A Technique for Achieving Precision Cross Sections of Released Surface Micromachined Structures

Surface micromachining of mechanical sensors is quickly becoming a part of integrated circuit technology. The accurate and reliable analysis of these sensors is critical to the development of such devices and the maintenance of quality in the fabrication process. One aspect of sensor analysis is cross section sample preparation for electron microscopy. This presents a new challenge to the analyst because these sensors require nontraditional sample preparation techniques. This paper presents a method of encapsulating surface micromachined sensors with thermosetting epoxy and a thin glass cover slip. Traditional precision polishing techniques are then used to achieve accurate and reliable cross sections.