Heat treatment effect on performance of printed ZnO UV photodetector

• Main Author: Koh, Edmund Jun Guo
• Other Authors: Du Hejun
• Format: Final Year Project
• Language: English
• Published: 2018
• Subjects: DRNTU::Engineering::Nanotechnology
• Online Access: http://hdl.handle.net/10356/74558
• Institution: Nanyang Technological University

The use of additive manufacturing has been on the rise. One of which is the usage of Inkjet-printing. The main objective of this project was to use all-inkjet printing method to make a photodetector using ZnO and to study the annealing effects to ZnO photodetector performance. After printing the ZnO on the substrate, annealing needs to be done for the photodetector to be ready for use. Before annealing, the unannealed sample required a rise time of Tr1=2.31893 s and the annealed sample required a rise time of Tr1=12.95526 s. From the readings of the photocurrent, the magnitude of the photocurrent for the unannealed sample was lower than the annealed sample by one order of magnitude. This was due to the lowering of the band bending level which allowed the electrons to move in and out of the grain boundaries easily as compared to before annealing, hence able to capture higher readings of UV light.