Evaluation of Elastic Property of Thin Films by MEMS Results Key Idea For elastically isotropic thin film Strain Biaxial Elastic Modulus Free-hang Bridge

Fundamental Adhesion Energy Measurement Buckling under Residual Compressive Stress & Energy Balance Results T : Elastic energy U : Bending strain energy Δγ : Surface energy =(- gfs+ gfv+ gsv)

In-situ Stress Measurement System He-Ne laser : 632.8nm Step-motor : 1 rpm Lens FL : 500mm PSD : S1300 (13×13mm) Mirror Mirror Step- Motor Beam Splitter Chamber He-Ne laser In-situ stress measurement with temperature variation i.e. Stress relaxation mechanism. In-situ stress measurement under various environments i.e. Stress vs. Humidity Mirror PSD Interface 5

Residual Stress Measurement Principle Measurement of curvature Results Curvature (R) ds df Assumptions 1.The bending displacement is small compared with the thickness of the substrate 2. For a very thin deposit. ( ds << df ) Residual stress versus. DC bias voltage In Filtered Cathodic Arc Deposition

Current-Voltage Measurement I-V Curve & Fluctuation Measuring System Emission Pattern Observing System CCD Viewing System Spacer Phosphor coated ITO-glass y Viewing System e Cathode e z CCD Visible Light Anode x 3-D Manipulator Cathode Keithley 6517 Electrometer SRS PS350 Power Supply SRS PS350 Power Supply Computer Interface Keithley 6517 Electrometer Emission Behavior from Vitreous Carbon Emission Pattern from Vitreous Carbon I-V Curve F-N Plot

Friction Behaviors of Pure DLC and Si-DLC in Ambient Environment Ball On Disc Type Tribometer Principle Results 따라서 본 연구에서는 낮은 마찰계수와 Si-rich oxide debris 사이의 관계를 좀 더 자세히 연구하기 위해 Si 함유 DLC 필름의 환경변화에 따른 마찰 특성과 Tribochemical reacion 과의 관계를 조사하고, 특히 대기중에서의 마찰거동에 많은 영향을 주는 습기와 산소가 없는 Dry Air와 vacuum 분위기에서 마찰특성을 실험으로써 Si 함유 DLC 필름의 대기중에서의 낮고 안정된 마찰 거동의 원인과 메카니즘을 규명하고자 하였습니다. Fn Ball Film Ft Substrate Ft : Tangential Force Fn : Normal Force Friction Behaviors of Pure DLC and Si-DLC in Ambient Environment Friction Coefficient

Surface Energy Measurement Results Principle l Sessile-drop  s sl Substrate High Surface Energy Low Surface Energy s : Substrate tension l : Liquid tension sl : Interface tension  : Contact angle  p : Polar component d : Dispersive component Effects of CF4 Plasma Treatment of DLC Films

Adhesion Measurement Scratch tester Results Principle (a) (b) Visual examination of the scratch to determine the critical load Fc that causes adhesion failure Analysis of emission of acoustic signals that are small in magnitude when the film adheres at low load (b) Fractures morphology of DLC films (a) DLC on Tool Steel (b) DLC on Tool Steel with W interlayer