微创手术式硅微机械加工（MISSM）技术

介绍了一种新颖的微创手术式硅微机械加工(MISSM)技术,该技术充分利用(111)硅片的晶向分布和各向异性湿法腐蚀的特性。通过在单晶硅片表面制作一系列微型释放窗口来定义结构的轮廓及尺寸,实现在单晶硅片内部选择性可自停止腐蚀技术,制作出不同结构尺寸的腔体。同时,结合不同器件结构设计的需求,缝合微型释放窗口并进行后续工艺制作及最终可动结构释放。该技术采用微创手术式单硅片单面体硅工艺替代传统的表面微机械工艺,制作工艺简单,既具有单硅片单面加工的优势又便于与IC工艺兼容。文章详细讲述了微创手术式三维微机械结构的成型机理和工艺流程,并针对其关键技术进行了系统的分析,取得了令人满意的结果。

The Minimally-invasive-surgery-liked silicon micromachining (MISSM) process

A novel minimally-invasive-surgery-liked silicon micromachining(MISSM)technology is presented in this paper,which take full advantage of the(111)silicon wafer crystal orientation distribution and the characteristics of the anisotropic wet etching.By fabricating serials of releasing mini-holes in one side of the silicon wafer to define the designed structure shape and dimensions,a selective self-stop wet etching technology inside the silicon substrate could be realized,and then,various sizes of the cavities structure can be formed beneath the monocrystalline silicon structure layers with all the boundary walls as {111} planes.Furthermore,according to the requirement for the design of the different device structure,the releasing mini-holes located in the formed monocrystalline structure layer can be sealed to form perfect single-crystal-silicon diaphragm on which subsequent fabrication process can be performed.Finally,the movable structure could be selectively released by etching the diaphragm.The MISSM technology not only has the advantage of single-wafer-based single-sided micromachining but also is compatible with IC fabrication process.In the paper,the formation mechanism of the 3-Dimensions micro-structure fabricated with MISSM technology and relevant fabrication process are described in detail.Then,the key technology is analyzed and satisfying results are achieved.