패드컨디셔닝 온도조절이 광역평탄화에 미치는 영향

Abstract

Recently as speed of semiconductor gets higher and integration capacity gets bigger, multi-layer interconnection technique becomes important problem in sub micron process. Especially, decrease of wavelength related to the source of light is necessary to perform minute pattern in the process technique under 0.35㎛. As the wavelength decreases, resolution is improved but depth of focus decreases, which brings unflatize in multi layer process. There are two methods in the conventional process. CMP process is effectively used to flat dielectric layer such as IMD, ILD, PMD and metal layer such as W, Al, Cu in order to perform multi layer structure of deep sub micron integrated circuit. It is also done to make various devices and new materials. As the aluminum wiring materials has been replaced by copper and wiring materials with low-K have been developed, the new process - CMP can flat globally. Since 1980 the method has been used by IBM. Chemical and mechanical process is introduced to get over these technical problems. CMP provides slurry particles whose size is hundreds of Å on the pad of macromolecule material attached to platen. It presses wafer carrier and polish the surface of wafer. Processed material presses elastic pad. Good corroded liquid and micro particle eliminates chemically. In the surface of pad, pressure and temperature gets higher. So chemical and mechanical processing makes flatization processing. ITO-CMP was performed by change of de-ionized water (DIW) temperature in pad conditioning process. DIW with high temperature was employed in pad conditioning immediately before indium tin oxide (ITO) CMP. Removal rate, within-wafer non-uniformity (WIWNU%), and surface morphology of ITO thin film were investigated.