| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advanced Characterization Techniques for Quantifying and Modeling Deformation
|
| Presentation Title |
Micromechanical Characterization of Single-crystalline Silicon at Elevated Temperature |
| Author(s) |
Kosuke Takagi, Yoji Mine, Jun Fujise, Bonggyun Ko, Toshiaki Ono, Kazuki Takashima |
| On-Site Speaker (Planned) |
Kosuke Takagi |
| Abstract Scope |
Micro-bending tests were performed at a temperature ranging from 300 to 823 K using Si single crystals with different characteristic lengths to investigate the effects of size and temperature on plasticity. Specimens with dimensions of 5‒20×10×50 μm^3 were obtained from an Si (11N purity). At 300‒723 K, a sudden fracture occurred within an initial elastic regime, while the fracture stress decreased with increasing temperature. Cleavages were observed along (111) and (11-1) planes at 300‒723 K. Above 773 K, the specimens were plastically deformed prior to cracking. The yield stress at 823 K increased with decreasing characteristic length, demonstrating a size effect with a power exponent of ~0.3. Transmission electron microscopy of the microstructure deformed at 823 K revealed gliding of dislocations with a Burgers vector of [011] and [-10-1], and the formation of (111) and (11-1) mechanical twins, which suggests that brittle-to-ductile transition occurs between 773 and 823 K. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |