| 摘要 |
1482585 Semi-conductor devices SEMIKRON GES EUR GLEICHRICHTERBAU UND ELEKTRONIK mbH 5 Aug 1974 [8 Aug 1973] 34367/74 Heading H1K At least the peripheral part of a PN junction formed in a lightly doped wafer of one conductivity type is produced by diffusion into the walls of a recess formed in a main face of the wafer, the inclination of the upper edge of the recess and its distance from the eventual location of the wafer edge being such that the junction periphery makes an angle of less than 90 degrees with said edge which itself is normal to the main face of the wafer. In making the thyristor shown in Fig. 4 the junctions between P+ zones 2, 4 and the N-type wafer 1 are identically formed in this way and the emitter region 5 in a subsequent step. A number of device forms may be produced in a common wafer from which they are later divided by use of various circular and annular recess configurations and masking to limit the areas into which diffusion may occur. |
