A Front-Side Microfabricated Tiny-Size Thermopile Infrared Detector With High Sensitivity and Fast Response
A Front-Side Microfabricated Tiny-Size Thermopile Infrared Detector With High Sensitivity and Fast Response
复制标题
一种高灵敏度、快速响应的前端微加工微型热电堆红外探测器
DOI：
10.1109/ted.2019.2903589
复制
发表时间：
2019-05-01
影响因子：
3.1
通讯作者：
Li, Xinxin
中科院分区：
文献类型：
--
作者：
Li, Wei;Ni, Zao;Li, Xinxin
本文报道了一种新型微型（ $116\,\,\mu \text {m} \times 134\,\,\mu \text{m}$ ）单晶硅/铝红外（IR）热电堆探测器，该探测器仅从（111）晶圆的正面进行微机械加工，用于 IC 代工兼容的低成本制造。该微型探测器由六个串联的 p 硅/铝热电偶组成，与传统的多晶硅/铝探测器相比，它们具有显着更高的塞贝克系数和更低的噪声。通过所提出的对称螺旋结构，可以在微小的传感区域内扩大热电偶腿的长度以及探测器的热阻。通过优化两个热电材料层的横截面积，提高了比探测率（ $D^{\ast }$ ），这比传统的数学分析方法更实际有效。该器件采用新颖的单面微加工技术在 (111) 晶圆 [而不是普通 (100) 晶圆] 上制造。测试结果表明，探测器实现了342 V/W的超高响应度和0.56 ms的超短响应时间。许多热电堆检测单元具有体积小、成本低、高性能的单点检测功能，可以集成到红外焦平面阵列（IRFPA）中以实现高分辨率成像。
This paper reports a novel tiny-sized ( $116\,\,\mu \text {m} \times 134\,\,\mu \text{m}$ ) single-crystalline silicon/aluminum infrared (IR) thermopile detector, which is micromachined only from the front side of (111) wafer for IC-foundry compatible low-cost manufacturing. The tiny-sized detector consists of six serially connected p-silicon/aluminum thermocouples that show significantly higher Seebeck coefficient and lower noise compared with the traditional poly-silicon/aluminum counterparts. With the proposed symmetric helical structure, the length of thermocouple leg length as well as the thermal resistance of the detector can be enlarged within the tiny sensing area. Specific detectivity ( $D^{\ast }$ ) is improved by optimizing the cross-sectional area of the two thermoelectric-material layers, which is more practically effective than traditional mathematic analysis methods. The device is fabricated in a (111) wafer [instead of normal (100) wafer] by using a novel single-side micromachining technique. The testing results show that the detector achieves an ultrahigh responsivity of 342 V/W and ultrashort response time of 0.56 ms. Featuring tiny-size, low-cost, and high-performance single-point detection, many thermopile detecting units can be integrated into an IR focal-plane array (IRFPA) for high-resolution imaging.