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Abstract Carbon doped two-dimensional (2D) hexagonal boron nitride nanosheets (BNNSs) are obtained through a CO 2 —pulsed laser deposition (CO 2 —PLD) technique on silicon dioxide (SiO 2 ) or molybdenum (Mo) substrates, showing - stable hysteresis characteristics over a wide range of temperatures, which makes them a promising candidate for materials based on non-volatile memory devices. This innovative material with electronic properties of n-type characterized in the form of back-to-back Schottky diodes appears to have special features that can enhance the device performance and data retention due to its functional properties, thermal-mechanical stability, and its relation with resistive switching phenomena. It can also be used to eliminate sneak current in resistive random-access memory devices in a crossbar array. In this sense constitutes a good alternative to design two series of resistance-switching Schottky barrier models in the gold/BNNS/gold and gold/BNNS/molybdenum structures; thus, symmetrical and non-symmetrical characteristics are shown at low and high bias voltages as indicated by the electrical current-voltage (I–V) curves. On the one hand, the charge recombination caused by thermionic emission does not significantly change the rectification characteristics of the diode, only its hysteresis properties change due to the increase in external voltage in the Schottky junctions. The addition of carbon to BNNSs creates boron vacancies that exhibit partially ionic character, which also helps to enhance its electrical properties at the metal-BNNS-metal interface.
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Low voltage cold and hot switching in nanoswitches cleaned by in situ oxygen plasma can achieve low stable contact resistance
Reliable nanoswitch operation requires low contact voltages and stable electrical contact resistance (ECR). Surface cleanliness is crucial to prevent nanomechanical switch failure, which can occur due to the presence of insulating adventitious hydrocarbon films. In situ O2 plasma cleaning is effective but oxidizes metal surfaces. Here, the noble metal Pt, which forms PtOx, is employed to form electrodes. Previous studies report on PtOx electrical resistivity, but the effects of PtOx evolution at contacting interfaces due to electrical and mechanical stimuli have not been explored. This study investigates the impact of PtOx on ECR at low contact voltages under hot switching, cold switching, and mechanical cycling conditions. An increase in ECR upon plasma cleaning indicates the presence of a resistive PtOx layer. After hot and cold switch cycling at applied voltages of 300 mV or less, a low stable ECR is achieved. A higher contact voltage accelerates ECR stabilization. The results are consistent with PtOx film volatilization, which is primarily due to Joule heating rather than mechanical rupture. This investigation advances the understanding of interface evolution in plasma-cleaned nanoswitches.
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- Award ID(s):
- 1854702
- PAR ID:
- 10593821
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Journal of Applied Physics
- Volume:
- 135
- Issue:
- 2
- ISSN:
- 0021-8979
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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