| 摘要 |
1,076,371. Semi-conductor devices. MOTOROLA Inc. Jan. 11, 1965 [Jan. 27, 1964], No. 1233/65. Heading H1K. The avalanche breakdown voltage of a PN junction between a surface region and an underlying region of a semi-conductor body is increased by surrounding the surface region with a further region or regions of the same conductivity type spaced from but within the space charge region of the junction at its breakdown voltage. In a typical diode device the surface region is circular and the further region or regions annular and concentric or eccentric with respect to it and preferably formed in the same diffusion process through oxide masking. This subsequently functions as a passivating layer. Alternatively the region is square or rectangular and the further regions square or rectangular frames. A planar transistor is made on a high resistivity layer epitaxially grown on a heavily doped collector substrate in the same way by diffusion, the emitter region being formed within the surface region in a further diffusion step. In operation the further regions, which may also be formed by alloying or epitaxial deposition, are left floating. |
