110 THE BELL SYSTEM TECHNICAL JOURNAL, JANUARY 1952 



,0-10 ,0-9 



10-'^ 10"6 10-5 ,0" 



CURRENT IN AMPERES 



10"3 10-2 



-15 -10 -5 5 10 -15 -10 -5 5 10 

 VOLTAGE 



(d) 



Fig. 3— Characteristic curves, (u) and (c) unbombarded silicon, (b) and (d) 

 silicon bombarded with 30-kv helium ions. 



