物理化学学报 >> 2004, Vol. 20 >> Issue (12): 1399-1403.doi: 10.3866/PKU.WHXB20041201

研究论文    下一篇

三甲基氯硅烷对纳米多孔二氧化硅薄膜的修饰

王娟; 张长瑞; 冯坚   

  1. 国防科学技术大学航天与材料工程学院,新型陶瓷纤维及其复合材料国防科技重点实验室,长沙 410073
  • 收稿日期:2004-04-14 修回日期:2004-05-21 发布日期:2004-12-15
  • 通讯作者: 王娟 E-mail:zhucheng88@sohu.com

Modification of Nanoporous Silica Film by Trimethylchlorosilane

Wang Juan; Zhang Chang-Rui; Feng Jian   

  1. Key Laboratory of Advanced Ceramic Fibers and Composites, College of Aerospace and Material Engineering, National University of Defense Technology, Changsha 410073
  • Received:2004-04-14 Revised:2004-05-21 Published:2004-12-15
  • Contact: WANG Juan E-mail:zhucheng88@sohu.com

摘要: 以正硅酸乙酯为先驱体,采用溶胶-凝胶法,结合旋转涂胶、超临界干燥工艺在硅片上制备了纳米多孔SiO2薄膜.用三甲基氯硅烷(TMCS)对该SiO2薄膜进行了表面修饰,采用FTIR、TG-DTA、AFM和椭偏仪等方法研究了TMCS修饰前后薄膜的结构、形貌、厚度与介电常数等性能.超临界干燥后的SiO2薄膜含有Si-O-Si与Si-OR结构,呈疏水性.在空气中250 ℃以上热处理后SiO2薄膜因含有Si-OH而呈吸水性. TMCS修饰后的SiO2薄膜在温度不高于450 ℃时可保持其疏水性和多孔结构. SiO2薄膜经TMCS修饰后基本粒子和孔隙尺寸增大,孔隙率提高,介电常数可降低至2.5以下.

关键词: 纳米多孔SiO2薄膜,  溶胶-凝胶,  三甲基氯硅烷,  低介电常数(lowκ)

Abstract: Crack-free homogeneous nanoporous silica films on silicon wafers have been synthesized via supercritical drying of wet gel films that were obtained by spin coating the polymeric silica sol using sol-gel method with tetraethoxysilane(TEOS) as precursor. The silica film was composed of Si-O-Si and Si-OR characterized by FTIR and was hydrophobic. But the silica film became hydrophilic because of Si-OH group after it was heat treated above 250 ℃ in air. So the silica film was modified by trimethylchlorosilane(TMCS) in order to get hydrophobic, thermal stable film with low dielectric constant. The modified silica film was characterized by FTIR, AFM and spectroellipsometer. The modified silica film can keep hydrophobic and its nanoporous structure at temperature lower than 450 ℃ in nitrogen. The sizes of SiO2 primary particles and pores of silica film became larger after modification. The modified silica film had higher porosity and lower dielectric constant. Its dielectric constant could be reduced to below 2.5.

Key words: Nanoporous silica film,  Sol-gel,  TMCS,  Low dielectric constant(lowκ)