化学气相沉积法制备碳化铬薄膜的研究

以三（2，2，6，6-四甲基-3，5-庚二酮）化铬为前驱体，采用化学气相沉积（CVD）法在氧化铝（Al₂O₃）陶瓷基板上制备碳化铬（Cr₃C₂）薄膜，其中沉积温度为723 K至923 K，沉积时间为1 200 s。研究了不同沉积温度对Cr₃C₂薄膜的相组成、择优取向、宏观表面、微观结构及电学性能的影响。结果表明，在723 K至923 K下制备得到具有高度（130）择优取向的Cr₃C₂薄膜。随着沉积温度的升高，Cr₃C₂薄膜表面先由光滑变粗糙，后逐渐变光滑；薄膜晶粒呈椭球型生长；薄膜的厚度先增加后减小，从而导致电阻先减小后增大。在798 K时制备得到厚度最大且电阻最小的（130）择优取向的最佳Cr₃C₂薄膜。同时，在实验条件下Cr₃C₂薄膜表面存在少量的碳和Cr₂O₃。

Preparation of Chromium Carbide Films by Chemical Vapor Deposition

Chromium carbide（Cr₃C₂） thin films were prepared on alumina（Al₂O₃） ceramic substrate by chemical vapor deposition（CVD） using tris（2，2，6，6-tetramethyl-3，5-heptanedione）chromium as a precursor，with the deposition temperatures in the range of 723 K to 923 K and deposition time of 1 200 s. Effects of different deposition temperatures on the phase composition，preferred orientation，macroscopic surface，microstructure and electrical properties of the Cr₃C₂ films were investigated，respectively. The results show that Cr₃C₂ films with a high （130） preferred orientation were prepared in the deposition temperature range of 723 K to 923 K. As the deposition temperature increases，the surface of the Cr₃C₂ films firstly changes from smooth to rough，and then gradually becomes smooth；the crystal grains of the films grow in an ellipsoid shape； the thickness of the films firstly increases and then decreases，leading to the resistance firstly decreases and then increases. The preferentially oriented （130） Cr₃C₂ film with maximum thickness and minimum resistance is prepared at 798 K. At the same time，there is a small amount of carbon and Cr₂O₃ on the surface of the Cr₃C₂ films under the experimental conditions.