Size effect on brittle-ductile transition temperature of silicon by means of tensile testing

This paper reports the size effect on brittle-ductile transition temperature (BDTT) of single crystal silicon (SCS) using different width specimens (120-μm long, 5-μm thick and 4 or 9-μm wide). The BDTT was characterized using tensile testing in a vacuum from room temperature to 600 °C. The fractured specimens showed that the slips were occurred at 500 °C and above, which indicated that the BDTT of micrometer-sized silicon decreased compared to millimeter-sized structures. By comparing the temperature ranges of the slip occurrences among the different sized specimens including other researchers´ reports, we found that the length along slips-propagation direction, i.e. thickness, might dominate the BDTT.