Study of MXene Ti₃C₂T_x quantum dot thin film on quartz bulk acoustic wave uncooled infrared sensors

Abstract

The infrared absorption efficiency is essential for an infrared sensor. We propose a quartz bulk acoustic wave (BAW) uncooled infrared sensor coated with MXene quantum dot film. The infrared detection is realized by measuring the resonant frequency of a Y-cut quartz BAW sensitive unit. An infrared sensor is fabricated by MEMS process, then the MXene quantum dot film is coated through the spin coating technology. The mechanism of infrared absorption enhancement is analyzed. Test results show that after coating the film, the responsivity (R) of the sensor increased by nearly 41% at a wavelength of 830nm, from 10.88MHz/W to 15.28 MHz/W. The quartz BAW infrared sensor combined with MXene quantum dots film has the potential of high-performance infrared detection.

Terahertz communication: detection and signal processing

“…By separating the sensitive and vibrating elements into two parts, signal conversion can be effectively enhanced. In recent years, AlN [100], LiNbO3 [101], metal [99], quartz [102], and SiN [103] have received widespread attention as IR absorption and vibrating elements because of their high IR absorption rates and high sensitivities in terms of the temperature change. In addition to common IR-sensitive materials, Qian et al [104] added a layer of ultrathin graphene on AlN, as shown in figure 7, which not only shows a resonant frequency of 307 MHz and quality factor of 450% of the original but also significantly improves the IR absorption rate based on the subwavelength thickness of the transparent graphene film, increasing it by ten times at 5 µm and possibly a hundred times at 3.4 µm.…”