Preparation And Structure Of Fluorinated Amorphous Carbon Films Pecvd And Performance

Materials of Fluorinated amorphous hydrogenated carbon thin films (a-C: F: H) with new functions will be used in the electrical and optical field. They have been under investigation for a few years due to their excellent physical properties such as low dielectric constant, low refractive index, low friction coefficients, good gap fill capability, ease to be processed and so on. These films will be used in industrial applications as low dielectric constant interlays in ultra large-scale integration (ULSI) technology. In this paper, a-C: F: H were deposited using radio frequency plasma enhance chemical vapor deposition (RF-PECVD) reactor with CF4 and CH4 as source gases and they were deal with thermal annealing in a N2 environment. The effects on thin films of construct and physics properties by RF-power, deposition temperature and flux ratio were investigated. After studying and analysis, many important conclusions are found. Growth rate of a-C: F: H thin films was mainly determined by deposition temperature and RF-power; low deposition temperature and RF-power were the qualification to gain even and smooth surface a-C: F: H films; stability and surface of thin films become better after annealing heat treatment. The factors affecting component and chemical bands of thin films were RF-power, deposition temperature and flux ratio of the gases. Optical band gap is connected with the content of F and CF; in other words, it relates to the configuration of sp2 in thin films; the moreF and CF the films contains, the less optical band gap. In the course of deposition, the optical band gap is determined by RP-power and flux ratio and deposition temperature. The dielectric constant of these films join to the content of F and the ratio of [CF+CF3]/CF2. The flux ratio of CF4/[CF4+CH4] is primary factor to influence the dielectric constant when thin films deposited; of course, RF-power and temperature contribute to it too. The thermal stability of a-C: F: H films has been found to be strongly dependent on the substrate temperature during deposition and the annealing temperature. Some crystal has been created in thin films due to the high deposition and annealing temperature; to a certain extent, RP-power affects the configuration of the films.