| 摘要 |
1,141,918. Semi-conductor devices. MATSUSHITA ELECTRONICS CORP. 29 Nov., 1966 [16 Dec., 1965], No. 53331/66. Heading H1K. A semi-conductor device capable of generating microwave oscillations comprises a germanium junction diode produced in a substrate having an impurity concentration in the range 10<SP>15</SP> to 10<SP>18</SP> atoms. cm<SP>-3</SP>, the oscillation being produced by applying a reverse bias greater than the breakdown voltage. As shown, Fig. 1, an N-type germanium wafer 4, having an impurity concentration within the specified range, is placed on a layer of tin solder 5 and an iron-nickel alloy plate 6. A layer 2 of indium is placed on the other face of wafer 4 and the assembly heated to alloy layer 2 to the wafer to form a P-type layer 3. The device is then electrolytically etched and encapsulated. A plurality of devices may be produced by epitaxially depositing a layer on a substrate of the opposite conductivity type having an impurity concentration within the specified range, applying an electrode to the grown layer by evaporation or soldering and then cutting up the wafer. Suitable diodes may also be produced by diffusion. An encapsulated diode may be mounted in a waveguide (10) provided with impedance matching screws (11) and supplied with a suitable reverse biasing voltage to generate electrical oscillations, Fig. 3 (not shown). The oscillations are stated to comprise a number of overlapping waves, and the critical frequency (i.e. that of the wave having the lowest frequency) increases with increasing impurity concentration of the substrate. |
