| 摘要 |
1484218 Semi-conductor rectifiers SIEMENS AG 30 Oct 1975 [13 Feb 1975] 44795/75 Heading H1K In a semi-conductor rectifier comprising a lightly doped central region of one conductivity type between more heavily doped terminal regions of the same and opposite conductivity type respectively, a plurality of zones of the opposite conductivity type are provided extending from the surface of the terminal region of the one conductivity type towards but not reaching the central zone. The embodiment, Fig. 4, is formed from a weakly doped wafer 2 of N type silicon by successively diffusing boron or aluminium and phosphorus respectively into its opposed faces to form P and N zones 3, 6, masking a number of areas of the N zone arranged in a rectangular matrix, diffusing further phosphorus in to increase the conductivity of the unmasked areas of zone 6, removing the masking, and diffusing in aluminium or gallium to form P zones in the previously masked areas, providing electrodes 9, 10 on the wafer faces, and bevelling and lacquering the edge surfaces. |
