Sheet Resistance

The sheet resistance is a measure of resistance of thin films that have a uniform thickness. It is commonly used to evaluate the outcome of semiconductor doping, metal deposition and resistive paste printing. Examples of these processes are: doped semiconductor regions (e.g. silicon or polysilicon), and the resistors which are screen printed onto the substrates of thick film hybrid microcircuits.
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the resistance of a film, material or layer measured by a four point probe. The resistance represents the parallel resistance of an infinite number of infinitely thin parallel sheets. Sheet resistance is expressed as ohms per square area and is equal to the average resistivity of a layer multiplied by the junction depth or thickness of the layer.