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BELL'JYSTEM2TECHNICAL JOURNAL 



2 4 6 8 10 12 14 16 16 20 22 24 



S/lJ/3 X10-2 



Fig. 10— The factor g (Fig. 9) plotted as a function of j//c'", with ^ in cm. and h in 

 amps. 



tor voltage, Vr, is fixed at —15 volts. Curves are shown for /, = —3, 

 — 4, —6, and —8 ma. We may define a geometrical factor, g, as the ratio 

 of /« extrapolated to zero spacing to the value of le at the separation s: 



g(s) = (/e(0)/7e(^)) V,./,=const. (2.18) 



It is to be expected that g{s) will depend on /,, as it is the collector current 

 which provides the field which draws the holes into the collector. For the 



