The Polymer Society of Korea

Abstract

Multispectral short-wave infrared (SWIR) photodetection is highly desirable for applications like night vision and quality inspection. Colloidal quantum dots (QDs) are a promising, low-cost alternative to conventional semiconductors due to their size-tunable properties. We demonstrate a multispectral SWIR photodetector using four sizes of heavy-metal-free Ag₂Te QDs, patterned side-by-side via a direct photopatterning process. The resulting pixels show distinct responsivities at distinct wavelengths of 1150, 1350, 1550, and 1800 nm. By leveraging the unique photoresponse of each of the four QD channels, our device can identify SWIR wavelengths without a spectrometer—a capability not possible with single-size QD devices. This approach enables the creation of monolithically integrated, planar photodetector arrays where pixels for different wavebands are precisely patterned and independently addressable on a single chip.