Mechanics and Tribology of MEMS Materials - prod.sandia.gov ...

Contents
ACKNOWLEDGEMENTS..............................................................................................4
PREFACE ....................................................................................................................13
1 DEVELOPMENT OF IMPROVED MECHANICAL TEST CAPABILITIES FOR SMM
MATERIALS ................................................................................................................14
1.1 Background on MEMS Strength Evaluation ..............................................................14
1.2 Improvement of MEMS Tensile Strength Evaluation Methodology ........................15
1.3 Development of a MEMS Mechanical Probe Station.................................................18
1.4 Development of next-generation SMM mechanical test structures and on-chip
force/displacement sensors........................................................................................................19
1.4.1 Pull-tab tensile specimens........................................................................................20
1.4.2 Fracture-toughness structures. .................................................................................21
1.4.3 Bend strength structures...........................................................................................22
1.4.4 Optical force transducer...........................................................................................22
1.5 References.......................................................................................................................23
2 STRENGTH DISTRIBUTIONS IN SUMMIT TM SMM POLYSILICON....................25
2.1 Weibull Analysis of Strength Distributions in SUMMiT TM Polysilicon ...................25
2.2 Critical Flaw Size Evaluation .......................................................................................27
2.3 Size-Dependence in Polysilicon Strength.....................................................................28
2.4 Layer Dependence on Strength.....................................................................................30
2.5 References.......................................................................................................................32
3 THE ROLE OF MICROSTRUCTURE IN SUMMIT TM POLYSILICON FAILURE ..33
3.1 Characterization of Polysilicon Microstructure .........................................................33
3.2 Simulating the Response of Polycrystalline Silicon ....................................................34
3.2.1 Simulation Procedure...............................................................................................34
3.2.2 Results and Discussion ............................................................................................35
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