Maslar James E, Kimes William A, Sperling Brent A
National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
J Res Natl Inst Stand Technol. 2019 Mar 26;124:1-15. doi: 10.6028/jres.124.005. eCollection 2019.
Thin film vapor deposition processes, e.g., chemical vapor deposition, are widely used in high-volume manufacturing of electronic and optoelectronic devices. Ensuring desired film properties and maximizing process yields require control of the chemical precursor flux to the deposition surface. However, achieving the desired control can be difficult due to numerous factors, including delivery system design, ampoule configuration, and precursor properties. This report describes an apparatus designed to investigate such factors. The apparatus simulates a single precursor delivery line, e.g., in a chemical vapor deposition tool, with flow control, pressure monitoring, and a precursor-containing ampoule. It also incorporates an optical flow cell downstream of the ampoule to permit optical measurements of precursor density in the gas stream. From such measurements, the precursor flow rate can be determined, and, for selected conditions, the precursor partial pressure in the headspace can be estimated. These capabilities permit this apparatus to be used for investigating a variety of factors that affect delivery processes. The methods of determining the pressure to (1) calculate the precursor flow rate and (2) estimate the headspace pressure are discussed, as are some of the errors associated with these methods. While this apparatus can be used under a variety of conditions and configurations relevant to deposition processes, the emphasis here is on low-volatility precursors that are delivered at total pressures less than about 13 kPa downstream of the ampoule. An important goal of this work is to provide data that could facilitate both deposition process optimization and ampoule design refinement.
薄膜气相沉积工艺，例如化学气相沉积，广泛应用于电子和光电器件的大规模制造中。确保所需的薄膜性能并最大限度地提高工艺产量需要控制到达沉积表面的化学前驱体通量。然而，由于众多因素，包括输送系统设计、安瓿配置和前驱体性质，实现所需的控制可能很困难。本报告描述了一种旨在研究此类因素的装置。该装置模拟化学气相沉积工具中的单个前驱体输送管线，具有流量控制、压力监测和一个装有前驱体的安瓿。它还在安瓿的下游并入了一个光学流通池，以允许对气流中的前驱体密度进行光学测量。通过这些测量，可以确定前驱体流速，并且在选定的条件下，可以估计顶空中的前驱体分压。这些功能使该装置可用于研究影响输送过程的各种因素。讨论了确定压力以（1）计算前驱体流速和（2）估计顶空压力的方法，以及与这些方法相关的一些误差。虽然该装置可以在与沉积过程相关的各种条件和配置下使用，但这里重点关注在安瓿下游总压力小于约13 kPa下输送的低挥发性前驱体。这项工作的一个重要目标是提供有助于沉积工艺优化和安瓿设计改进的数据。
