
A four point probe is typically used to measure the sheet resistance of a thin layer or substrate in units of ohms per square by forcing current through two outer probes and reading the voltage across the two inner probes. A four point probe is typically used to measure the sheet resistance of a thin layer or substrate in units of ohms per square by forcing current through two outer probes and reading the voltage across the two inner probes. Please drop a message to chat about science or measurements.