分析了铜多层布线中阻挡层的选取问题，根据铜钽在氧化剂存在的情况下，抛光速率对pH值的不同变化趋势，提出优化碱性抛光液配比进而改变pH值，以达到铜钽抛光一致性的方法，并进行了相应的实验研究。

In this paper, the final polishing slurry and polishing techniques are studied, which is based on the investigation of the polishing kinetics process and mechanism of the silicon substrate. The new polishing kinetics process and mechanism are put forward. CMP final polishing slurry used in silicon substrate polishing is also researched, in which the smaller size (ranging from 15 to 20nm) silica sols is chosen as abrasive instead of large size silica sol (ranging from 50 to 70nm). The polishing slurry with smaller abrasive and polishing technology effectively reduces the roughness and thickness of the damaged layer resulting from abrasion (commonly about one fourth of the abrasive particle size) and also affords high polishing rate (200nm/min). The influence of PH adjustment, abrasive size, temperature and flow of the polishing slurry, are also discussed. During CMP of silicon substrate, chemical action is reinforced. After more research, the main ingredients, including organic-alkali hydroxide multi-amine, surfactant and abrasion are chosen preferentially. In a word, the compositive effect that includes smaller particle abrasion (ranging from 15 to 20nm), high polishing rate (200nm/min), lower damage, easy washing and higher surface degree of finish, are ultimately achieved by this means of the polishing slurry and polishing techniques in this paper. The final polishing slurry and technology effectively resolve the technique problems, including surface scoring, polishing haze, metal ion contamination and residuary particle. Thereby, IC devices and the rate of final products are markedly improved.

In this paper, the cleaning of silicon after CMP (chemical mechanical polishing) in ULSI was studied utilizing preferential adsorption knowledge. On the basis of analyzing adsorption state of contaminated particles on polished silicon wafer and interrelated adsorption theory, the preferential adsorption model is put forward: t=kr2/(f1f2s). Non-ion surfactant is chosen and acts as the second kind of adsorbate, which is preferentially adsorbed onto the polished silicon wafer. The second kind of adsorbate can effectively depress the surface energy of new polished silicon wafer, form a layer of protective film and prevent the chemical adsorption and bonding of the contaminated particle near the surface of polished silicon wafer. In addition, a new kind of chelant, being a free metal ion, is also added in order to chelate and wipe out the metal ion on the polished silicon wafer. Consequently, the organic impurity, impurity particles and metal ion on the silicon surface were wiped out effectively and the silicon has a pure surface after cleaning. The results of cleaning experiments show that the chemical cleaning method in this paper can control the adsorption state of particle on the polished silicon wafer and cause the adsorption state to remain at the physical adsorption state for a long time: even after 168h in the surfactant solution the wafers reach the SEMI standard after being washed.

对甚大规模集成电路（ULSI）多层布线中二氧化硅介质的抛光机理、工艺条件选择、抛光液成分与作用等进行了综合分析，如何使用化学方法提高抛光速率、改善表面状况以及解决金属离子沾污等问题及发展趋势进行了综述，对现存的一些难题提出了改进方案。