低压力Cu布线CMP速率的研究  

Study on CMP Rate of Copper at Reduced Down Pressure

作　　者：刘海晓[1] 刘玉岭[1] 刘效岩[1] 李晖[1] 王辰伟[1] 

机构地区：[1]河北工业大学微电子研究所,天津300130

出　　处：《半导体技术》2010年第8期761-763,767,共4页Semiconductor Technology

基　　金：国家中长期科技发展规划02科技重大专项(2009ZX02308)

摘　　要：采用低介电常数材料(低k介质)作为Cu布线中的介质层,已经成为集成电路技术发展的必然趋势。由于低k介质的低耐压性,加工的机械强度必须降低,这对传统化学机械抛光(CMP)工艺提出了挑战。通过对CMP过程的机理分析,提出了影响低机械强度下Cu布线CMP速率的主要因素,详细分析了CMP过程中磨料体积分数、氧化剂体积分数、FA/O螯合剂体积分数等参数对去除速率的影响。在4.33 kPa的低压下通过实验得出,在磨料体积分数为20%,氧化剂体积分数为3%,FA/O螯合剂体积分数为1.5%时可以获得最佳的去除速率及良好的速率一致性。The dielectric layer with low dielectric constant material（low-k dielectric）in copper wiring has become the inevitable developing trend of IC technology.Due to low compression resistance of low-k material,the mechcanical strength must be reduced,which is a challenge for the traditional chemical-mechanical polishing（CMP）technology.Based on the mechanism of CMP process,the main factors of low mechanical copper wiring CMP are proposed.The impacts of abrasive volume fraction,oxidant volume fraction,chelating agent volume fraction on the removal rate have been analyzed in detail.Then,the best removal rate and rate consistency are obtained by experiments under special conditions：low pressure of 4.33 kPa,the abrasive volume fraction of 20%,oxidant volume fraction of 3% and chelating agent volume fraction of 1.5%.

关 键 词：化学机械抛光 铜布线 低机械强度 抛光速率 

分 类 号：TN405.97[电子电信—微电子学与固体电子学] TN305.2