SBIR Phase I: Chemically Impregnated Nanoparticles for Use in Copper Chemical Mechanical Planarization Slurry

这个小企业创新研究第一阶段项目的重点是开发一种含有化学浸渍纳米颗粒的铜化学机械刨平（CMP）浆料。CMP工艺包括抛光垫和含有化学物质和磨料纳米颗粒的水浆。要平化的晶圆表面对着抛光垫旋转，抛光垫不断地提供浆液。机械磨损和化学蚀刻的协同结合创造了高材料去除率（MRR）和快速平化。目前，铜CMP浆液溶液需要一种络合剂，如甘氨酸，以保持足够的MRR，同时也会导致晶圆表面的静态蚀刻和溶解（即腐蚀），这是难以控制的。如果可以控制络合剂对铜表面的暴露，使其仅影响磨损区域，则可以减少或消除静态蚀刻和溶解。因此，本提案的重点是通过将络合剂结合到磨料纳米颗粒中，显著改进铜CMP浆料工艺，使浆料的机械和化学作用局部化、同步化，从而提高加工效率和公差。该项目的更广泛的影响/商业潜力包括推进最先进的CMP浆料配方，并为CMP浆料市场的功能化纳米颗粒打开大门。该项目对铜CMP浆体技术的具体影响包括：通过减少静态蚀刻来提高平化效率（台阶高度减少与去除层厚度之比），消除目前铜CMP浆体中需要的大部分化学添加剂，通过提高分散稳定性来减少颗粒团聚。这些优点最终将导致CMP加工成本的降低，同时也提高了加工公差。此外，利用功能化纳米颗粒改善CMP浆料存在着巨大的机会。该产品的成功实施肯定会导致其他CMP工艺的衍生技术。

This Small Business Innovation Research Phase I project is focused on the development of a copper chemical mechanical planarization (CMP) slurry containing chemically impregnated nanoparticles. The CMP process consists of a polishing pad and an aqueous slurry containing chemicals and abrasive nanoparticles. The wafer surface to be planarized is rotated against the polishing pad which is continuously supplied with slurry. The synergistic combination of mechanical abrasion and chemical etching creates high material removal rates (MRR) and rapid planarization. Currently, copper CMP slurry solutions require a complexing agent, such as glycine, to maintain an adequate MRR, which at the same time, also causes static etching and dissolution (i.e. corrosion) of the wafer surface which is difficult to control. If the exposure of the complexing agent to the copper surface could be controlled so that only the abraded areas were affected, then static etching and dissolution could be reduced or eliminated. Therefore, the focus of this proposal is to significantly improve copper CMP slurry technology by combining the complexing agent into the abrasive nanoparticle, so that mechanical and chemical actions of the slurry are localized and simultaneous, thus improving processing efficiency and tolerances.The broader impact/commercial potential of this project includes advancing the state-of-the-art in CMP slurry formulation and opening the door for functionalized nanoparticles in the CMP slurry market. Specific impacts of the proposed project on copper CMP slurry technology include: increasing planarization efficiency (ratio of step height reduction and removed layer thickness) by decreasing static etching, eliminating a majority of the chemical additives that are currently required in copper CMP slurries, and reducing particle agglomeration by improving the dispersion stability. These advantages will ultimately lead to a reduction in the cost of CMP processing while also improving processing tolerances. Additionally, an enormous opportunity exists to exploit functionalized nanoparticles to improve CMP slurries. Successful implementation of this product will most certainly lead to derivative technologies for other CMP processes.