SLOW CRACK-GROWTH IN SINGLE-CRYSTAL SILICON
SLOW CRACK-GROWTH IN SINGLE-CRYSTAL SILICON
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DOI：
10.1126/science.256.5063.1537
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发表时间：
1992-06-12
期刊：
影响因子：
56.9
通讯作者：
BROWN, SB
中科院分区：
文献类型：
--
作者：
CONNALLY, JA;BROWN, SB
在一个75微米长的单晶硅悬臂梁上测量了随时间变化的裂纹增长。预裂纹的扩展改变了梁的共振频率，而共振频率与裂纹长度相关。测量到的稳态裂纹扩展速率慢至2.9 x 10（-13）米/秒，尽管该设备可以测量到低至10（-15）米/秒的裂纹扩展速率。假设表面天然二氧化硅层的静疲劳是齿条生长的机制。这些实验证明了硅器件速率相关失效的可能性，以及线弹性断裂力学在小型微机械器件中的适用性。结果表明，在评价硅薄膜结构的可靠性时，必须考虑裂纹的缓慢扩展。
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 rack 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.