3D Optical microstructure fabrication and its bonding to micro IR detector using elastomeric polymer

This paper describes polidimethylsiloxane(PDMS) based bonding for assembly of microstructure device, an UV lithography applications for fabricating a 3-dimensional (3D) feed-horn-shaped structure mold array, and obtaining parallel light by using a mirror-reflected parallel-beam illuminator (MRPBI) system. A 3D feed-horn-shaped micro-electro-mechanical systems (MEMS) antenna has some attractive features for array applications, which can be used to improve microbolometer performance and to enhance the optical efficiency for thin film transistor-liquid crystal display (TFT-LCD) and other display devices but currently, MEMS technology has faced many difficulties in the fabrication of a 3D feed-horn-shaped MEMS antenna array itself. The purpose of this paper is to propose a new fabrication method to realize a 3D feed-horn-shaped MEMS antenna array by using a mirror-reflected parallel-beam illuminator (MRPBI) System with a very slowly rotated, inclined x-y-z stage. With a conventional UV lithography apparatus, it is very difficult to fabricate high-aspect-ratio structures (HARS) because a typical UV lithography apparatus cannot produce perfectly parallel light. From a theoretical analysis, a columnar illuminator over 6 m in height is required to achieve parallel light, but generally a laboratory height is not 6 m. Also, a novel method of lithography was tried to make a 3D structure array by exposing a planar wafer to the generated parallel light and rotating an inclined x-y-z stage at an ultra-slow rate. An optimization of the 3D structure array can be achieved by simulating a 3D feed-horn MEMS antenna. The feasibility of fabricating both a 3D feed horn MEMS antenna and assembly of detector with 3D feed-horn MEMS antenna was demonstrated. As a result, it seems possible to use a 3D feed-horn-shaped MEMS antenna to improve microbolometer performance and to fabricate several optical microstructure applications.