烷基糖苷对硅片化学机械抛光腐蚀缺陷的影响

Effect of Alkyl Polyglycosides on Corrosion Defects in Chemical Mechanical Polishing of Silicon Wafe

针对化学机械抛光(CMP)后硅片表面出现腐蚀缺陷的问题,研究了烷基糖苷(APG)对硅片表面腐蚀缺陷的影响。结果表明APG对硅片的抛光速率和静态腐蚀速率都有抑制效果,当APG质量浓度为0.8 mg/L时能获得较快的抛光速率(836 nm/min)、较低的静态腐蚀速率(3 nm/min)。经过不含APG的抛光液抛光后,硅片表面缺陷数目344个,采用扫描电子显微镜发现缺陷类型主要是腐蚀缺陷,此时硅片表面粗糙度0.58 nm。当抛光液中加入0.8 mg/L的APG时,缺陷数目下降到43个,表面粗糙度下降到0.28 nm。接触角和Langmuir吸附计算结果证明,APG主要依靠其亲水端的羟基和醚键在硅片表面物理吸附成膜,从而隔绝了抛光液中有机碱对硅片表面的腐蚀。

To the problem of corrosion defects on the surface of silicon wafer after chemical mechanical polishing(CMP),the effect of alkyl polyglycosides(APGs)on the corrosion defects on the surface of silicon wafers was investigated.The results indicate that APG has inhibitory effects on the polishing rate and static corrosion rate of silicon wafers.When the APG mass concentration is 0.8 mg/L,a faster polishing rate(836 nm/min)and a lower static corrosion rate(3 nm/min)are obtained.After polishing with the polishing solution without APG,the number of defects on the silicon wafer surface is 344.The scanning electron microscope shows that the main type of defects is corrosion defects.At this time,the surface roughness of the silicon wafer is 0.58 nm.When 0.8 mg/L of APG is added to the polishing solution,the number of defects decreases to 43 and the surface roughness decreases to 0.28 nm.The contact angle and Langmuir adsorption calculation results prove that APG mainly relies on the physical adsorption of its hydrophilic hydroxyl and ether bonds on the surface of silicon wafers to form a film,thereby isolating the corrosion of organic bases in the polishing solution on the surface of silicon wafers.