Research progress of high-performance flexible wide-spectrum image sensor in Chinese Academy of Sciences

[China Instrument Network Instrument R&D] Recently, the National Semiconductor Superlattice State Key Laboratory Shen Guozhen of the Institute of Semiconductors, Chinese Academy of Sciences has made new progress in the study of flexible broad-spectrum imaging. Related research results were published on Advanced Functional Materials.

Wide-spectral imaging technology can usually complete detection and imaging of an environment or an object that contains multiple bands (such as ultraviolet, visible, near-infrared, mid-infrared, far-infrared, etc.). In a complex environment, wide-spectrum imaging technology has enormous advantages in target detection and recognition over single-band imaging because of its ability to obtain multiple bands of information. Therefore, this technology has been widely used in biomedicine, criminal investigation, mineral exploration, optical communication and all-weather monitoring. However, conventional wide-spectrum image sensors are generally based on rigid substrates such as silicon, which have the disadvantages of being difficult to bend, poor impact resistance, and being difficult to carry, and can not meet the current social diversified application scenarios and requirements within a certain range. With the increasing demand for flexible electronic devices, a variety of flexible sensor devices have been developed, such as flexible temperature sensors, pressure sensors, and gas sensors. The development of flexible and wide-spectrum image sensors has been applied to satisfy people's diverse application needs. Significance.

In this context, Li Guodong, a doctoral student of the Shen Guozhen group, and Yan Zheng, an assistant researcher, used a two-step vapor deposition method to modify the narrow band gap p-type SnS on the surface of a wide bandgap n-type Zn2SnO4 (~3.6eV) nanowire. 1.3eV) Quantum dots, and a flexible PET plastic film substrate, developed a flexible UV-visible-near-infrared broad-spectrum image sensor. It was found that SnS QD-modified Zn2SnO4 nanowire devices have a higher UV response and broaden the spectral response range to near infrared than pure Zn2SnO4 nanowire devices, thanks to the Zn2SnO4 nanowires and SnS quantum dots. The formation of quasi-II heterojunctions and narrow band gaps of SnS quantum dots. Because the device is fabricated on a flexible PET film substrate, the Zn2SnO4 nanowire has excellent flexibility and a radius of curvature as small as micrometers because of its ultra-high aspect ratio, so that the device has excellent bendability and Mechanical stability, no significant performance degradation occurred even after 5000 cycles of bending. Under bending conditions, the prepared flexible broad-spectrum image sensor can clearly identify the target pattern composed of red light and white light, indicating its potential application in the future of flexible wide-spectrum imaging. This work provides a new design idea and feasibility process for obtaining high performance flexible wide-spectrum image sensors.

This work was supported by the National Outstanding Youth Science Foundation, the Frontier Science Key Research Project of the Chinese Academy of Sciences, and the Beijing Natural Science Foundation.

(Original Title: Research Progress of High-Performance Flexible Broad-spectrum Imaging by Semiconductor Institute)