基于LabVIEW平台和GPIB接口的GMR效应测量系统

GMR Effects Measurement System Based on Lab VIEW Station and GPIB Interface

介绍了薄膜磁电阻率的自动测试方法。试验中采用了带GPIB接口的电源提供通过薄膜的稳恒电流,用带GPIB接口的纳伏表测量薄膜上的电压降,而作用于薄膜的磁场则通过带GPIB接口的可编程直流电源提供给亥姆霍兹线圈的电流大小来控制。通过LabVIEW平台控制可编程直流源可以控制磁场的变化快慢和幅度,同时利用该平台中的X-Y波形记录控件实时地显示磁场与电阻率变化的曲线。通过对一个已知磁电阻率的样品进行测量,表明结果正确,具有较好的重复性,较高的精度,符合测量要求。

The automatic measurement of the resistivity of thin films is introduced in this article. In the test, the sourcemeter and nanovoltmeter with GPIB interface were used to supply continuous current to thin films and measure voltage, respectively, And the magnetic field applied on thin films is controlled by linear programmable power supply which supplies current to Helmhoitz coil. Utilizing the LabVIEW station to control the linear programmable power supply, the magnitude and changing rate of magnetic field can be controlled. At the same time, utilizing the X-Y graph of the LabVIEW station, the curve of the magnetic field and resistivity change can be obtained. Measuring of a sample of given resistivity shows a excellent agreement. The result meets the requirement of measurement with high precision and repetitiveness,