Authors: R.W. Johnstone and M. Parameswaran
Affilation: Simon Fraser University, Canada
Pages: 412 - 415
Keywords: reflow fabrication, micro-optics, refractive lenses
Our paper will describe a new method of fabricating refractive optical components for free-space micro-optical systems. The seminal paper on this topic was Pister et al , in which hinges were used to demonstrate several novel types of surface-micromachined components, including several optical components. In particular, the method has been used to construct mirrors and diffractive optics      . Reflow microfabrication is a modification of standard surface-micromachining techniques, and does not limit the construction of structures available using conventional surface-micromachining. In our proposed fabrication process, the wafers undergo a complete surface-micromachining process with at least two moveable structural layers, such as PolyMUMPs™. An additional layer, called the ‘optical’ layer, is deposited upon the wafer and patterned, before the release step. This layer is composed of the material that will be used to construct the refractive components. In addition to its optical properties, the material for the ‘optical’ layer is chosen to have a melting point below the other structural materials in the surface-micromachining process. Processing then continues with the release step and the assembly of 3D structures .