Fabrication of Infrared Thermal Emitters with Cross-Shaped Mesh Filters by CMOS Process

• Main Authors: Po-Chun Chan, 詹博鈞
• Other Authors: San-Liang Lee
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/yrv282

碩士 === 國立臺灣科技大學 === 電子工程系 === 107 === Far-infrared (FIR) thermal emitters are useful in medical applications. The goal of this work is to make a high-efficiency light source in a simple and cheap way, and to realized light sources of 8-12 μm wavelength range for medical applications. We first analyze the issues of the previous work, and then design the thermal emitters to have improved thermal uniformity and luminous efficiency. The band-pass filtering is verified by varying two parameters in the design. We successfully fabricate the thermal emitters using the 0.35-μm CMOS standard process to achieve good process stability, low cost, and mass manufacturing. In this work, we redesign the shape and layout of the heating wire. The spacing between the spiral wires is gradually changed to achieve uniform surface temperature distribution under heating. We reduce the area covered by the metal layer and realize the FIR emitters with higher emissivity and luminous efficiency. The FIR component with a heating area of only 2.63 mm2 can achieve a radiant efficiency of 3.77 × 10-4, total emitting power of 0.799 mW, and output power per unit area of 0.304 mW/mm2. The periodic cross-hole meshed filter is verified by both simulation and experiments. The filter shows a 14-μm center frequency with high transmission. The hanging chips are found to isolate the heat transfer on the heating area and significantly increase the radiant power and efficiency.