Highly aligned organic microwire crystal arrays for high-performance polarization-sensitive photodetectors and image sensors

Abstract

Organic semiconductors with excellent optoelectronic properties are important building blocks for high-performance organic devices. Patterning organic crystals with high precision and accurately positioning them at the target position are major challenges for integrated devices. However, uncontrollable dewetting of the conventional solution method leads to as-prepared micro-nanocrystals with high defect-state density, low crystalline quality, and disordered distribution, which impair the uniformity of the device performance and limit integration. By regulating the solution position with a template and guiding the solution flow direction under gravity, aligned organic microwire arrays and polygonal patterns were fabricated. The polarization-sensitive photodetector exhibited responsivity up to 1234 A W−1, linear dynamic range of 148 dB, Iphoto/Idark of 104, response time as low as 1.1 ms, and dichroic ratio up to 2.1. Given the homogeneity of microwire arrays, the device-to-device variation was reduced to 3.58%, resulting in high-quality imaging. This study provides new insights into organic micro/nanocrystal patterning and device integration.