Dual functionality metamaterial enables ultra-compact, highly sensitive uncooled infrared sensor

Jin Tao,Menglun Zhang,Dejia Meng,Qingrui Yang,Wei Pang,Jingqiu Liang,Guang Zeng,Zhongzhu Liang,David R Smith,Tarik Bourouina,Qing Huo Liu

doi:10.1515/nanoph-2020-0607

Abstract

Abstract Cointegration and coupling a perfect metamaterial absorber (PMA) together with a film bulk acoustic wave resonator (FBAR) in a monolithic fashion is introduced for the purpose of producing ultracompact uncooled infrared sensors of high sensitivity. An optimized ultrathin multilayer stack was implemented to realize the proposed device. It is experimentally demonstrated that the resonance frequency of the FBAR can be used efficiently as a sensor output as it downshifts linearly with the intensity of the incident infrared irradiation. The resulting sensor also achieves a high absorption of 88% for an infrared spectrum centered at a wavelength of 8.2 μm. The structure is compact and can be easily integrated on a CMOS-compatible chip since both the FBAR and PMA utilize and share the same stack of metal and dielectric layers.

Highlights

Jin Tao and Zhongzhu Liang have contributed to this work.Uncooled infrared (IR) sensors are widely used in the fields of medical diagnostics, night vision, biological and chemical threat detection, electrical power system inspection, infrared spectroscopy, and thermal imaging
This paper proposes an uncooled, long-wavelength infrared ultracompact sensor that combines perfect metamaterial absorber (PMA) with film bulk acoustic wave resonator (FBAR), both cointegrated on the same chip, to eventually achieve high absorptivity and high sensitivity at a specific wavelength of 8.2 μm—chosen for demonstration of wavelength selectivity within the atmospheric window
The FBAR is composed of an aluminum nitride (AlN) piezoelectric film sandwiched between two metal electrodes (Mo)

Summary

Introduction

Jin Tao and Zhongzhu Liang have contributed to this work. Uncooled infrared (IR) sensors are widely used in the fields of medical diagnostics, night vision, biological and chemical threat detection, electrical power system inspection, infrared spectroscopy, and thermal imaging. Localized surface plasmon resonance (LSPR) increases the intensity of the electric field at the close vicinity of the sub-wavelength structures, which greatly enhances the efficiency of light–matter interactions This has already important applications in enhanced Raman scattering, sensing and detection [23,24,25,26,27]. This paper proposes an uncooled, long-wavelength infrared ultracompact sensor that combines PMA with FBAR, both cointegrated on the same chip, to eventually achieve high absorptivity and high sensitivity at a specific wavelength of 8.2 μm—chosen for demonstration of wavelength selectivity within the atmospheric window. This study helps solving the contradictory requirements fort high absorptivity and high sensitivity of uncooled infrared sensors, and provides a reference for the cointegration of micro–nano-scale plasmonic PMA onto FBAR structures within CMOS-compatible chips to achieve high-performance infrared devices, in particular the uncooled infrared sensors under consideration in this work

Design and fabrication

Characterization

Discussion

Conclusion