|Title||Direct contact four-point probe characterization of Si microwire absorbers for artificial photosynthesis|
|Publication Type||Journal Article|
|Year of Publication||2016|
|Authors||Engel, J.. T., B.. E. Blaikie, A.. Kumar, A.. Castañeda, A.. Gupta, and D.. R. Oliver|
|Keywords||4-point-probing, electrical-characterization, electrical-contact, electrical-probing, microwires|
We present a facile approach that achieves four-point electrical characterization of silicon microwires fabricated using a bottom-up vapour–liquid–solid process. Tungsten probes are brought into direct contact with silicon microwires using piezoelectrically driven probe actuators. This technique can be applied to silicon microwires without the need for high-temperature lithographic preparation or the additional use of In/Ga to ensure reliable electrical contact between the probe and the wire. Comparison between two-point probe and four-point probe measurements demonstrates the robustness of the four-point approach. Significantly, the four-point characterization technique is not impacted by native oxides at the microwire/tungsten probe interface. The four-point technique can be applied to sense electrical responses in half-cell and full-cell representations of artificial photosynthesis systems, regardless of catalysts or functional groups attached to the microwire sidewalls.