A model based on statistical method and elastic theory is presented to describe the wear mechanism of the silicon wafer surface during chemical-mechanical polishing. This model concerns the effects of applied pressure and relative velocity between the pad and the wafer on the removal rate during polishing and is capable of delineating the role of the mechanical properties of the slurry particles and the films to be polished. The removal rate is dependent on the elastic moduli of slurry particle and polished film. Comparisons with experimental data demonstrate the validity of the model for predicting relative removal rate for various dielectric films.

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In microelectronics, silicon dioxide (SiO2) is widely used as an insulator including the gate dielectric, isolation, and passivation layers. Conventional methods of preparing SiO2 films, such as thermal oxidation or CVD techniques, are subject to several problems, such as thermal stress, dopant redistribution, and material interaction. To solve these problems, we suggest replacing conventional techniques with a room-temperature method that grows an SiO2 film with similar quality.Liquid phase deposition (LPD) is a room-temperature method for SiO2 formation. To date, LPD-oxide films have been obtained by adding either H3BO31-5 or A16 to hydrofluosilicic acid (HzSiF~) solution saturated with silica. In this approach, however, owing to the number of additional parameters, the deposition reaction in LPD is complicated. Moreover, this method does not consider the contamination from the chemicals, but rather merely assumes that such contamination is minimal, the LPD method with H20 addition was first attempted by Yoshitomi et al. ~ According to Ref. 5, the chemical reaction for SiO2 growth in the treatment solution can be represented by the following equilibrium reaction ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 169.230.243.252 Downloaded on 2015-03-18 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 169.230.243.252 Downloaded on 2015-03-18 to IP

The introduction of DRG payment resulted in significantly reduced examination fee, slightly decreased medical costs without significant difference in several detailed items, a reduced number of GA cases without statistical significance, and more patients receiving additional operations. The possible solution to make a profit under the DRG payment scheme is to curtail the costs of radiological images and medication, lower GA percentage, perform fewer additional operations, and correct recording of complications or comorbidities.