Details

Autor(en) / Beteiligte

• Mackenzie, David M A
• Kalhauge, Kristoffer G
• Whelan, Patrick R
• Østergaard, Frederik W
• Pasternak, Iwona
• Strupinski, Wlodek
• Bøggild, Peter
• Jepsen, Peter U
• Petersen, Dirch H

Titel

Wafer-scale graphene quality assessment using micro four-point probe mapping

Ist Teil von

• Nanotechnology, 2020-05, Vol.31 (22), p.225709-225709

Ort / Verlag

England: IOP Publishing

Erscheinungsjahr

2020

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Micro four-point probes (M4PP) provide rapid and automated lithography-free transport properties of planar surfaces including two-dimensional materials. We perform sheet conductance wafer maps of graphene directly grown on a 100 mm diameter SiC wafer using a multiplexed seven-point probe with minor additional measurement time compared to a four-point probe. Comparing the results of three subprobes we find that compared to a single-probe result, our measurement yield increases from 72%-84% to 97%. The additional data allows for correlation analysis between adjacent subprobes, that must measure the same values in case the sample is uniform on the scale of the electrode pitch. We observe that the relative difference in measured sheet conductance between two adjacent subprobes increase in the transition between large and low conductance regions. We mapped sheet conductance of graphene as it changed over several weeks. Terahertz time-domain spectroscopy conductivity maps both before and after M4PP mapping showed no significant change due to M4PP measurement, with both methods showing the same qualitative changes over time.