采用静态膨胀法校准标准漏孔极小漏率的不确定度评定

摘要

An extremely low leak rate calibration method based on static expansion technique has been used to calibrate a vacuum leak of 10-10 Pa· m3/s.It was found the measurement uncertainty mainly comes from the rise rate of ion current a-bout the leakage.Compared with the uncertainty components of three stages expansion method with high purity gases, two stages expansion method with gas mixture can ameliorate the calibration results by avoiding complex expansion process, which simplified the calibration process and improved the calibration efficiency also.%采用静态膨胀法校准10-10 Pa· m3/s量级的真空标准漏孔，通过对校准结果的不确定度评定，发现被校漏率产生的离子流上升率是不确定度的主要来源。与高纯气体三级膨胀的测量不确定度分量相比较，采用混合气体二级膨胀的校准方式，能够减小膨胀过程对校准结果的影响，在简化了校准过程的同时，也提高了校准效率。