【作者】 肖青平；

【导师】 吴萍；

【作者基本信息】 天津大学 ， 材料物理与化学， 2007， 硕士

【摘要】 非晶碳氮薄膜由于具有良好的物理性质而备受关注,在防护涂层、电子学器件以及生物医学等领域有着广阔的应用前景。辐照是常用的材料改性手段之一。本文通过双对向靶直流磁控溅射法制备了非晶碳氮薄膜,并对制备后的样品进行电子束辐照,研究了电子束辐照对薄膜结构和力学性质的影响。结构分析表明,随着氮分压的增大,薄膜中氮含量CN先由8.9%增大至22%,然后逐渐减小,sp3键含量减少而sp2键区域的尺寸和数目都有所增加,薄膜趋于石墨化。经电子束辐照后,由于薄膜表面处发生氮化和氧化,各氮分压条件下制备的薄膜中氮含量均有不同程度的提高,最大值为25.4%。薄膜表面各元素的价键结构在辐照后有了较大改变。由于电子束对薄膜的电离和位移效应,薄膜内sp3C键被破坏,形成未饱和的sp2C悬键并形成sp2团簇,薄膜更加趋于石墨化。纳米刻痕测试表明,随着氮分压的增加,薄膜硬度从17.9 GPa缓慢下降14.4 GPa然后逐渐回升,与氮含量随氮分压的变化趋势相反。辐照后由于结构的变化使薄膜硬度有所下降。更多还原

【Abstract】 Amorphous carbon nitride films have attracted the attentions of various investigators due to their great physic properties and wide range of promising applications such as protecting coatings, electronic devices and biomedicine devices. Irradiation is one of the most commonly used techniques for tailoring materials’properties. In this paper, carbon nitride films were fabricated by a dc facing-target magnetron reactive sputtering system, and then the prepared samples were irradiated by electron beam. The effects of electron beam irradiation on the structure and mechanical properties of carbon nitride films have been carefully studied.As the structure characterization shows, with the increase of nitrogen partial pressure (PN), the nitrogen content (CN) in the films increases from 8.9% to 22% firstly, and then decreases gradually, the content of sp3 bonding decreases and the number and size of sp2 clusters increase, graphitization occurs in the CN films. After electron beam irradiation the CN in films prepared at different PN conditions increase variously because of the oxide and nitride effects occurring at the surface. The maximized CN reaches 25.4%. The bonding structures at the films’surface have changed a lot after irradiation. The bond breaking event and displacement event take place when electron beam is introduced into the films .The sp3C bonds are break, and change to the unsaturated sp2C hanging bonds. When these sp2 bonds connect with each other, sp2 clusters form. Graphitization behaves more deeply in the films.The results of nanoindention tests indicate that the hardness of films decrease from 17.9 GPa to 14.4 GPa firstly, and then increase gradually, which is contrary to the trend of CN vs. PN. The hardness decreases after electron irradiation, which is consistent with the change of structure.更多还原