Abstract
Owing to lack of the natural resources on Earth gradually, the environmental protection and the efficiency of resource usage become the core concept for the industrial production. In addition to the waste recycling techniques, Green Chemistry further provides the viewpoint of maximizing the usage and transformation efficiency in the energy, materials, time as a fundamental methodology. Therefore, the fields including academic, officials, and industrial circles gradually introduce Green Chemistry in the activities of production and researching. This dissertation was divided into two distinct sections which the first is the synthesis of ZnO nanostructures, and the second is the removal of post-RIE (reactive ion etching) polymer residue by scCO2-assisted oxidative degradation. In the first chapter, the pyrolysis of zinc acetate dihydrate was used to control the growth of ZnO nanoparticles. Then, this technique was combined with a seed-mediated method to synthesize the ZnO nanorods of high aspect ratio (Chapter 3). In addition to avoid using multiple solvents in the traditional hot soup route, the character of crystal structure was also incorporated in the oriented growth of nanorods. This technique could be applied to the materials of similar crystals structures. The second section was focused on the high consumption of water and organic solvent in the cleaning process of semiconductor manufacturing. Especially after the treatment of chlorine plasma etching usually results in the photoresist hard to completely remove by the oxygen plasma ashing. The third chapter introduced scCO2 as a carrier medium to assist the oxidative degradation reagent reaching on the surface of post-RIE polymer residue. The advantage of zero surface tension of scCO2 also improves the biphasic transportation of oxidative reagent between the cosolvent droplet and the polymer residue. In the last chapter, Monte Carlo method was introduced to simulate the possible aggregation and breakage of cosolvent droplets. The surface area of cosolvent droplets was considered as the index for the contact possibility of oxidative reagent and polymer residue. The preliminary results demonstrated the instable cosolvent droplets could be an explanation for the behavior of supercritical fluid and cosolvent in the extraction and reaction. Our work also provides a framework of researching tool in the related unstable biphasic process.