DNA-CTMA/a-Si: Hbio-hybrid photodiode: A light-sensitive photosensor

Recently, considerable interest have occurred in the development of an organic-inorganic-based biohybrid photodiodes (Bio-HPDs) with metal-free, eco-friendly, and cost-competitive features for lightsensitive devices. This paper reports a bio-inspired optical absorber material for the fabrication of BioHPDs using n-type hydrogenated amorphous silicon (a-Si: H) and a natural deoxyribonucleic acid (DNA)-cetyltrimethylammonium chloride (CTMA) biomaterial. a-Si: H is inexpensive and abundant, and DNA-CTMA is metal-free and eco-friendly. A DNA-CTMA coating on n-type a-Si: H leads to a chemically stable material with increased absorption and effective ties of dangling bonds and interface state density. Analysis results showed that the rectification ratio (RR) of the Bio-HPD is found to be 4 times higher than reference PD. This indicates that the effective RR is improved by the DNA-CTMA layer since it creates molecular charge interactions between DNA-CTMA layer and a-Si: H substrate. Moreover, Bio-HPD shows a light photosensitivity (Iphoto/Idark) of 474 with more reliable and has longer life time. In addition, the formation and feasible charge transport mechanisms are discussed. This biomaterial can be used for the development of commercially viable and environmentally safe large-scale Bio-HPDs applications. (C) 2017 Elsevier B. V. All rights reserved.