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THE BELL SYSTEM TECHNICAL JOURNAL, JULY 1956 



and the junction resistance limits the magnitude of the drift field that 

 can be set up near the point. For example, if the lifetime t„ of electrons 

 in the p-layer^ is substantially lower than Tp , that of holes in the ger- 

 manium bulk, the reverse current density across the junction can be 

 increased by an increase in Up , and junction resistance lowered. 



Pfann reports a substantial mcrease in the reverse current of formed 

 point contacts with donor concentration of the point wire. The increase 

 in rip will depend on the distribution of donors in the p-layer after the 

 forming pulse. A high donor concentration near the collector point may 



-V, 



(r) 



(b) 

 Fig. 1 — Formed point contact under reverse bias — schematic representation. 



