Science. 1992 Jun 12;256(5063):1537-9. doi: 10.1126/science.256.5063.1537.
Time-dependent crack growth has been measured on a precracked, single-crystal silicon cantilever beam 75 micrometers long that was excited at resonance. Growth of the precrack changes the resonant frequency of the beam, which is correlated to crack length. The measured steady-state crack growth rate was as slow as 2.9 x 10(-13) meter per second, although the apparatus can measure crack growth rates as low as 10(-15) meter per second. It is postulated that static fatigue of the native surface silica layer is the mechanism for crack growth. These experiments demonstrate the possibility of rate-dependent failure of silicon devices and the applicability of linear elastic fracture mechanics to small-scale micromechanical devices. The results indicate that slow crack growth must therefore be considered when evaluating the reliability of thin-film silicon structures.
对经过预裂纹处理的、长 75 微米的单晶硅悬臂梁进行了时变裂纹扩展测量，该梁在共振时受到激励。预裂纹的扩展改变了梁的共振频率，这与裂纹长度相关。测量到的稳态裂纹扩展速率最慢可达 2.9×10^(-13) 米/秒，尽管该设备可以测量低至 10^(-15) 米/秒的裂纹扩展速率。据推测，天然表面二氧化硅层的静态疲劳是裂纹扩展的机制。这些实验证明了硅器件的速率相关失效的可能性，以及线性弹性断裂力学在小型微机械器件中的适用性。结果表明，在评估薄膜硅结构的可靠性时，必须考虑缓慢的裂纹扩展。
