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目的：通过疏水性质的研究，证明源电极式和浸入式 PECVD 方法制备含氢 DLC 膜存在结构和性质上的差别，并且证明浸入式PECVD方法制备的含氢DLC膜更适于需要强疏水性的表面改性应用。方法在PECVD腔体中通入甲烷和氢气混合气体，同时在面对源电极的绝缘样品架上放置石英基片并沉积类聚合物DLC膜；在源电极上放置石英基片并沉积常规含氢DLC膜。在PECVD腔体中通入乙炔、氢气和四氟化碳混合气体，在面对源电极的绝缘样品架上放置石英基片并沉积掺氟 DLC 膜。改变气体压强和射频功率，生长一系列含氢DLC膜。利用紫外可见近红外光度计测试DLC膜的透射谱，扫描电子显微镜及原子力显微镜测试其表面形貌。利用接触角测量仪测试两种含氢DLC和一种掺氟DLC膜表面与水、甘油、乙二醇的接触角，并计算其表面能。比较两种含氢DLC膜接触角和表面能的差别，并根据类聚合物DLC膜的微观结构分析可能的原因。比较掺氟和不掺氟DLC膜的接触角并讨论比较结果。结果类聚合物DLC膜的接触角和表面能与具有相同光学带隙的常规含氢DLC膜存在明显差异。类聚合物DLC膜的接触角更大，表面能更低，因而具有更强的疏水性。类聚合物和常规含氢DLC膜与蒸馏水的接触角最大分别为91.2°和79.2°。类聚合物DLC膜中的碳原子具有更高的氢化率，可能是它表面能低和疏水性好的原因。掺氟DLC膜的接触角比具有相同带隙的类聚合物和常规含氢DLC膜都低，这与文献报道的掺氟能提高接触角的现象完全相反。结论类聚合物DLC膜的疏水性更强。结合其更小的内应力、更宽的光学带隙范围和更快的生长速度等特征，使它在医疗、光学保护涂层等领域具有更强的应用性。浸入式 PECVD 方法生长的掺氟 DLC 膜不但未提高反而降低了 DLC膜的疏水性，需要更多的研究来揭示其中的原因。

ABSTRACT:Objective By studying the hydrophobic property, the work aimed to prove the structure and property differ-ences between different hydrogenated DLC films prepared by the source electrode and the immersion PECVD method, and demonstrate that hydrogenated DLC film prepared by immersion PECVD method is more suitable for the applications requiring highly hydrophobic surface modification. MethodsPECVD chamber was filled with methane and hydrogen gas mixture, some quartz substrates were mounted on the powered electrode to grow conventional hydrogenated DLC films; other quartz substrates were mounted on an insulating sample holder that was facing the powered electrode to grow polymeric DLC films. PECVD chamber was filled with acetylene, hydrogen, andtetrafluoromethane gas mixture, quartz substrates were mounted on an insu-lating sample holder that was facing the powered electrode to grow fluorine-doped hydrogenated DLC films. UV-visible absorp-tion spectra of DLC films were measured using a UV-visible spectrophotometer, SEM and AFM devices were used to analyze the surface morphology of the obtained DLC films. Contact angles with water, glycerin, and glycol were measured and used to calculate the surface free energy of the polymeric and conventional hydrogenated DLC films. The contact angles and the surface free energies of the two types of hydrogenated DLC films were compared, and the possible cause was discussed according to the microstructure of the polymeric DLC films. The contact angles of fluorine-doped and nondoped hydrogenated DLC films were compared and the result was discussed.ResultsThe polymeric DLC films had quite different contact angles and surface free energies comparing to conventional hydrogenated DLC films with an identical optical gap. The polymeric DLC film had bigger contact angle, smaller surface free energy, and therefore better hydrophobic properties. The maximum contact angles with water for the polymeric and conventional hydrogenated DLC films were 91.2° and 79.2° respectively. Polymeric DLC film had a higher hydrogenation rate for its sp3 carbon atoms, and this could be the cause for its low surface free energy and good hydro-phobic properties. The fluorine-doped DLC film had a lower contact angle than both the polymeric and conventional hydroge-nated DLC films with an identical optical gap, this contradicted the reported phenomena of increased contact angles for fluo-rine-doped DLC films.ConclusionPolymeric DLC film has better hydrophobic properties. Considering its other characteristics such as lower internal stress, wider range of optical gaps, and higher deposition speed, polymeric DLC film is more applicable in the field of medical and optical protection films. The fluorine-doped DLC film grown with the immersive PECVD method has lower instead of higher hydrophobic properties, and further investigations are needed to elucidate its cause.