Design and in-situ mechanical testing system for probe card/UV-LIGA-Ni microspring

Author

Saotome, Yasunori ; Yokote, Satoshi ; Okamoto, Takeshi ; Kinuta, Seichin

Author_Institution

Dept. of Mech. Eng., Gunma Univ., Japan

fYear

2003

fDate

19-23 Jan. 2003

Firstpage

670

Lastpage

673

Abstract

In this study, we designed an S-type micro-spring for a probe card and fabricated it by UV-LIGA/Ni electroforming. The mechanical properties of electroformed Ni exhibits a lower Young´s modulus and a much higher tensile strength than those of conventional bulk material. Using a scanning electron microscope, a newly developed testing machine enables in-situ observation of a microspring during and after loading cycles. During repeated cycles, voids developed on the surface of the microspring, resulting in a decreased spring constant. This determines fatigue strength, and the S-N curves indicate superior characteristics.

Keywords

LIGA; Young´s modulus; fatigue testing; micromechanical devices; nickel; scanning electron microscopy; tensile strength; voids (solid); Ni; S-N curves; S-type micro-spring; decreased spring constant; fatigue strength; higher tensile strength; loading cycles; lower Young´s modulus; mechanical properties; mechanical testing system; probe card/UV-LIGA-Ni microspring; repeated cycles; scanning electron microscope; voids; Coils; Fabrication; Fatigue; Mechanical factors; Micromechanical devices; Microstructure; Probes; Scanning electron microscopy; Springs; System testing;

fLanguage

English

Publisher

ieee

Conference_Titel

Micro Electro Mechanical Systems, 2003. MEMS-03 Kyoto. IEEE The Sixteenth Annual International Conference on

ISSN

1084-6999

Print_ISBN

0-7803-7744-3

Type

conf

DOI

10.1109/MEMSYS.2003.1189838

Filename

1189838