| 摘要 |
1,079,197. Semi-conductor diodes. SIEMENS-SCHUCKERTWERKE A.G. June 27, 1966 [June 25, 1965], No. 28786/66. Heading H1K. A monocrystalline semi-conductor wafer containing a PN junction 4 has one major face completely covered by a first electrode 5 of which the outer face is covered by a first contact plate 6, a central region of the other major face being covered by a second electrode 7 which is of smaller area than the first and which has a second contact plate 8 thereon; the inner face of this second contact plate 8 is larger than the outer face of the smaller electrode 7 (with which it is in contact) and extends beyond it all round its periphery through less than 1 mm., whereas the PN junction 4 emerges at the surface of the wafer in a line which is nowhere less than 1 mm. from the smaller electrode 7. A channel (10, Fig. 2) surrounding the smaller electrode 7 may be etched or sand-blasted in the wafer to a sufficient depth to cut through the PN junction 4, and the wafer and/or the second contact plate 8 may be bevelled at the edge so that the face in contact with the smaller electrode 7 is smaller than the face remote from it (Fig. 3). Those parts of the surface of the wafer not covered by the electrodes are coated with a lacquer 9. |
