A probing apparatus includes a set of conductors configured to contact a surface of a workpiece simultaneously. A processor activates subsets of the conductors to determine a four-point-probe parameter, wherein the subset is less than the set of conductors. Another subset determines another four-point-probe parameter. The set of conductors remain in contact with the surface of the workpiece during and between activating each subset. A process of forming a probe head includes a probe substrate and associated conductive leads. An insulating layer is formed over the probe substrate and patterned to expose the leads. Conductors, connected to the leads, are formed over the insulating layer and define a probing area of a least 250 cm2.A process of forming an electronic device includes contacting a surface of a workpiece using conductors. Subset of the conductors are activated to determine four-point-probe parameters at different areas of the workpiece.