Semiconductor devices and methods of making same

摘要

958,242. Semi-conductor devices; circuit assemblies. TEXAS INSTRUMENTS Inc. May 6, 1960 [May 6, 1959], No. 16071/60. Headings H1K and H1R. [Also in Division H3] A semi-conductor device comprises a semi-conductor substrate with a monocrystalline semi-conductor layer in or on one surface, discrete regions in or on the layer providing the electrical properties of at least two different types of circuit element. In the embodiment comprising the gated bi-stable multivibrator circuit shown in Fig. 2a, a monocrystal wafer of N type germanium, silicon, gallium arsenide, aluminium antinonide or indium antinon- ide is first attached with solder glass over suitably arranged ohmic contact strips 33, 38, 40 (Fig. 1), to intrinsic semiconductor wafer 10, which is provided with additional tabs 68, 70, 72, 74, 76. A layer of P-type material is formed over the entire surface by acceptor diffusion, and N-type inclusions formed in selected areas of this layer by donor diffusion. The wafer is then selectively etched to divide it into two sub-wafers 12, 14 and to leave on sub-wafer 12 two double emitter NPN mesa-type transistors TR-2 (Fig. 3, not shown), TR-3, a single emitter mesa transistor TR-1, a PN mesa diode D 3 and two zigzag P-type zones 32, 42 forming extensions of the base zones of transistors TR-2 and TR-3 respectively. These zig-zag zones form resistors R 1 and R 3 in the circuit and are capacitively linked via the reverse biased PN-junctions to the underlying strips of N-type material forming resistors R 2 , R 4 . Plated ohmic contacts are provided on N-type inclusions in the diffused P-type layer on wafer 14 forming diodes D 2 , D 7 . Silicon dioxide dielectric coatings 64 and plated metal electrodes 66 are provided on selected areas of the P layer on wafer 14 to form coupling capacitors C 1 , C 2 . Ohmic contacts are also plated on the emitter and collector zones of the several transistors and on the anode of diode D 3 and interconnecting wires provided as shown. The sub-wafers 12, 14 may be replaced by integral N-type zones formed by donor diffusion into appropriately shaped areas of the substrate wafer 10. Specifications 945,734, 958,244, 958,245, 958,246, 958,247, 958,248 and 958,249 are referred to.