薄膜應力與光彈應力智慧檢測技術

Characterization Technology for Thin Film Stress and Material Internal Stress

陳柏宇

《機械工業雜誌》 475期 (2022/10) Pp. 54-62

摘要

現今許多光學元件或高精密儀器皆需做鍍膜處理，然而薄膜應力過大時，可能會使得元件產生劇烈變形而導致結構損壞，因而薄膜應力估算非常重要。對於薄膜應力之量測，通常為利用Stoney方程式做計算，使用該方程式時，僅需量測基材於鍍膜前後之表面曲率，最後再將曲率代入該方程式中即可計算求得薄膜應力，因此選用適當的光學量測技術非常重要，故本文將針對常用之光學量測技術進行介紹。另外本文同時介紹光彈應力技術，而此技術為可直接獲得材料內部之應力，因此此方法皆可做為檢測薄膜應力之技術，同時也會分享實際應力量測之案例。

關鍵字

薄膜應力 ； 光學量測技術 ； 光彈法

並列摘要

Nowadays, the optical components or high-precision instruments need to have coating finishing; however, large thin film stress will cause severe deformation of the structure and damage the components. Therefore, accurate estimation of thin film stress is essential. In general, the thin film stress is determined by Stoney equation, which only requires application of curvature radius of a substrate before and after thin film coating into the equation to estimate the stress; and using an appropriate optical measurement technology is important. This article will focus on introduction of optical measurement technologies. In addition, application of photoelasticity for stress analysis will also be introduced in this article. The internal stress of a material can be estimated directly by adopting photoelasticity method. We will also present several practical cases of stress measurement in this article.

並列關鍵字

Thin film stress ； Optical measurement technology ； Photoelasticity

參考文獻

G.G. Stoney, “The tension of metallic films deposited by electrolysis,” Proc. R. Soc. Lond. A 82(553), 172-175, 1909.

M. Ohring, “Materials science of thin films: depositon & structure,” Academic Press, 2002.

K.K. Szwedowicz, “3D-deflectometry: Fast nanotopography measurement for the semiconductor industry,” Ph.D. dissertation, Dept. Applied Physics, Technische Universiteit Eindhoven, 32-40, 2006.

H.V. Tippur, S. Krishnaswamy, and A.J. Rosakis, “A coherent gradient sensor for crack tip deformation measurements: analysis and experimental results,” Int. J. Fract. 48, 193-204, 1991.

J. W. Dally and W. F. Riley, “Experimental stress analysis,” 3rd ed., New York: McGraw-Hill, 1991.