ISSN:
1013-9826
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Reliability is one of the most critical issues for designing practical MEMS devices. Inparticular, the fracture toughness of micro-sized MEMS elements is important, as micro/nano-sized flaws can act as a crack initiation sites to cause failure of such devices. Existing MEMS devices commonly use single crystal silicon. Fracture toughness testing upon micro-sized single crystal silicon was therefore carried out to examine whether a fracture toughness measurement technique, based upon the ASTM standard, is applicable to 1/1000th sized silicon specimens. Notched cantilever beam type specimens were prepared by focused ion beam machining. Two specimens types with different notch orientations were prepared. The notch plane/direction were (100)/[010], and (110)/[ _ ,110], respectively. Fracture toughness tests were carried out using a mechanical testing machine for micro-sized specimens. Fracture has been seen to occur in a brittle manner in bothorientations. The provisional fracture toughness values (KQ) are 1.05MPam1/2 and 0.96MPam1/2, respectively. These values meet the micro-yielding criteria for plane strain fracture toughness values (KIC). Fracture toughness values for the orientations tested are of the same order as values in the literature. The results obtained in this investigation indicate that the fracture toughness measurementmethod used is applicable for micro-sized components of single crystal silicon in MEMS devices
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/50/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.297-300.292.pdf
Permalink