Research On Micro-areasheet Resistancetest System Of Four-point Prob Technique Based On LabVIEW

In the process of semiconductor manufacturing and production, the resistivity is animportant performance index of detecting the doping concentration of the semiconductor,so testing micro-area sheet resistance became a significant process when processing chips.Four-point probe technique is the most common method for measuring micro-area sheetresistance, which includes abundant theory, has been widely used in semiconductorproduction. With the rapid development of integrated circuit, semiconductor material hasbeen put forward higher requirement, it not only requires design tools, but need reliableoperation, high precision testing method. this paper was based on the four-point probetesting principle, used LabVIEW to build the sheet resistance of system, which canmeasure the Micro-area Sheet Resistance. Solved the traditional low speed, lowmeasurement precision of faults, has high application value. The main contents as follows.First of all, this paper introduced the present development situation of Micro-areaSheet Resistance testing technology at domestic and foreign, then described the basicknowledge of virtual instrument and LabVIEW, summarized the advantages of virtualinstrument compared with traditional instruments, Compared the conventional linearfour-point probe measurement method, Van Der Pauw method, improved Van Der Pauwmethod, diagonal square four point probe method, analysis their respective advantages anddisadvantages. Choose the conventional linear four-point probe method measuringprinciple as the foundation to set up test system.Second, according to the test system should be own quicker response, and canrealize the rapid and accurate measurement, planned the hardware and software of testsystem, in order to make the design more clear, draw the flow chart of technical route andthe overall structure of test system.The hardware part of the test system has carried on the overall design, the hardwareconstants current source circuit, analog channel, amplifying circuit, filter circuit,temperature sensor, data acquisition card and computer. The role of each circuit wasdescribed in the system, and used software to draw the corresponding circuit diagram, thenaccording to the demand of system to choose suitable temperature of the sensor and dataacquisition card.LabVIEW have strong ability of data acquisition and signal processing, software part of this paper is mainly use the software to carry on the design. The software has designedthe system of data acquisition module, data processing module, temperature correctionmodule, data storage module, data reading module of the program.Finally, in order to verify that the system, the feasibility of using RTS-8four-pointtester made comparative experiments with this system, The results show that the four pointprobe method based on LabVIEW sheet resistance test system can test sheet resistancemeasurement, The operation of system is flexible, not only reduces the cost, but improvesthe efficiency.