Abstract: A method for producing a semiconductor device, is composed of steps of: covering a lower side of a semiconductor wafer with a heavy metal and disposing the semiconductor wafer in a chamber; causing the heavy metal to diffuse into the semiconductor wafer by heating the semiconductor wafer with a heat source having a small thermal capacity; and thereafter, ceasing to heat with the heat source, then charging the chamber with a cooling gas.

Abstract: A method for eutectically attaching a silicon chip to a gold-coated substrate. Prior to heating and scrubbing of the silicon chip against the gold surface, a gold lattice structure is placed between the silicon chip bottom surface and the gold surface. The gold lattice structure contacts the silicon chip bottom surface over an area equal to less than ten percent of the total surface area of the chip bottom surface. The point source contact between the gold lattice and silicon chip promotes formation of the gold/silicon eutectic alloy at temperatures of between 400.degree. to 475.degree. C. The gold/silicon eutectic alloy spreads between the silicon chip bottom surface and gold top surface to provide eutectic bonding. The method is especially useful in bonding relatively large silicon chips or dies to gold-coated substrates wherein the bottom surface or back side of the chip is not coated with a protective metal layer.

Abstract: An improved method for eutectically bonding a silicon wafer into a cavity of a packaging body. A gold/silicon eutectic alloy cladding is formed on a ribbon made of gold. A strip is cut from the ribbon and placed into the package cavity with the cladding side up. Then a die is placed onto the strip on top of the gold/silicon cladding. The die is then scrubbed at a temperature of approximately 400.degree. C. and the gold/silicon cladding acts as a catalyst to form a gold/silicon eutectic bond between the die and the packaging body.

Abstract: Gold is diffused into a silicon substrate by first depositing an ultrathin layer of gold on one of the main faces of the substrate and then by heating the substrate to a temperature range of about 300.degree.-850.degree. C., instead of to about 1000.degree. according to the prior art. Then, following the removal of the remaining gold layer from over the substrate, the latter is reheated to a higher temperature ranging from about 700.degree. C. to about 1000.degree. C. for activating the diffused gold. The gold diffusion at the reduced temperature serves to decrease the surface irregularities of the substrate as a result of gold-silicon alloy zones created at the interface between gold layer and silicon substrate during the thermal diffusion process.

Abstract: An improved method for eutectically bonding a silicon wafer onto a gold preform is described. A gold/silicon seed is placed on a pure gold preform. Then a die is placed onto the pure gold preform and the gold/silicon seed, wherein the seed acts as a catalyst to form an eutectic bond.

Abstract: An improved method for eutectically bonding a silicon wafer onto a gold preform is described. A gold/silicon seed is placed on a pure gold preform. Then a die is placed onto the pure gold preform and the gold/silicon seed, wherein the seed acts as a catalyst to form an eutectic bond.

Abstract: A method for diffusing a metal dopant into a semiconductor switching device is provided by the use of a rapid thermal heating apparatus. This method provides a procedure for the selectively placing of a metal dopant in a region of the device or circuit. This aids in increasing the manufacturing yields of the switching device, and increases the number of active traps for minority carriers.