| 摘要 |
<p>783,511. Semi-conductor devices. RADIO CORPORATION OF AMERICA. Dec. 23, 1953 [Dec. 31, 1952; March 23, 1953], No. 35757/53. Class 37. In a method of making a semi-conductor device comprising partially diffusing a body of activator material characteristic of one conductivity type into a surface of a larger semiconductor body of the opposite conductivity type to form a PN junction, the activator body is deformed during the melting, causing the diffusion by a contacting member of good heatconducting metal wettable by the activator material with respect to the shape it would have assumed in the absence of the member, whereby the shape of the junction formed is a mirror image of the deformed shape of the surface of the activator element and whereby the member provides a terminal for the device. In the Fig. 3 embodiment discs 10, 12 of activator metal are pressed by metal contacting members 18, 25 against surface regions of Ge wafer 2 which are free from the heat resistant and chemically inert film 4, e.g. of evaporated silica, covering the remainder of the surfaces, the pressure being limited by mica spacers 6, 8. The assembly is heated at 500‹ C. for 10 minutes to diffuse the activator material into the wafer to form parallel PN junctions therein, and to fuse it to members 18, 25. Electrode 16 is simultaneously ohmically connected to the wafer by a blob of tin or solder. Members 18, 25 are provided with tapped holes 28, 30 by means of which metal cooling fins may be attached and the device is encased in plastic 26. One of the members may be a metal cup into which the other elements fit, the other elongated member and ohmic connection being positioned by a lid during the heating. The lid may then be retained or removed and the cup filled with plastic material. A layer of gold is used between each contacting member and its associated activator body to prevent diffusion into the Ge from the members. In a further embodiment (Fig. 6) metal contacting members 48, 50 are provided with curved parallel parts where they contact the activator so as to provide curved parallel junctions.</p> |
