High sensitivity and fast response and recovery times in a ZnO nanorod array/p-Si self-powered ultraviolet detector

Abstract

High quality, vertically aligned ZnO nanorods were grown on a silicon substrate, using microwave-assisted chemical bath deposition with poly (vinyl alcohol)-Zn(OH)2 nanocomposites as seed layer. The structure and surface morphology of the prepared ZnO nanorod arrays were characterized using X-ray diffraction and scanning electron microscopy. The optical properties were assessed using photoluminescence measurements; the results showed a high-intensity UV peak, and a lower intensity, broader visible peak. Upon exposure to 395 nm light at a zero-bias voltage, the UV detector showed a high sensitivity of 8000% and fast response and recovery times of 25 and 22 ms, respectively.

Enhanced Quality, Growth Kinetics, and Photocatalysis of ZnO Nanowalls Prepared by Chemical Bath Deposition

“…The latter generally fixes the pH of the solution at around 6 [16], yielding hydroxyl ions which react with Al to form Al(OH) 4 -. It is now well established that the binding of Al(OH) 4 -to the Zn 2+ terminated surfaces is essential for blocking ZnO growth along the (0001) direction and promoting lateral growth [2,11,12]. With Al wafer and equimolar solution of Zinc nitrate hexahydrate (ZN) and HMTA, Ye et al demonstrated that by increasing pH from 6 to 12 (with ammonium hydroxide, AH), thinner nanowalls could be obtained.…”

Double Role of HMTA in ZnO Nanorods Grown by Chemical Bath Deposition

“…[1][2][3][4][5][6][7][8][9][10][11][12] This is due to both ZnO peculiar properties 13 -large and direct band gap energy of 3.3 eV, high exciton binding energy of 60 meV, high electron mobility, large piezoelectric response -and the attractiveness of synthesizing ZnO NRs via low cost methods based on solution phase growth. Among the bottom-up approaches, solution phase growth methods for nanostructures receive large attention as they ensure high deposition rates on a large variety of substrate, without the need for high temperature or vacuum systems.…”

Electrical and photoresponse properties of graphene oxide:ZnO/Si photodiodes

“…The obtained m value between 0.5 and 1 suggests the presence of continuous distribution of trap levels [25,26]. The sensitivity (S) of the diode having 0.03 GO content was determined by the following relation [27].…”