| 摘要 |
<p>1,095,576. Semi-conductor controlled rectifiers. SIEMENS-SCHUCKERTWERKE A.G. July 26, 1965 [Aug. 12, 1964], No. 31865/65. Heading H1K. In a substantially monocrystalline silicon PNPN device, a first inner layer 2 is between 100Á and 200Á thick and has the lowest impurity concentration of the four layers, this concentration being substantially constant throughout the layer 2 and lying within the range from 10<SP>14</SP> to 2À5 x 10<SP>14</SP> per c.c., while the impurity concentration in the second inner layer 3 is of the same magnitude at its junction with the first inner layer 2 and rises, exponentially at first, with distance from the junction to a maximum between about 10<SP>2</SP> and 10<SP>4</SP> times this initial value, a rise by a factor e being achieved in a distance between 7Á and 13Á from the junction. A first outer layer 4 has an impurity distribution symmetrical with that of the second inner layer 3, the two layers having been produced either by a diffusion process or by pyrolitic decomposition of a gaseous silicon compound with controlled addition of doping material. The alloyed second outer layer 5 and sub-layer 7 have higher impurity concentrations, at least 10<SP>18</SP> per c.c.</p> |
