- Volume 37 Issue 4
DOI QR Code
Experimental and Finite Element Study of Tribological Characteristics of SU-8 Thin Film
실험 및 유한요소해석에 의한 SU-8 박막의 Tribological 특성 연구
- Yang, Woo Yul (Dept. of Mechanical Engineering, Hannam Univ.) ;
- Shin, Myounggeun (Dept. of Mechanical Engineering, Hannam Univ.) ;
- Kim, Hyung Man (Dept. of Mechanical Engineering, Hannam Univ.) ;
- Han, Sangchul (Dept. of Mechanical Engineering, Hannam Univ.) ;
- Sung, In-Ha (Dept. of Mechanical Engineering, Hannam Univ.)
- Received : 2012.07.17
- Accepted : 2012.12.02
- Published : 2013.04.01
In this study, two-dimensional finite element models were developed and experiments were conducted using an atomic force microscope to investigate the tribological characteristics of an SU-8 layer coated on a patterned wafer for microsystem applications. The results revealed that both the adhesion and the friction forces measured by the atomic force microscope were lower for the SU-8 coated surface than for the bare silicon surface. This is attributed to the hydrophobicity of SU-8. Another important result derived from the finite element analysis was the critical load required to fracture the SU-8 film with respect to the thickness. The critical loads for thicknesses of 200, 400, and 800 nm were approximately 13, 22, and 28 mN, respectively, which corresponded to a Hertzian contact pressure of 1.2-1.8 GPa. These results will aid in the design of a suitable SU-8 thickness for microsystem components that are in contact with one another.
Supported by : 한국연구재단
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