Jerry Suran – The Story of the Unijunction Transistor 



Oral History – Jerry Suran (Continued)


At that time the field had pretty well switched from point contact to junction transistors and GE was at the forefront, and maybe a close second to Bell Telephone Laboratories in the development of junction devices.  Part of my job was to understand the performance and characteristics, if not the physics, of transistors.  As a matter of fact, the first article I wrote when I was at GE Electronics Laboratory was received in 1953 by the Journal of Applied Physics. It was entitled “The Effect of a Transverse Electric Field on Carrier Diffusion in the Base Region of a Transistor”.


As a result of this theoretical work on field effects in the base region of transistors, I became interested in the possibility of building a transistor tetrode - taking a cue from simulating the vacuum tube tetrodes, and wondering what would happen if one were to apply a field across the base. The thing that crossed my mind at that time was that maybe we could reduce surface recombination and increase the gain of a transistor. And, if it were at all possible to get the field to act transversely, we could even increase the diffusion speed across the base and improve the gain-bandwidth product by that dual effect. 


At the time you were doing this work, you were using junction transistors? 


We were using junction transistors, and at that time, all of the work was in germanium.  These (devices) were being built in John Saby’s lab in the Electronics Laboratory. 




Oral History – Jerry Suran (Continued)


 That group was just upstairs in the same building. We were the circuits group, under Shea, and Arnie Lesk was in that group, reporting to John Saby.   He was the one I was working with and I asked him if he could maybe build some tetrodes for us to experiment with.  Just try to put two ohmic contacts across the base of a transistor, and try to build the transistor just the way he would normally build a triode.  We were just curious to see how these things would work. 


I believe that this particular experiment was run about a year after I came to the Electronics Laboratory, so it was probably about the middle of 1953, or maybe a little bit later in that year. What happened was that the first couple of tetrodes that we got we could notice very little effect of the electric field.  Our theory just wasn’t born out, that this fourth electrode was going to do anything at all.  On the other hand, one of those tetrodes curiously had a hysteresis effect on the input, and when we put an oscilloscope on it we found that the thing was oscillating.  There was no effect of input voltage or current on the output, so it became apparent quickly that something had happened to the collector contact and that this one had a broken lead.




Go To Suran Oral History, Page 3






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