Fabrication of beam structures with micro-scale cross-sections and meso-scale spans

Abstract

To allow testing of micro-scale aerodynamics, a process was created to manufacture beam structures that combine spans of 1 cm with a cross-section of 5 µm by 100 µm. The structural considerations limiting the fabrication of a structure combining macro-scale spans with a micro-scale cross-section are analyzed. Limiting considerations include forces during operation, fluid forces during release, vibrational limitations and beam buckling. Based on these results, a fabrication process for creating a beam structure for large spans without support structures is devised, incorporating the use of back-side etches and extra handling wafers to avoid stiction. This process is used to successfully fabricate the desired structure.