Abstract
A micro-tensile testing system has been developed to measure the mechanical properties of post-buckled silicon dioxide micro-bridge beams. A kind of vernier-groove carrier is presented to improve alignment precision and repeatability of the measurement, and the stiffness coefficient of the tensile system is calibrated in situ in order to obtain the deformation of the tensile beams. Through analyzing a series of stress states in the beam over film preparation, post-buckling and unfolding of the beam, the initial residual stress in the film is obtained from the original load–displacement curves. The residual stress of 354 MPa is consistent with that calculated from the theory of finite deflection of buckled beams. Young’s modulus and tensile fracture strength are also obtained from the load–displacement curves. The measured modulus and strength are 64.6 ± 3 GPa and 332–489 MPa respectively. The measured properties of the thermal silicon dioxide film are reasonably coherent with other reports.
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References
Bagdahn J, Sharpe WN, Jadaan O (2003) Fracture strength of polysilicon at stress concentrations. J Microelectromech Syst 12:302–312
Bamberg E, Grippo CP, Wanakamol P, Slocum AH, Boyce MC, Thomas EL (2006) A tensile test device for in situ atomic force microscope mechanical testing. Precis Eng 30:71–84
Brotzen FR (1994) Mechanical testing of thin films. Int Mater Rev 39:24–45
Carr SM, Lawrence WE, Wybourne MN (2005) Static buckling and actuation of free-standing mesoscale beams. IEEE T Nanotechnol 4:655–659
Denhoff MW (2003) A measurement of Young’s modulus and residual stress in MEMS bridges using a surface profiler. J Micromech Microeng 13:686–692
Fang W, Wickert JA (1994) Post buckling of micromachined beams. J Micromech Microeng 4:116–122
Gaspar J, Schmidt M, Held J, Paul O (2008) High-throughput wafer-scale microtensile testing of thin films. In: 21st IEEE international conference on micro electro mechanical systems (MEMS 2008)
Guckel H, Randazzo T, Burns DW (1985) A simple technique for the determination of mechanical strain in thin films with application to polysilicon. J Appl Phys 57:1671–1675
Haque A, Saif MTA (2002) Application of MEMS force sensors for in situ mechanical characterization of nano-scale thin films in SEM and TEM. Sens Actuators A Phys 97:239–245
Isono Y, Namazu T, Terayama N (2006) Development of AFM tensile test technique for evaluating mechanical properties of sub-micron thick DLC films. J Microelectromech Syst 15:169–180
Kamiya S, Kuypers J, Trautmann A, Ruther P, Paul O (2007) Process temperature-dependent mechanical properties of polysilicon measured using a novel tensile test structure. J Microelectromech Syst 16:202–212
Luo C, Francis A, Liu XC (2008) Determination of compressive residual stress in a doubly-clamped microbeam according to its buckled shape. Microelectron Eng 85:339–347
Sato K, Yoshioka T, Ando T, Shikida M, Kawabata T (1998) Tensile testing of silicon film having different crystallographic orientations carried out on a silicon chip. Sens Actuators A Phys 70:148–152
Sharpe WN, Jackson KM, Hemker KJ, Xie Z (2001) Effect of specimen size on Young’s modulus and fracture strength of polysilicon. J Microelectromech Syst 10:317–326
Sharpe WN, Pulskamp J, Gianola DS, Eberl C, Polcawich RG, Thompson RJ (2007) Strain measurements of silicon dioxide microspecimens by digital imaging processing. Exp Mech 47:649–658
Stoney GG (1909) The tension of metallic films deposited by electrolysis. Proc R Soc 82:172–175
Takahiro N, Yoshitada I, Takeshi T (2000) Evaluation of size effect on mechanical properties of single crystal silicon by nanoscale bending test using AFM. J Microelectromech Syst 9:450–459
Tsuchiya T, Inoue A, Sakata J (2000) Tensile Testing of Insulating Thin Films; Humidity Effect on Tensile Strength of SiO2 Films. Sens Actuator A Phys 82:286–290
Weihs TP, Hong S, Bravman JC, Nix WD (1988) Mechanical deflection of cantilever microbeams: a new technique for testing the mechanical properties of thin films. J Mater Res 3:931–942
Yang J, Gaspar J, Paul O (2008) Fracture properties of LPCVD silicon nitride and thermally grown silicon oxide thin films from the load-deflection of long Si3N4 and SiO2/Si3N4 diaphragms. J Microelectromech Syst 17:1120–1134
Zhang TY, Su YJ, Qian CF, Zhao MH, Chen LQ (2000) Microbridge testing of silicon nitride thin films deposited on silicon wafers. Acta Mater 48:2843–2857
Zhou ZM, Zhou Y, Yang CS, Chen JA, Ding W, Ding GF (2006) The evaluation of Young’s modulus and residual stress of copper films by microbridge testing. Sens Actuators A Phys 127:392–397
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This work was funded by the National Natural Science foundation of China “Measurement Technique and Theory Research of Microelectromechanical System” (Grant No.50535030).
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Zhang, D., Chu, J. Mechanical characterization of post-buckled micro-bridge beams by micro-tensile testing. Microsyst Technol 16, 375–380 (2010). https://doi.org/10.1007/s00542-009-0934-y
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DOI: https://doi.org/10.1007/s00542-009-0934-y