title: Improved Photo-Detection Using Zigzag TiO2 Nanostructures as an Active Medium.
abstract: Zigzag TiO2 nanostructures were fabricated using oblique angle deposition technique. The field emission gun-scanning electron microscope (FEG-SEM) image shows that the TiO2 zigzag nanostructures were ~500 nm in length. Averagely two times enhanced UV-Vis absorption was recorded for zigzag structure compared to perpendicular TiO2 nanowires. The main band transition was observed at ~3.4 eV. The zigzag TiO2 exhibited high turn on voltage (+11 V) than that of nanowire (+2 V) detector under dark which were reduced to +0.2 V and +1.0 V under white light illumination, respectively. A maximum ~6 fold photo-responsivity was observed for the zigzag TiO2 compared with nanowire device at + 1.0 V applied potential. The maximum photo-responsivity of 0.36 A/W at 370 nm was measured for the zigzag TiO2 detector. The TiO2 zigzag detector showed slow response with rise time of 10.2 s and fall time of 10.3 s respectively. The UV (370 nm) to visible (450 nm) wavelength rejection ratio of photo-responsivity was recorded ~4 times for the detector.
authors.forename: A K
authors.initials: AK
authors.lastname: Tiwari
authors.forename: A
authors.initials: A
authors.lastname: Mondal
authors.forename: B K
authors.initials: BK
authors.lastname: Mahajan
authors.forename: B
authors.initials: B
authors.lastname: Choudhuri
authors.forename: T
authors.initials: T
authors.lastname: Goswami
authors.forename: M B
authors.initials: MB
authors.lastname: Sarkar
authors.forename: S
authors.initials: S
authors.lastname: Chakrabartty
authors.forename: C
authors.initials: C
authors.lastname: Ngangbam
authors.forename: S
authors.initials: S
authors.lastname: Saha