Establishment of a Four Probe Method for Measuring Surface Resistance of Materials

Surface resistance is an important electrical property of materials, which can characterize the doping of materials, indirectly calculate the carrier mobility of semiconductor materials, and then affect the operating frequency of devices. Accurate measurement of surface resistance is an important link in the process of material production, which is directly related to the quality of material production. Four probe measurement method is the most frequently used measurement method. Although this method is not the most advanced, it is widely used because of its simple and mature. The maximum current of four probe measuring devices on the market is usually 100 mA which can not meet the requirement of measuring the surface resistance of low resistance materials. In this paper, the external current source is used to expand the current range to 3A, and the automatic test software is developed based on Lab VIEW platform, which can meet the surface resistance test of low resistance materials and solve the problem of small current range of traditional measuring equipment.