| 摘要 |
<p>1,232,486. Semi-conductor devices. INTERNATIONAL BUSINESS MACHINES CORP. 27 Sept., 1968 [17 Oct., 1967], No. 45902/68. Heading H1K. An integrated switching circuit comprises a switching device such as a thyristor 25 in a first area of an n(p)-type epitaxial layer 24 on a p(n)-type substrate 10 and an associated diode 27 and resistor 32 in a second area of the epitaxial layer 24, the areas being separated by p + (n + ) isolation zones 26. More than one such pair of areas may be provided. In the Si circuit disclosed buried n+ layers 22, 22<SP>1</SP> are formed by redistribution of prediffused As during the growth of the As-doped n-type epitaxial layer 24. B is diffused through the layer 24 to form the p + isolation zones 26. The thyristor 25 comprises B-diffused p-type anode and base regions P1, P2 and a P-diffused n-type cathode region N2. The p-type diode and resistor regions P3, P4 in the second area are formed simultaneously with the regions P1, P2. A1 electrodes join the various components as shown. A connection 58 may be provided to by-pass the parasitic capacitances across the junctions 48, 50 between the substrate 10 and the respective areas. A further electrode may be situated on the region 30 to enable the anode junction 42 to be reverse biased if desired. This has the effect of reducing the capacitance in the main current path of the thyristor.</p> |
