将下列英文文段翻译为中文 . Wafer fabrication 1.Oxidation Oxidation is the progress of growing silicon dioxide or silicon nitride on silicon, as shown in Fig  6-10, silicon is consumed as the silicon dioxide or the silicon nitride are grown. Growth of silicon dioxide occurs in oxygen at 800 °C -1200 °C . Oxidation can prevent O2 diffusion.  2.Photo lithographic Photo lithgraphic as shown in Fig 6-11  The process of photolithography:  Coating  Soft bake  Exposure  Post exposure bake  Develop  Hard bake  Develop check  3.Etch  Etch is the method of removing the materials on silicon. The method of etch can be classified as wet etching and dry etching. Isotropic etchants etch at the same rate in every direction, and anisotropic etchants etch at different rates in every direction, as shown in Fig  6-12. Selectivity is the ratio of the rate of the target material being etched to the etch rate of other materials. Chemical etches are generally more selective than plasma etches.  4.Diffusion and Ion Implant  Doping is the method of importing impurity in silicon to change its electric performance. We can realize it by diffusion or ion implant