摘要
本文介绍压电石英晶体谐振器探测沉积膜厚度及速率的工作原理。根据石英晶体和沉积膜层的切变弹性声阻抗理论,并利用在界面处的输入阻抗概念,导出了沉积一种材料膜层时复合系统的谐振频率变化与沉积层材料声阻抗和质量之间的理论关系式,进而导出了沉积多种材料膜层系时的理论关系式。这些关系式是使用石英谐振器精确探测沉积膜层的科学依据。
the operation principle of the piezoelectric quartz crystal resonators which can detect deposited film layers thickness and deposition rate is presented, based on the theory of shear-mode elastic acoustic impedance of quartz and deposited film layer, and with the use of the concept of input impedance of the film layer, an equation relating the resonant frequency shift of the quartz-film composite system to the mass and acoustic impedance of a single deposited material can be derived. Furthermore, the equations, which are of great worth to applications, of the deposited a sequence of various material film layers can be also derived. These equations will provide scientific foundation for accurate detection.
关键词
石英晶体
谐振器
沉积膜
探测
resonant frequency, acoustic impedance, shear wave velosity
