OBSERVATION OF NEGATIVE DIFFERENTIAL RESISTANCE PHENOMENON IN A 2-STEP BARRIER DIODE

In this work, the realization of AlxGa1-xAs/GaAs two-step barrier diod e is presented. Experimental observation on the current-voltage charac teristics of the two-step barrier diode is reported. At both room temp erature and 77 K, it shows a strong negative differential resistance u nder forward bias while no similar phenomenon was observed under rever se bias. Such an asymmetric current-voltage characteristic would open the possibility of negative differential resistance in an ac field in the absence of a dc bias. Theoretical simulation and experimental curr ent-voltage characteristics are compared and discussed. (C) 1996 Ameri can Institute of Physics.