随着微电子技术进一步发展,低k介质的引入使得铜的化学机械平坦化（CMP）须在低压下进行。提出了一种新型碱性铜抛光液,其不含常用的腐蚀抑制剂,并研究了其在低压下抛光及平坦化性能。静态条件下,铜的腐蚀速率较低仅为2nm/min。在低压10.34kPa时,铜的平均去除速率可达633.3nm/min,片内非均匀性（WIWNU）为2.44%。平坦化效率较高,8层铜布线平坦化结果表明,60s即可消去约794.6nm的高低差,且抛光后表面粗糙度低（0.178nm）,表面状态好,结果表明此抛光液可用于多层铜布线的平坦化。%Due to the incorporation of Cu/Low-k for copper interconnects fabrication,the Cu chemical mechanical planarization(CMP) is necessary to be performed at a reduced down pressure.In this paper,we have developed an inhibitor free alkaline copper slurry,the dissolution rate results indicate that the slurry has a low etch rate on copper(2nm/min),the polish results reveal that the copper removal rate can be achieved at 633.3nm/min under a low down pressure of 10.34kPa.The planarization efficiency results show that the slurry has a high planarization capability,it can eliminate about 794.6nm step height.Atomic force microscope(AFM) test show that the copper polished by this slurry has a lower roughness(0.178nm).All the results above show that the slurry can be applied in multi-layers copper CMP.
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