Four point probe geometry modified correction factor for determining resistivity

Development of Flexible Dispense-Printed Electrochemical Immunosensor for Aflatoxin M1 Detection in Milk

“…Characterization of electrical properties: The sheet resistance (R sh ) of the WE prior to spray deposition of SWCNTs was measured with a four-point probe system, using a source meter. It was calculated according to Reference [28] and resulted 4.08 ± 0.06 Ω/□ for unfunctionalized dispense-printed electrode (n = 3), and functionalization increased the R sh to 1.12 ± 0.16 kΩ/□. This increase of R sh was due to the semiconducting nature of the SWCNTs.…”

Open-Source Automated Mapping Four-Point Probe

“…V, I respectively are voltage measured on the inner probes and current through the outer probes. If the thickness of the sample is defined as t, distance between needles of the probe as s, diameter of the sample as d, and distance of the probe to the edge of the sample as x , then Equation (1) is valid only when s/t, d/s, and x /s are sufficiently large and the distance between each needle are equal [ 47 , 48 , 57 , 65 ]. Several similar systems have been developed [ 50 , 55 , 56 ], but none has tried to develop a system that will automatically measure different points on a sample, nor have the designs been disclosed in a digital format as done here for easy and inexpensive replication by other researchers.…”

Investigation of the Use of 3-D Printer Platform as Building Block for Rapid Design of Research and Manufacturing Tool

“…The inline four-point probe configuration is used for the system, with outer probes as the current probe and inner probes as the voltage probe. The system is intended to perform measurement with only one four-point probe configuration and will calculate approximate sheet resistance using equation: the distance between each needle are equal [47], [48], [57], [65]. Several similar systems have been developed [50], [55], [56], but none has tried to develop a system that will automatically measure different points on a sample, nor have the designs been disclosed in a digital format as done here for easy and inexpensive replication by other researchers.…”