Chemical Vapor Deposition Processes to Prepare Silicon Nitride Films from Organic Silicon Materials Containing Nitrogen

氮化硅和氮化硅碳薄膜具有优良的性能，如耐磨性、化学惰性、透明性和绝缘性。采用催化化学气相沉积（Cat-CVD）技术，以SiH_4和NH_3为原料，可以制备出器件质量的氮化硅薄膜。可以涂覆有机材料，例如有机发光二极管和用于封装的塑料膜。问题是SiH_4是一种高爆炸性材料，人们期待着替代材料的出现。六甲基二硅氮烷（HMDS）是一种极具吸引力的取代SiH_4的材料。本研究以HMDS和三二甲氨基硅烷的Cat-CVD过程为研究对象，采用电子轰击四极杆质谱、真空紫外光电离飞行时间质谱和离子附着四极杆质谱三种质谱技术进行气相诊断。结合这些质谱测量的结果， ...更多信息 揭示了Si-N键被选择性地断裂，尽管它们比Si-C键更强。N原子的孤对电子可以与催化剂相互作用，选择性地破坏键。必须存在空间位阻以破坏Si-C键。HMDS的加入使NH_3的分解效率显著降低。这表明HMDS对催化剂表面具有毒化作用，阻碍了NH_3的分解。远程催化化学气相沉积技术是解决这一问题的技术之一。该技术利用NH_3或H_2在催化剂表面分解，产生的自由基被转移到下游，在下游引入有机硅化合物。为了探索这种远程Cat-CVD技术的可能性，在不锈钢腔壁上涂覆SiO_2或Teflon。当制备这种涂层时，观察到H原子密度增加一个数量级，表明有机硅化合物的远程Cat-CVD可以是制备薄固体膜的有前途的技术。少

Silicon nitride and silicon carbon nitride films have attractive properties, such as wear resistance, chemical inertness, transparency, and insulatability. Device quality silicon nitride films can be fabricated from SiH_4 and NH_3 by using a catalytic chemical vapor deposition (Cat-CVD) technique. It is possible to coat organic materials, such as organic light-emitting diodes and plastic films for packaging. The problem is that SiH_4 is highly explosive and alternative materials are expected. Hexamethyldisilazane (HMDS) is one of the attractive materials to replace SiH_4. In the present study, the Cat-CVD processes of HMDS and trisdimethylaminosilane were focused.Gas-phase diagnoses were performed by employing three kinds of mass spectrometric techniques: electron impact quadrupole mass spectrometry, vacuum-ultraviolet photoionization time-of-flight mass spectrometry, and ion attachment quadrupole mass spectrometry. Combining the results of these mass spectrometric measurements, it was … More revealed that Si-N bonds are broken selectively although they are stronger than Si-C bonds. The lone-paired electrons of N atoms may interact with the catalyzer to break the bonds selectively. A steric hindrance must be present to break Si-C bonds. It was also found that the decomposition efficiency of NH_3 decreases drastically by the addition of HMDS. This suggests that HMDS poisons the catalyzer surfaces and blocks the decomposition of NH_3. One of the techniques to overcome this poisoning problem is remote Cat-CVD in which NH_3 or H_2 is decomposed on catalyzer surfaces and the produced radicals are transported to down streams where organic silicon compounds are introduced. In order to explore the possibility of this remote Cat-CVD technique, the stainless-steel chamber walls were coated with SiO_2 or Teflon. An increase in H-atom density by one order of magnitude was observed when such coatings were made, showing that remote Cat-CVD of organic silicon compounds can be a promising technique to prepare thin solid films. Less