This small business innovation research (SBIR) Phase I project proposes the development of a novel abrasive-free recyclable copper CMP (AFCMP) recyclable process based on an unique patented iodine chemistry which leads to the formation of a soft, insoluble copper iodide layer on the surface of the copper. This layer can be gently removed by the polishing pad without the need for particles in the slurry (abrasive-free slurry). This process is in contrast to conventional CMP processes that forms a hard copper oxide layer (by addition of hydrogen peroxide), which require both etching chemicals and hard abrasives (alumina/silica) for removal. In contrast, the copper iodide layer possess nearly an order of magnitude less hardness, thus can be easily removed by the polymer polishing pad. The insoluble copper-iodide in the effluents can be removed by filtration and the chemicals can be recycled back for CMP polishing. This project will attempt successful demonstration of (i) copper polishing using abrasive-free CMP slurries to meet present technical requirements, (ii) compatibility of AFCMP slurries to next generation ultra-low k dielectrics materials, (iii) the ability to filter and obtain consistent performances with the filtrate slurries.
The rapid integration of low k interconnects and AFCMP is expected to lead to substantial profits and energy savings. Environmental friendly manufacturing, and increase in hi-tech jobs. US will be a leader in copper low k CMP technology; and US based semiconductor companies will have a local slurry supplier. Ensure US leadership in nanotechnology.
