CAJ | 학술논문

温度载荷能够引起 MEMS 多层薄膜结构发生翘曲和分层等失效模式，而界面应力则是引起这些失效的直接原因。根据Suhir.E的双金属带热应力分布理论，对温度载荷作用下MEMS界面中的剪应力和剥离应力的分析表明，这两种应力随着与界面中心距离的增大呈指数增加，在界面端处达到最大值。界面应力与材料热膨胀系数和所加载温度呈线性相关，另外还与两材料层的厚度密切相关。以铜/铬组成的双层结构为例，利用 Matlab 数值仿真研究了界面应力与材料层厚度的关系，结果表明，界面应力与两材料层厚度比有关，当铜层和铬层厚度比为1.5时，层间剪应力和剥离应力均较小，可有效提高MEMS结构的可靠性，降低分层失效的概率。
온도재하능구인기 MEMS 다층박막결구발생교곡화분층등실효모식，이계면응력칙시인기저사실효적직접원인。근거Suhir.E적쌍금속대열응력분포이론，대온도재하작용하MEMS계면중적전응력화박리응력적분석표명，저량충응력수착여계면중심거리적증대정지수증가，재계면단처체도최대치。계면응력여재료열팽창계수화소가재온도정선성상관，령외환여량재료층적후도밀절상관。이동/락조성적쌍층결구위례，이용 Matlab 수치방진연구료계면응력여재료층후도적관계，결과표명，계면응력여량재료층후도비유관，당동층화락층후도비위1.5시，층간전응력화박리응력균교소，가유효제고MEMS결구적가고성，강저분층실효적개솔。
The failure modes such as warp and delamination in MEMS multilayer structure will happen under thermal load, and the interfacial stress caused by thermal load is the immediate cause to the failure modes. By using bimetal strip stress model advanced by Suhir.E, interfacial shearing stress and peeling stress caused by thermal load were analyzed. The analysis shows that shearing stress and peeling stress present exponential increatse along with the distance from centre of bonded pair, and increase sharply in the end until achieve maximum. Interfacial stress is influenced linearly by difference of two material thermal expansivity and temperature loaded, and also influenced by the thickness of two material layers. Bi-layer structure composed by Cu/Cr was analyzed with Matlab on the relationship between interfacial stress and material thickness. The result shows that the interfacial stress is influenced by the thickness ratio of two material layers. When the thickness ratio of Cu to Cr layer is 1.5, the shearing stress and peeling stress is both small, which can reduce the probability of delamination failure mode.