Characterization of mechanical properties of MEMS materials

MEMS 材料机械性能表征

基本信息

批准号：
10305008
负责人：
SATO Kazuo
金额：
$ 23.1万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A).
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10305008/
关键词：
micromachine thin films mechanical properties tensile testing MEMS single-crystal silicon size effect fatigue 試験法シリコン化合物

项目摘要

(1) We developed a new type of tensile testing method to characterize thin films utilized as structural materials for MEMS.In the proposed "on-chip tensile testing method", test is carried out on a silicon chip containing a loading mechanism and a tensile specimen on a same chip. The developed system allows both quasi-static and dynamic fatigue testing.(2) We designed and fabricated test chips for different film materials such as (a) single crystal silicon in three different orientations, (b) SiO2, (c) Si3N4, (d) poly-crystalline silicon. We obtained fracture stress and strain, and Young's modulus of above-mentioned materials.(3) Single crystal silicon showed 5% elastic strain until fracture. This is much higher than values obtained from bulk silicon by bending test. We also observed a size-effect of the specimen on fracture strain. Smaller specimen showed larger fracture strain though both are tested by on-chip method.(4) Cyclic loading influenced on the fracture of single crystal silicon. Number of cycles when silicon fractured decreased according to the increase in applied peak value of strain. The fracture mechanism is under discussion.(5) Crack growth of the silicon specimen was observed in-situ by using a carbon-nano-tube attached on an AFM probe tip. From a change in crack profile, it was suggested plastic deformation might be introduced to the specimen. This is against the common knowledge that silicon does not show any plasticity at room temperature. Further investigation is needed.(6) We succeeded in tensile test for Si3N4 film 0.1 micron thick. We further designed a test system allowing a tensile test for films 0.01 micron thick. We expect a surface effect appear on the film property by decreasing the thickness.

（1）我们开发了一种新型的拉伸测试方法来表征被用作MEM的结构材料的薄膜。在拟议的“芯片上拉伸测试方法”中，对包含加载机制和拉伸的硅芯片进行了测试同一芯片上的标本。开发的系统允许准静态和动态疲劳测试。（2）我们为不同的膜材料设计和制造了测试芯片，例如（a）三种不同方向的（a）单晶硅，（b）Sio2，（c）Si3n4，（（ d）聚晶硅。我们获得了断裂应力和应变，以及杨氏上述材料的模量。（3）单晶硅显示5％弹性应变直至裂缝。这远远高于通过弯曲测试从散装硅获得的值。我们还观察到标本对断裂应变的尺寸效应。较小的标本显示出较大的断裂应变，尽管两者都通过片上测试。（4）对单晶硅断裂影响的环状负荷。硅骨折时的循环数量根据菌株的应用峰值增加而减少。（5）通过使用附着在AFM探针尖端上的碳纳米管观察到硅样品的裂纹生长。从裂纹轮廓的变化中，建议将塑性变形引入样品。这违反了以下常见，即硅在室温下没有显示任何可塑性。需要进一步研究。（6）我们在Si3n4膜0.1微米厚的拉伸试验中取得了成功。我们进一步设计了一个测试系统，允许对0.01微米厚的膜进行拉伸测试。我们期望通过减小厚度在膜特性上出现表面效应。