摘要 |
965,671. Transistors. RADIO CORPORATION OF AMERICA. March 8, 1961 [March 22, 1960], No. 8516/61. Heading H1K. [Also in Division H3] A transistor for use in a frequency converter (see Division H3) has two emitters 43, 44 sideby-side, one being used for signal and a.g.c. purposes and one for generation of the local oscillation. The two emitters are alloyed on to one side of the base and the collector on to the other, the latter encompassing the two emitters so as to collect all injected carriers from both emitters. The base is a diffused N-type region with the impurity at a maximum at the emitters and decreasing to a constant value near the collector junction. To prevent interaction between the emitter circuits a portion of the area between the emitters is etched through to a less concentrated impurity region of higher resistivity and it is stated that one emitter junction may be biased to cut-off without affecting the current in the other. |