用高分辨电感耦合等离子体质谱仪检测电子级多晶硅中表面金属杂质的方法

Method for the Detection of Surface Metal Impurities in Electronic-grade Polysilicon by a High Resolution Inductively Coupled Plasma Mass Spectrometer

将多晶硅试样用硝酸、氢氟酸和水的混酸(1:1:10)浸取后,在硝酸介质中,用高分辨电感耦合等离子体质谱仪定量检测电子级多晶硅中表面金属杂质痕量分析方法。对杂质成分Na、K、Fe、Ca等的测定同位素和分辨率的比对研究,优选出最佳参数可显著减少对绝大多数多原子离子以及对电荷分子干扰的影响危害,实现了被测元素与干扰元素的完全分离。标准曲线线性R值>0.999,方法检出限<5ng/L,采用MSA分析Na、K、Ca、Fe元素的测量精确度R&R%<10%。

A method for quantitative determination of trace metal impurities on the surface of electronic grade polysilicon by high resolution inductively coupled plasma mass spectrometry in nitric acid medium after the polysilicon sample was leached with nitric acid, hydrofluoric acid and water mixed acid(1:1:10). Through comparative study on the determination of isotopes and resolution of impurities such as Na, K, Fe, Ca, etc., the optimal parameters can significantly reduce the impact of interference on most polyatomic ions and charge molecules, and achieve complete separation of the measured elements and interfering elements. The linear R value of the standard curve is more than 0.999, the detection limit of the method is less than 5 ng/L. The measurement accuracy of Na, K, Ca, Fe elements by MSA analysis is R&R%<10%.