GB1099930A - Improvements in or relating to semiconductor devices - Google Patents

Abstract

1,099,930. Semi-conductor devices. FAIRCHILD CAMERA & INSTRUMENT CORPORATION. Jan. 4, 1967 [May 31, 1966]. No. 603/67. Heading H1K. Contact pads on a solid state circuit are formed on an insulating layer overlying the components and their interconnections, the pads being arranged so that they overlie circuit components. As shown, Fig. 3, an integrated circuit comprises a transistor 22 formed by diffusion in a silicon wafer and connected to other components by a conductor 32 deposited on a silicon dioxide layer 30. A second insulating layer 34 is deposited over the wafer, an aperture 36 is etched, and a contact pad 16 is deposited on the surface and is connected to region 26 by conductive material filling aperture 36. The connection to region 26 may also be made by etching an aperture 37 in oxide layer 30 and filling with conductive material simultaneously with the production of interconnection 32, depositing the second insulating layer 34 and etching an aperture to expose the first part of the connection, and then depositing the contact pad 16. In a modification, Fig. 4, region 26 is contacted by a conductive strip 52, formed simultaneously with interconnections 32, and extending a short distance over the surface of the oxide layer 30. The second insulating layer 34 is now deposited and part of strip 52 is exposed either by masking during the deposition or by etching. The pad 16 is then deposited on layer 34 and is provided with a portion 50 which contacts strip 52 to complete the connection. The second insulating layer may be of natural or synthetic silicates, refractory metal oxides, mixtures of silica and other metal oxides, and sintered glasses and may be applied by thermal vacuum deposition, sputtering or vapour phase deposition. The contact pads may be of aluminium vapour deposited and may be shaped by a photo-engraving technique. Connections may be applied to the pads by soldering, thermocompression bonding or ultrasonic bonding. The circuit may contain transistors, diodes, FET's, MOS devices, resistors, capacitors, or inductors and may be of the hybrid or thinfilm types.