GB1223704A - Semiconductor device - Google Patents

Abstract

1,223,704. Semi-conductor devices. HITACHI Ltd. 17 April, 1968 [19 April, 1967; 4 May, 1967], No. 18194/68. Heading H1K. One or more semi-conductor device bodies with PN junctions terminating at one major face and junctionless semi-conductor terminal bodies are disposed in spaced relationship with their major faces in two parallel planes. A beam lead in one plane electrically connects one device body with another or with a terminal body while a connection formed on an insulating support disposed adjacent the other plane is connected to said other device or terminal body. A typical assembly (Fig. 3) is prepared from a silicon wafer by diffusing through oxide masking to form the desired devices at at least one face and then evaporating or electroplating on aluminium or gold 24 to form electrodes which are interconnected by heavier deposits of aluminium, chromium or molybdenum constituting beam leads 20, 21. Isolation of the elements is effected by subsequently etching away the silicon at 26, using photoresist techniques. The assembly is finally mounted by soldering contacts 31 on the terminal bodies to metallized tracks 32 on ceramic base 21. As shown the lower faces of the device bodies carry an insulating layer but they may if desired be connected to tracks on the substrate to provide external connections or interconnections. Gold or solder balls may be used to form connections to the metallization on the substrate which may alternatively consist of an oxide coated polycrystalline semi-conductor material. To reinforce the structure a glass or resin layer may be formed over the beam leads. The two levels of interconnection afforded by the invention are particularly useful where interconnections need to cross one another.