目的 去除因高温烧结而引起的绝缘子表面石墨污染，保障电镀产品的表面质量，探究大气压等离子体清洗代替传统化学/物理去除石墨污染的机理与方法。方法 参照绝缘子污染情况试制石墨污染的4J29金属块样品，分别开展加热Ar+O2、不加热Ar/Ar+O2等离子体清洗对比实验。采用光谱仪分析Ar/Ar+O2等离子体的化学特性。利用电子分析天平、扫描电子显微镜、能谱仪分别检测了样品表面石墨的质量变化、形貌以及元素成分变化。结果 在样品加热的情况下，经Ar+O2等离子体清洗后，4J29金属块表面的碳含量(质量分数)从97%降低至6%;Ar/Ar+O2等离子体均可以在接近常温下有效去除石墨，且Ar+O2等离子体的石墨去除效率较纯Ar等离子体提高0.7倍;在样品加热到300 ℃情况下，Ar+O2等离子体的石墨去除效率较不加热时提高了27.3倍。结论 大气压Ar+O2等离子体清洗可以有效去除电镀零件表面的石墨污染;石墨去除效率与活性氧原子密度呈正相关;提高零件表面温度可以在活性氧原子供应充足的情况下显著提高石墨去除效率。

Insulators are sealing components used in microelectronic packaging to provide insulation support and connect internal and external circuits. They are widely used in metal packaging of integrated circuits and discrete devices.Subsequent to the process of high-temperature sintering, surfaces of glass insulators will be contaminated with graphite. Despite of extensive remediation efforts involving multiple rounds of chemical cleaning and physical brushing, the eradication of this contamination remains challenging. The persistence of residual graphite post-cleaning procedures poses a significant risk, contributing to defects in the subsequent electroplating process.Atmospheric pressure microwave plasma cleaning has been studied as a replacement for chemical cleaning to improve the electroplating quality of insulator components. 4J29 metal blocks, which simulate the contamination situation of insulators, are used as samples to study the graphite removal effect of plasma. Graphite carbon sheets are used as samples to study the efficiency of graphite removal. Ar+O2 plasma is used to clean the 4J29 samples under both heated and non-heated conditions. The changes in the microscopic morphology and elemental composition of the sample surface are studied to understand the removal effect of adhered and embedded graphite on the metal surface. Further, the working gas and sample temperature are adjusted for plasma cleaning experiments. The chemical characteristics of the plasma are analyzed by a spectrometer, and the mass change of the graphite carbon sheet is detected by an electronic analytical balance. The effect of oxygen and temperature on the graphite removal by plasma is investigated. After the Ar+O2 plasma cleaning with sample heating, the carbon content on the surface of the 4J29 metal block decreases from 97% to 6%. Both Ar/Ar+O2 plasma can remove graphite under near room temperature, and the graphite removal efficiency of Ar+O2 plasma is twice that of Ar plasma. Graphite in the air does not decompose naturally at a temperature of 330 ℃, but after heating to 300 ℃, the graphite removal efficiency of Ar+O2 plasma is 27.3 times higher than that under no heating. Atmospheric pressure Ar+O2 plasma cleaning can remove the adhered and embedded graphite on the surface of 4J29 metal and reduce the carbon element content on the surface. Plasma cleaning under the condition of alcohol lamp heating can further reduce the carbon element content on the surface. After 10 min of plasma cleaning with heating, there is no graphite residue on the surface of the 4J29 metal, and the remaining gray traces are caused by microscopic trap light structures. The density of active oxygen atoms in the plasma is positively correlated with the graphite removal efficiency. In the process of Ar+O2 plasma removal of graphite, desorption is the decisive step. Increasing the surface temperature of the part can significantly improve the efficiency of graphite removal under sufficient supply of active oxygen atoms. Therefore, the process of combining sample heating with plasma cleaning is expected to meet the requirements of efficient cleaning of electroplated parts.