| With the high-speed development of the science and technology, the computers are being updated continuously. At the same time, the capacity of memories is constantly rising. The Integrated Circuits (IC), as the basic components, have been changed from VLSI to ULSI. Graphics are becoming minuter and the dimension of the circuits is shrinking, because of which a very complex circuit is capable of being integrated in a very tiny space in a silicon piece. But this demands that the radius of silicon wafer must grow constantly to improve productivity on the one hand. On the other hand the requirement for the perfection, machine intensity and electronic character of the crystal will become more rigorous. Furthermore the electronic characters and equality of micro-area is fatal to the performance of parts in the future. So the measurement for micro-area resistance rate turns to an important working procedure in the IC making. To ensure the quality of IC and the performance of the production, the four point probe technique must be progressed.This paper mainly accomplished the following research: discussing for the importance of the micro-area resistance measurement, summarizing the characters of the various existing methods, and analyzing the basic principle of four-point probe measurement technique in detail. The paper discussed the measurement technique of traditional four-point probe in a line, modified Van Der Pauw technique and modified Rymaszewski four-point probe technique in emphasis and studied the common problems in various four-point probe techniques and concluded that finite element is applicable for solving the problem of edge revise. In the design of mechanism system, the paper put forward the non-clearance movable plane testing flat project to control the spaces between the micro-areas, with which a better location precision was achieved. The single chip micro-processor system was used to design the circuit for measuring the sheet resistance and the measurement was performed practically.The paper analyzed the influence exerted on the measurement result by probe vacillates during the measurement performance if square four-point probe and four-point probe in a line method were applied. Finally a conclusion was drawn that square four point probe is better than four point probe in a line under the same vacillate. The paper puts forward the projects to overcome the probe vacillate when the square 4-probe method is applied-applying improved Rymaszewski formula to calculate.At present the probes must be adjusted manually during the micro-area resistance measurement, this method wastes a lot of labors and time. To achieve supervising the four point probe adjustment and location in the micro-area by the image identification technique, a procedure was applied to drive the step-run motor to locate the probes automatically, so the measurement procedure was accelerated. The collected probe images were handled by the following: pretreatment, brightness revises straight-square-map rectification, 2-valued and edge-extraction. On the basis of probe image analysis, principle of threshold selection analysis, the paper achieved probe identification, compensation and location to fulfill the automatic probe adjustment and the function of supervision.The main new view points of the research:1. It is the first time for applying image manipulation and analysis technique to the sheet resistance measurement, and achieving the auto-location function of the probe. This is the first time in this field.2. Putting forward improved Rymaszewski formula for solving the probe vacillating in square four point probe measurement and testing project correspond to it. The practical sample is tested.3. Applying non-clearance lognitudinal and transverse measurement flat to achieve the high-precision measurement for large silicon wafer, with the space between equal points and without measurement image.4. Studying the influence exerted on the measurement result by square four point probe and line four point probe vacillate .5.
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