less noble than Cu is at least one kind of members selected from the group consisting of Al, Be, Cr, Fe, Mg, Ni, Si, Sn and Zn. Cu alloy as the metallization film layer improves corrosion resistance by adding a trance amount of a metal element less noble than Cu within such a range where electric conductivity is not much reduced to Cu without lowering high electric conductivity, high heat resistance and high electro-migration resistance of Cu.

Semiconductor device

A method of descaling stainless steel which provides a smooth and glossy surface, comprises the steps of (a) anode-electrolyzing stainless steel having scales thereon in an aqueous neutral salt solution, (b) anode-electrolyzing or immersing the stainless steel in an aqueous alkaline solution. Steps (a) and (b) are performed in the order of either (a), (b), (a). The method further comprises the step of cathode-electrolyzing the stainless steel treated in the previous two steps in an aqueous nitric acid solution or immersing it in an aqueous solution of a mixture containing nitric acid and fluoric acid.

Method and apparatus for descaling stainless steel

A semiconductor module comprises semiconductor elements, cooling structures for cooling the semiconductor elements by liquid refrigerant, and a housing for accommodating the semiconductor elements and the cooling structures, wherein within the housing, there is supplied or enclosed sealingly a reactive gas which reacts with ions of a metal constituting the cooling structures to form a chemical compound hard to dissolve to the refrigerant but does not react with the metal itself constituting the cooling structures.

Semiconductor module and an electronic computer using the semiconductor

A hermetically closed circulation type, vapor absorption refrigerator which comprises a high temperature regenerator, a low temperature regenerator a condenser, an evaporator, an absorber and heat exchangers in a hermetically closed circulation system as essential constituent members composed of iron-based materials, where refrigeration is produced by repetitions of concentration of an absorbing solution sealed into the circulation system, dilution with a cooling medium and heat exchange, the inside wall of the high temperature regenerator being provided with a composite film of molybdenum oxides and iron oxide can be operated stably with a high reliability or corrosion resistance.

Hermetically closed circulation type, vapor absorption refrigerator

An absorption type refrigerator has an aqueous absorbing solution. The absorbing solution comprises lithium bromide solution, 5-150 ppm by weight of NO.sub.3.sup.- and 0.1-0.4% by weight of LiOH, and is free from any triazole compounds. The absorbing solution further includes octyl alcohol.

Absorption type refrigerator and absorbing solution therefor

A silver electrode (4) on a lead frame (2) is bonded to an aluminum electrode (5) on a silicon chip (1) with a copper wire (3). The resulting semiconductor device was immersed in a solution of benzotriazole in ethyl alcohol. An Ag-benzotriazole film (6) was formed on the surface of the silver electrode (4) and a Cu-benzotriazole film (7) was formed on the surface of the copper wire (3), while an Al-benzotriazole film (8) was formed on the surface of the aluminum electrode (5). Even if water penetrates into the semiconductor device, the silver electrode (4), the aluminum electrode (5) and the copper wire (3) are effectively protected by the anti-corrosive Ag-benzotriazole film (6), Cu-benzotriazole film (7) and Al-benzotriazole film (8) to exhibit excellent damp-proof.

Resin packaged semiconductor device having a protective layer made of a

A process for the partial hot dipping of a long steel strip is disclosed which comprises forming an oxidation-inhibiting film, oxygen-impermeable and thermally stable in a hot-dipping bath, which film is produced by the chemical reaction of an iron content in the steel strip with an oxidation inhibiting film-forming agent, such as an inorganic phosphoric acid compound, on a predetermined area of the steel strip surface, forming, as required, an intermediate layer comprising an inorganic binder, such as water glass, on the resulting film, forming a carbon-containing, plateing-stopping film as a top coat on the intermediate layer, and hot dipping the steel strip.

Process for partial hot dipping of steel strips

In a hermetically circulating absorption type refrigerator including a regenerator, a condenser, an evaporator, an absorber and a heat exchanger, the regenerator has an absorbing solution heating tube flux provided between tube plates. The tube plates are encased within a shell of the regenerator. Non-soluble electrodes are arranged between each of the tube plates and the shell. Then, an anti-corrosive current is made to flow through at least one of an end portion of the heating tube, the tube plates and the shell to thereby enhance the anti-corrosion effect together with an anti-corrosive agent or inhibitor.

Hermetically circulating, absorption type refrigerator

In a hermetically circulating, absorption type refrigerator based on a closed circulation system of constituent members comprised of a successive communication of a regenerator, a condenser, an evaporator, an absorber and a heat exchanger, refrigeration being produced by repetitions of concentration, refrigerant dilution, and heat exchange of an aqueous concentrated lithium bromide solution sealed in the circulation system, the aqueous concentrated lithium bromide solution contains at least one each of (a) an inhibitor having a boiling point higher than the solution temperature in the regenerator and (b) an inhibitor having a boiling point lower than the solution temperature in the regenerator. Corrosion of metallic materials used in a refrigerant circulation loop of the refrigerator and those in the absorbing solution circulation loop can be effectively prevented.

In a hermetically circulating, absorption type refrigerator based on a closed circulation system of constituent members comprised of a successive communication of a regenerator, a condenser, an evaporator, an absorber and a heat exchanger, refrigeration being produced by repetitions of concentration, refrigerant dilution, and heat exchange of an aqueous concentrated lithium bromide solution sealed in the circulation system, a hydrogen gas generated in the refrigerator is continuously converted to water, condensed and removed or returned to the refrigerator as a refrigerant. The pressure increase in the refrigerator can be prevented, and a high refrigerating performance can be continuously maintained without any special maintenance.

A hermetically circulating, absorption type refrigerator based on a closed circulation system comprised of a successive communication of a regenerator, a condenser, an evaporator, an absorber and a heat exchanger, parts or the whole of said constituent members in contact with an absorbing solution being comprised of a copper material selected from copper and copper alloy, and refrigeration being produced by repetitions of concentration, refrigerant dilution and heat exchange of an aqueous lithium bromide solution sealed in the circulation system is characterized in that the absorbing solution is an aqueous lithium bromide solution containing (a) a nitrate and (b) at least one triazole compound selected from benzotriazole and tolyltriazole, and has a particularly distinguished corrosion resistance.

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Hitachiota, Japan

Masahiko Itoh