超高纯三甲基铝（纯度大于7N）中杂质如有机硅化合物、烷基铝氧化物等，其含量约为几个ppm级，甚至是ppb级，这种ppb级含量的杂质难以用常规分析仪器检测。ICP-MS进行无机杂质的检测，方法简单，对不同元素的测定。具有检出限极低ppb级、重现性好，一次分析多种元素等显著特点。三甲基铝样品处理过程：先氧化，再用酸溶解成水溶液，稀释后进行测试，使用ICP-MS仪器进行分析，测量方法参照《电子化学品 电感耦合等离子体质谱法通则》来确保检测纯度的可靠性。针对三甲基铝下游产品处延片及最终的光电器件或高频器件质量产生影响，从而确定了需检测的杂质。最终依据这五种（硅、铜、镁、锌和铁）有害元素含量（相对于基体铝的重量百分比的总量），差量法来判定出三甲基铝的纯度。

Ultra-high purity trimethyl aluminum (purity greater than 7N) impurities such as organosilicon compounds, alkyl aluminum oxides, the content of about several ppm level, or even ppb level, this ppb level of impurities is difficult to detect with conventional analytical instruments. ICP-MS for the detection of inorganic impurities, the method is simple, the determination of different elements. The detection limit is very low ppb, reproducibility is good, and multiple elements are analyzed at one time. Trimethylaluminum sample processing process: firstly oxidized, and then dissolved into aqueous solution with acid, and then tested after dilution. ICP-MS instrument was used for analysis, and the measurement method was in accordance with "General Principles of Electronic Chemical Inductively Coupled Plasma mass Spectrometry" to ensure the reliability of purity detection. In view of the influence of trimethylaluminum downstream products on the quality of wafers and final photoelectric devices or high-frequency devices, the impurities to be detected are determined. Finally, the purity of trimethyl aluminum was determined by the difference method according to the content of five harmful elements (silicon, copper, magnesium, zinc and iron) relative to the total weight percentage of aluminum matrix。.