The GB/T 14141-2009 standard specifies a method for the measurement of sheet resistance of silicon epitaxial layers, diffusion layers and ion implanted layers using the straight row four-probe method. The standard applies to the measurement of the resistance of thin layers on silicon wafers larger than 15.9 mm in diameter, with a thickness of not less than 0.2 µm and a block resistance Measurement range of 10 Ω to 5000 Ω. The method calculates the resistance by applying a DC current to the specimen and measuring the potential difference between probes. The standard also indicates possible interfering factors such as probe material, silicon wafer geometry, environmental conditions, etc., which may affect Measurement accuracy. This method is suitable for the resistance measurement of different conductive types of silicon wafers.