Operation of poly emitter bipolar npn and p-channel JFETs near liquid helium (10 K) temperature

Abstract

Operation of poly bipolar npn and p-channel JFET transistors is described up to 10 K. Current gain of the npn transistor equal to 3 is measured at 9 K. Transconductance of the p-channel JFET remains constant for 60 K>T>10 K. Certain new phenomena are observed in both the devices below 60 K which are attributed to carrier freezeout and high-level injection. These experimental results also tend to suggest that the useful range of operation of these devices can be extended to below liquid nitrogen temperature.<>