Low Temperature Photo-CVD by Two-Step Excitation

在LSI过程中，低温度CVD技术的金属、绝缘子和半导体薄膜不需要电荷颗粒损坏。在低温度、气体相位刺激和表面反应的订单下，沉积高质量和高密度的薄膜必须是分开的和独立的控制。我们提出了“混合激励CVD （HE-CVD）”，用于表面反应的气体相位激发和UV光irradiation。我们已经编写了有关HE-CVD铝沉积三年（1983-1985年）的详细研究，并获得了以下结果。（1）我们测量了三甲基铝的紫外吸收光谱（TMA）。我们决定用一盏Xe灯做HE-CVD。（2）我们已经研究了TMA的蒸汽分解机制。在没有碳吸收的情况下订购obtaine A1薄膜，它必须使用任何含有甲基基本反应的羟基到生成甲基。一种激动人心的方法是，它可以生产以太坊将降解碳增加。Ethane可以在Photolysis中产生。（3）我们有一个HE-CVD装置。在250 ° C的情况下，使用TMA和氢，高纯度铝薄膜，而没有碳吸收沉积在硅薄膜上。它是由低温度下的混合激发CVD沉积的高质量铝薄膜组成的。混合激发CVD方法具有在VLSI技术中沉积互连金属的潜力，并在绝缘膜中沉积。

In LSI process, low temperature CVD technologies of metal, insulator, and semiconductor films without charged particle damage are required. In order to deposite high quality and high density thin films at low temperatures, a gas phase excitation and a surface reaction must be separated and independently controlled. We proposed a "Hybrid-Excitation CVD (HE-CVD)" in which plasma is used for a gas phase excitation and UV light irradiation for a surface reaction. We have carried out detailed studies on HE-CVD for aluminum deposition for three years (1983-1985) and obtained the following results.(1) We measured the UV absorption spectrum of trimethyl-aluminum(TMA). We decided to use a Xe lamp for HE-CVD.(2) We have investigated a vapor decomposition mechanism of TMA. In order to obtaine A1 films without carbon incorporation, it must be necessary to use hydrogen which reacts with methyl radical to generate methane. The excitation method which can produce ethane would decrease carbon incorporation. Ethane could be generated in photolysis.(3) We have constructed HE-CVD apparatus. Using TMA and hydrogen, high purity Al films without carbon incorporation were deposited on silicon wafers at 250゜C. It was concluded that high quality Al films were deposited by the Hybrid-Excitation CVD at low temperatures. The Hybrid-Excitation CVD method has a potential for deposition of interconnection metals in VLSI technology and for deposition of insulator films.