Understanding Trap-Induced Barrier Height Fluctuations in Nickel-Silicon Contacts for Advanced Semiconductor Technology

In this work, we present a novel investigation of the Random Telegraphic Noise (RTN) signal in nickel-silicon contacts with and without the interfacial oxide layer, marking the first instance of such an analysis. The observed multilevel RTN signal has revealed the existence of two distinct traps in both scenarios. Specifically, our analysis has unveiled that in the case of an interfacial oxide layer, one of the traps is located near the interface, resulting in barrier height fluctuations of up to 11.5 %. Meanwhile, the other trap situated away from the interface, yields barrier height fluctuations of up to 7.3 %. In situations where the interfacial layer is absent, we report barrier height fluctuations of up to 9.2 % attributed to the first trap and up to 6.0 % due to the second trap, shedding light on the critical influence of the interfacial oxide layer on these fluctuations.