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This paper discusses tensile testing techniques and results derived as part of a broader microstructure-properties investigation of structural materials used in surface micromachined (SMM), and LIGA MEMS technologies. SMM techniques produce devices on the surface of a silicon wafer, with critical dimensions as small as 1–2 μm, using a subtractive multilayer film deposition process. Two structural materials have been investigated: SUMMiT™ polysilicon and amorphous Diamond (a-D). Mechanical properties presented in this paper on these SMM structural materials were obtained from a direct tensile testing method using the lateral force measurement capability of a nanoindentation system. LIGA, a German acronym extracted from the words “Lithographie, Galvanoformung, Abformung,” is an additive process in which structural material is electrodeposited into a polymethyl-methacrylate (PMMA) molds realized by deep x-ray lithography. LIGA tensile specimens of several different materials have been evaluated using a mini-servohydraulic load frame, designed to test specimens of sizes similar to structural components. In this paper, tensile test results from LIGA fabricated Ni and Ni-alloys and examples of their correlation to processing and microstructure will be presented. [ABSTRACT FROM AUTHOR]

Mechanical testing of thin fills for MEMS has progressed from a developmental stage to a point where validated techniques are used to study the behavior of devices and materials at a very fine scale. Tensile data coveting a range of sizes and test techniques have been analyzed to examine the distribution of defects that would be responsible for the observed fracture strengths. For each sample, a critical defect size was calculated based on a published fracture toughness and a half-circular surface crack fracture toughness model. For polysilicon produced using the SUMMiT V process in the period 1998-1999, the calculated mean defect size was 115 nm. For polysilicon produced using the MUMPS process, the calculated mean defect size was 389 nm. [ABSTRACT FROM AUTHOR]