Lower Temperature Deposition And Characteristic Study On Theβ-SiC Thin Films

Featured by wide band gap, high breakage electric field, high electron mobility, low dielectric constant, strong irradiation proof and excellent chemical stability, silicon carbide (SiC), viewed as one of the most promising wide band gap semiconductors, is widely utilized in optoelectronic devices, high frequency and large power, high temperature electronic devices. However, the ranges of its applications were seriously hindered because of high temperature for preparation. Hence, low temperature growth of high quality silicon carbide (SiC) film, which is advantageous to effectively solve perplexed problems existing in the film such as the self-compensation, intrinsic stress and impurity, plays a critical leading role on applications of SiC film, especially the application on microelectronic devices. Consequently, synthesis of high quality SiC film at low substrate temperature (TSUb) is on hot pursuit as an important study.In this study, high quality cubic SiC (P-SiC) films under optimized condition parameters, corresponding to characteristics of different synthesis methods, were acquired on low temperature silicon (100) wafers using plasma enhanced chemical vapor deposition (PECVD), catalytic chemical vapor deposition (Cat-CVD) and RF magnetron sputtering techniques, respectively. The mechanism for low temperature growth of SiC film was basically displayed on the base of well investigations in the dependence of condition parameters on the structure, component and surface morphology of SiC film, which pave the road for framing up the low temperature growth model. The field emission characteristic of p-SiC film were further studied.p-SiC film was obtained using self designed PECVD system at an ever reported lowest Tsub of 300癈. The solution to the problem of hydrogen contained in the film was initially proposed for PECVD technique. Meanwhile, the adoption of substrate bias assisted deposition further eliminated the impurity O in the film.P-SiC film was acquired, only with the aid of the catalyst's thermal radiation, utilizing self designed Cat-CVD system at an actual temperature below SOOT of the substrate unheated. Hence, not only did this progress extend new synthesis techniques, but also promoted low temperature CVD synthesis of P-SiC film to a new stage. Moreover, high quality nanocrystalline P-SiC film was attained with the integration of the pre-carbonization process and the substrate bias effect.The study on low temperature PVD deposited SiC film was carried out-m-employing bias assisted magnetron sputtering. Furthermore, PVD deposited SiC film mainly containing cubic phase was achieved at room temperature for .the first time. Nanocrystalline SiC film was synthesized at a Tsub of 450癈, nearly approaching the lowest temperature of 450癈 ever reported on sputtered P-SiC film.The roles that the hydrogen and the substrate negative bias play in the low temperature deposition of p-SiC film were further well investigated. It was found that proper hydrogen concentration in gas flows and the corresponding substrate bias are the prerequisite for low temperature synthesis of p-SiC film.The excellent field emission characteristic of the low temperature grown P-SiC film was experimentally and theoretically pursued with well result.In the end, the application prospects of research achievements based on the conclusion on this work was promisingly envisioned.