一种基于Guard技术的皮安级电流校准方法  

A current calibration method of pA-level based on Guard technique

作　　者：李灏 郑世棋[1] 乔玉娥[1] 丁立强[1] 梁法国[1] LI Hao;ZHENG Shiqi;QIAO Yu’e;DING Liqiang;LIANG Faguo(The 13th Research Institute,CETC,Shijiazhuang 050051,China)

机构地区：[1]中国电子科技集团公司第十三研究所

出　　处：《中国测试》2019年第11期45-50,共6页China Measurement & Test

摘　　要：针对具有Guard保护端的源表类仪器皮安级电流不易计量的现状,采用取样电阻法的间接测量方案,完成微小电流的有效校准。为解决方案中高源内阻电压精确测量的难题,对源表类仪器广泛采用的Guard保护技术原理进行分析,建立高源内阻电压精确提取模型。研制低电流适配器,组建校准系统,编写自动校准程序,并完成低至1 pA的微小电流校准实验。数据表明:实验结果同上级校准值一致性良好,校准方法能够对具备Guard端口的源表类仪器实现微小电流的有效校准。Considering that pA-level current outputted by source-meter instruments is difficult to metering,an indirect calibration scheme based on sample resistance method was conducted,which achieves effective calibration of micro-current.In order to solve the problem about measuring the voltage on high value resistance,Guard technique which was widely used by source-meter instruments is researched,and exact model to extract the voltage was constituted.A micro-current adaptor was made,calibration system was constructed,automatic calibration program was written,and calibrating experiment of micro-current as low as 1 pA was conducted.Experimental data is coincident with calibrated value given by superior instrument,indicating that this method could realize the micro-current calibration of source-meter instruments with Guard ports efficiently.

关 键 词：源表 微小电流校准 取样电阻 Guard技术 适配器 

分 类 号：TB971[一般工业技术—计量学]