Composition Determining Mechanism in Synthesis of Silicon Carbide Films from SiH2CI2/C2H2 Chemical Vapor Deposition System

二氯矽甲烷/乙炔化學氣相沉積系統合成碳化矽薄膜的組成決定機構

洪儒生(Lu-Sheng Hong) ； 吳常明(Chang-Ming Wu)

《Journal of the Chinese Institute of Chemical Engineers》 31卷1期 (2000/01) Pp. 79-89

https://doi.org/10.6967/JCICE.200001.0079

摘要

本文乃探討二氯矽甲烷/乙炔為化學氣相沉積先驅物在合成碳化矽薄膜時的薄膜成長機構。碳化薄膜成長實驗是在一水平熱壁式反應器進行。反應溫度在攝氏八百度以及總壓為九毫米汞柱下，二氯矽甲烷的進料濃度必須過量才能獲得碳化矽薄膜。由增加反應器的體積對表面積比值發現，成長薄膜中的碳矽組成比會隨之變大。此一變化與原料先驅物的反應途徑有關。經由一稱為”macro/microcavity”的實驗手法分析結果發現，薄膜成長途徑為：〈１〉二氯矽甲烷直接與吸附的乙炔在基材表面反應並以4.0*10-7的附著機率形成碳化矽薄膜；二氯矽甲烷先氣相分解為二氯化矽的中間產物，之後再與乙炔反應並以0.1的附著機率形成過剩的碳沈積。

並列摘要

The reaction paths that determine the film composition of silicon carbide (SiC) in a chemical vapor deposition system using SiH2Cl2/C2H2 as the reactant gases are investigated. Deposition reaction has been performed in a horizontal hot-wall tubular reactor where SiC films are produced at 1073 K and 9 torr total pressure in the presence of excess SiH2Cl2. By varying the reactor volume-to-surface ratio (VIS), the composition ratio of carbon to silicon of the films in- creases with VIS. The change of the film composition is attributed to the variation of the film growth paths of the reactant gases. An experimental method named the macro/microcavity is applied to evaluate the film growth paths and their contribution to the film growth. A growth mechanism is proposed as follows: (1) SiH2Cl2, directly diffuses to the substrate and reacts with the adsorbed C2H2 with a sticking probability of 4.0 10-7 to form stoichiometric SiC, (2) SiCl2, an initial product of the gas-phase decomposition of SiH2Cl2, reacts with C2H2 with a sticking probability of 0.1 and causes excess carbon deposition.

並列關鍵字

Silicon Carbide Films ； Chemical Vapor Deposition ； Dichlorosilane ； Acetylene ； Films Growth Path