TY - GEN
T1 - Laser assisted molecular beam deposition of high mobility zinc oxide
AU - Li, Meiya
AU - Chokshi, Nehal
AU - Deleon, Robert L.
AU - Tompa, Gary
AU - Anderson, Wayne
PY - 2006
Y1 - 2006
N2 - We have utilized laser assisted molecular beam deposition (LAMBD) to deposit zinc oxide (ZnO) at room temperature. The production of ZnO films via LAMBD utilizes an excimer laser induced ablation plume of zinc in combination with pulsed oxygen gases to create a molecular beam of ZnO clusters. The deposited films have been characterized structurally and electrically in an as deposited state as well as after post deposition excimer laser annealing. The films undergo a clear structural change from a nanoparticle like film to either a microgranular film or a smooth continuous film depending upon the laser annealing power. Al ohmic contacts were made to both as-deposited and laser-annealed ZnO thin films. Thickness and refractive index, chemical composition, and surface morphology of the thin films were analyzed by using ellipsometry, electron spectroscopy for chemical analysis (ESCA), and field emission scanning electron microscopy (FESEM), respectively. Dark current-voltage (I-V), DC photo I-V, Hall-effect, and photoluminescence measurements were employed for testing the device performance. In some cases, the ZnO thin film was changed from n-type into p-type after laser annealing, and photoconductive behavior was clearly seen on the laser-annealed samples, with values of 2.8×10 -4 Ω -1. Also, both samples with and without laser annealing show near-band emission at ∼3.3 eV. Furthermore, the full width at half maximum (FWHM) values of the laser-annealed LAMB ZnO film was reduced from 20.02 nm or 21.68 nm to 18.2 nm when compared with that of non-laser annealed samples. This indicates that the laser annealing provided an improved stoichiometric quality and crystallinity to the ZnO thin films.
AB - We have utilized laser assisted molecular beam deposition (LAMBD) to deposit zinc oxide (ZnO) at room temperature. The production of ZnO films via LAMBD utilizes an excimer laser induced ablation plume of zinc in combination with pulsed oxygen gases to create a molecular beam of ZnO clusters. The deposited films have been characterized structurally and electrically in an as deposited state as well as after post deposition excimer laser annealing. The films undergo a clear structural change from a nanoparticle like film to either a microgranular film or a smooth continuous film depending upon the laser annealing power. Al ohmic contacts were made to both as-deposited and laser-annealed ZnO thin films. Thickness and refractive index, chemical composition, and surface morphology of the thin films were analyzed by using ellipsometry, electron spectroscopy for chemical analysis (ESCA), and field emission scanning electron microscopy (FESEM), respectively. Dark current-voltage (I-V), DC photo I-V, Hall-effect, and photoluminescence measurements were employed for testing the device performance. In some cases, the ZnO thin film was changed from n-type into p-type after laser annealing, and photoconductive behavior was clearly seen on the laser-annealed samples, with values of 2.8×10 -4 Ω -1. Also, both samples with and without laser annealing show near-band emission at ∼3.3 eV. Furthermore, the full width at half maximum (FWHM) values of the laser-annealed LAMB ZnO film was reduced from 20.02 nm or 21.68 nm to 18.2 nm when compared with that of non-laser annealed samples. This indicates that the laser annealing provided an improved stoichiometric quality and crystallinity to the ZnO thin films.
UR - https://www.scopus.com/pages/publications/33747352301
M3 - Conference contribution
AN - SCOPUS:33747352301
SN - 1558998454
SN - 9781558998452
T3 - Materials Research Society Symposium Proceedings
SP - 431
EP - 436
BT - Progress in Semiconductor Materials V - Novel Materials and Electronic and Optoelectronic Applications
T2 - 2005 MRS Fall Meeting
Y2 - 28 November 2005 through 1 December 2005
ER -