| 摘要 |
<p>1358294 Semi-conductor devices SIEMENS AG 28 June 1971 [13 July 1970] 30103/71 Heading H1K A hypersensitive P-N junction varactor diode having a monotonic C-V characteristic and being capable of accurate reproduction in batch manufacture is made by diffusing into an N-type body (initial doping conc. N B ) further N-type impurities in such a way that part of the diffused doping profile approximates realistically to an exponential function, and then diffusing in a high concentration of P-type impurities so that a P-N junction is formed at a depth at which the N-type doping concentration is No, where N B /N 0 #6.1 x 10<SP>-3</SP>. For a Si varactor, e.g. formed in an epitaxial layer, the N and P-type dopants are preferably P and B respectively.</p> |
