Design and fabrication of low-deformation micro-bolometers for THz detectors
Ziji Liu, Zhiqing Liang, Wen Xuan Tang, Xiangdong Xu
Abstract
Control of the residual film stress to the desired levels is critical for the design and fabrication of high-quality micro-bolometers for terahertz (THz) detectors. In this work, a stress equivalent method was employed to investigate the deformations of the suspended multi-layer micro-bolometers. According to the orthogonal calculation results obtained by a design of experiment (DOE) method, the optimal residual stress for each layer was simulated, by which high-quality micro-bolometers with low deformation were designed. Furthermore, 384 × 288 THz focal plane arrays constructed by the as-designed micro-bolometers were successfully fabricated. Particularly, the as-fabricated micro-bolometers have uniform morphologies, smooth surfaces, low deformations of 0.063 μm, all of which are accordance with the simulated results and suggest suitable applications of the designed micro-bolometers in THz detecting.