Development of Silicon Carbide (SiC) Thin Film Preparation Process by Pulsed Laser Deposition' Method

碳化硅（SiC）是具有高热稳定性、优异的耐化学侵蚀性、高热导率、高击穿电子迁移率和高电场的宽带隙半导体。这些特性有利于这种材料在电子和光电器件中的应用。多晶SiC薄膜可以制成蓝光发光二极管和大功率器件。因此，人们采用化学气相沉积、溅射、激光烧蚀、蒸发、分子束外延和碳离子注入等方法在Si（100）衬底上制备了SiC薄膜。激光束聚焦在SiC靶上。在18000个重复频率为10 Hz的激光脉冲之后，完成沉积过程。所有样品均通过场发射扫描电子显微镜（ ...更多信息 FE-SEM）、俄歇电子能谱（AES）、原子力显微镜（AFM）、掠射角X射线衍射（GXRD）、能量色散X射线分析仪（EDX）、傅里叶变换红外光谱（FT-IR）。光学多通道分析仪（OMA）与1024光电二极管阵列检测的光发射从脉冲Nd：YAG激光照射产生的等离子体羽。Si/C组分比受衬底偏压和甲烷气体压力的影响。FT-IR测量表明存在Si-C键拉伸。FE-SEM观察表明，PLD法制备的薄膜表面光滑，无针孔。用GXRD表征了所制备薄膜的结晶度，其随衬底温度的升高和甲烷气体压力的降低而增加。横向磁场可以控制等离子体羽流的形状。采用PLD法制备了CrC、WC、SiC、TiC、CBN、SiN、TaN等硬质薄膜和SnOs、WOa等气敏薄膜。实验结果表明，该工艺是一种简单、有效的制备大面积、高质量、无氮化物、碳化物、氧化物等液滴的陶瓷薄膜的技术。这对PLD工艺的科学化和工业化具有重要意义。少

Silicon carbide (SiC) is a wide-band-gap semiconductor with high thermal stability, excellent resistance to chemical attack, high thermal conductivity, high breakdown electron mobility, and high electric field. These properties favor this material for applications of electronic and optoelectronic devices. Polycrystalline SiC films can be fabricated as blue-emitting diodes and as high power devices. Therefore, SiC films have been fabricated on Si(lOO) substrates by using several methods, including chemical vapor deposition, sputtering, laser ablation, evaporation, molecular beam epitaxy and carbon-ion implantation.In this study, we develop a new pulsed laser deposition (PLD) method with a cross-magnetic field, ion-beam source and a DC bias to synthesize crystalline SiC films. The laser beam was focused on the SiC targets. After 18000 laser pulses at a 10 Hz repetition rate, the deposition process was completed. All samples were analyzed by a field-emission scanning electron microscopy ( … More FE-SEM), Auger electron spectroscopy (AES), atomic force microscope (AFM), glancing-angle X-ray Diffraction (GXRD), an energy-dispersive X-ray analyzer (EDX), Fourier transform infrared spectroscopy (FT-IR). An optical multichannel analyzer (OMA) with a 1024 photodiode array detected the optical emissions from the plasma plume generated by the pulsed Nd : YAG laser irradiation. The Si/C composition ratio is affected by the substrate bias voltage and methane gas pressure. FT-IR measurement indicates the presence of a Si-C bond stretching. FE-SEM observation shows that the surface of the film prepared using PLD is smooth and pinhole-free. The degree of crystallinity of the prepared films, characterized by GXRD, increases with increasing substrate temperature and decreasing methane gas pressure. Cross magnetic field can control the shape of the plasma plume. We prepared CrC, WC, SiC, TiC, CBN, SiN, TaN films as a hard material and SnOs, WOa films as a gas sensor material by PLD method. Our experiments show that our new PLD process is simple and effective technique to fabricate high-quality and large-area uniform ceramic thin films without droplets such as nitride, carbide and oxide films. It might be very important to study PLD process scientifically and industrially. Less