Abstract:
A substrate having high absorptance and emittance is produced by roughening the surface of the substrate, immersing the substrate in a first electroless plating bath having a low phosphorus to nickel concentration, then immersing the substrate in a second electroless plating bath having a phosphorus to nickel concentration higher than that of said first electroless plating bath. Thereafter, the resulting electroless nickel-phosphorus alloy coated substrate is immersed in an aqueous acidic etchant bath containing sulfuric acid, nitric acid and divalent nickel to develop a highly blackened surface on said substrate.
Abstract:
A metallization system for metallurgically bonding a semiconductor die to metallic conducting slugs as terminals at the same time, and at the same temperature, that a surrounding glass sleeve is hermetically sealed to the conducting slugs for forming a zener diode, for example, is disclosed. The metallization system comprises a combination of aluminum, tin and palladium, for bonding to molybdenum, the aluminum being vapor deposited followed by a vapor co-deposition of aluminum and tin and further followed by a vapor deposited layer of palladium.A method of making a device is disclosed wherein the die, two metal slugs of molybdenum and a preformed high temperature sealing glass are assembled together and subjected to a time-temperature cycle which includes a rapid rise to a high temperature at which metallurgical bonding of the die to the metal slugs and hermetic sealing of the glass to the metal slugs take place in a short time interval followed by rapid cooling of the assembly to a temperature slightly below the eutectic of aluminum and silicon.
Abstract:
Immersion of semiconductor devices, particularly diodes, having a defective tin plating thereon in a solution of 5 - 20 percent by weight trichloroacetic acid, 0.1 to 5 percent by weight of a compound selected from the group consisting of cationic, anionic, and nonionic surfactants and the balance water effectively removes the tin therefrom. The process is effective at room temperature but preferably is performed at approximately 100.degree. C.
Abstract:
A metallization system for metallurgically bonding a semiconductor die to metallic conducting slugs as terminals at the same time, and at the same temperature, that a surrounding glass sleeve is hermetically sealed to the conducting slugs for forming a zener diode, for example, is disclosed. The metallization system comprises a combination of aluminum, tin and palladium, for bonding to molybdenum, the aluminum being vapor deposited followed by a vapor co-deposition of aluminum and tin and further followed by a vapor deposited layer of palladium.A method of making a device is disclosed wherein the die, two metal slugs of molybdenum and a preformed high temperature sealing glass are assembled together and subjected to a time-temperature cycle which includes a rapid rise to a high temperature at which metallurgical bonding of the die to the metal slugs and hermetic sealing of the glass to the metal slugs take place in a short time interval followed by rapid cooling of the assembly to a temperature slightly below the eutectic of aluminum and silicon.
Abstract:
A metallization system for metallurgically bonding a semiconductor die to metallic conducting slugs as terminals at the same time, and at the same temperature, that a surrounding glass sleeve is hermetically sealed to the conducting slugs for forming a zener diode, for example, is disclosed. The metallization system comprises a combination of aluminum, tin and palladium, for bonding to molybdenum, the aluminum being vapor deposited followed by a vapor co-deposition of aluminum and tin and further followed by a vapor deposited layer of palladium.A method of making a device is disclosed wherein the die, two metal slugs of molybdenum and a preformed high temperature sealing glass are assembled together and subjected to a time-temperature cycle which includes a rapid rise to a high temperature at which metallurgical bonding of the die to the metal slugs and hermetic sealing of the glass to the metal slugs take place in a short time interval followed by rapid cooling of the assembly to a temperature slightly below the eutectic of aluminum and silicon.
Abstract:
An improved metallization system for semiconductor substrates comprising successive layers of at least one barrier metal and tin is disclosed. A semiconductor package comprising a housing of impervious material, a semiconductor device having the metallization system of this invention disposed in the housing and conductor means bonded to the tin on the semiconductor device is also disclosed. The system is of particular usefulness in double stud diode packages.
Abstract:
An improved method for encapsulating a semiconductor diode wherein a semiconductor chip and a pair of leads are surrounded by an insulating glass. The improvement comprising the providing of an alkaline free low temperature encapsulating glass for semiconductors consisting essentially of 11-15 weight percent silica, 7-11 weight percent alumina, 63-68 weight percent lead oxide, 4-10 weight percent lead fluoride and 5-10 weight percent borate.
Abstract:
A metallization system for metallurgically bonding a semiconductor die to metallic conducting slugs as terminals at the same time, and at the same temperature, that a surrounding glass sleeve is hermetically sealed to the conducting slugs for forming a zener diode, for example, is disclosed. The metallization system comprises a combination of aluminum, tin and palladium, for bonding to molybdenum, the aluminum being vapor deposited followed by a vapor co-deposition of aluminum and tin and further followed by a vapor deposited layer of palladium.A method of making a device is disclosed wherein the die, two metal slugs of molybdenum and a preformed high temperature sealing glass are assembled together and subjected to a time-temperature cycle which includes a rapid rise to a high temperature at which metallurgical bonding of the die to the metal slugs and hermetic sealing of the glass to the metal slugs take place in a short time interval followed by rapid cooling of the assembly to a temperature slightly below the eutectic of aluminum and silicon.