by Rehab Ramadan, Jean Gabriel Simiz, María Dolores Ynsa and Miguel Manso Silván
Abstract:
The sol-gel process allows the high throughput formation of transition metal oxide thin films. Microwave plasma annealing (MwPA) treatments have been performed on thin films of two different transition metal oxides, Ta2O5 and ZnO, selected as representatives of covalently and strongly ionic bonded oxides, respectively. Ta2O5 has been explored as a dielectric barrier for porous silicon structures. The main limitation of the sol-gel spin coating in this case is the surface roughness of the coating, which is highly improved upon Ar MwPA. The treatment leads additionally to a microstructural activation and interface development comparable to a 500 °C thermal annealing. The MwPA of ZnO is a quasi-equivalent process to a 200 °C thermal annealing, preventing grain growth and promoting nanocrystalline phases. This is suggested to have a direct impact on the optical and electronic properties of the ZnO films. The MwPA films show wider optical band gap than thermally annealed ones. An impedance analysis further shows that the MwPA ZnO films present lower equivalent resistance and higher equivalent capacitance than the thermal films. These results are promising for the development of new processing routes for widely demanded transition metal oxide thin films.
Reference:
Rehab Ramadan, Jean Gabriel Simiz, María Dolores Ynsa and Miguel Manso Silván, “Microwave plasma annealing of sol-gel deposited tantalum oxide and zinc oxide films”, Vacuum, vol. 149, pp. 336–342.
Bibtex Entry:
@article{ramadan_microwave_2018, title = {Microwave plasma annealing of sol-gel deposited tantalum oxide and zinc oxide films}, volume = {149}, issn = {0042-207X}, url = {http://www.sciencedirect.com/science/article/pii/S0042207X1731360X}, doi = {10.1016/j.vacuum.2018.01.007}, abstract = {The sol-gel process allows the high throughput formation of transition metal oxide thin films. Microwave plasma annealing (MwPA) treatments have been performed on thin films of two different transition metal oxides, Ta2O5 and ZnO, selected as representatives of covalently and strongly ionic bonded oxides, respectively. Ta2O5 has been explored as a dielectric barrier for porous silicon structures. The main limitation of the sol-gel spin coating in this case is the surface roughness of the coating, which is highly improved upon Ar MwPA. The treatment leads additionally to a microstructural activation and interface development comparable to a 500 °C thermal annealing. The MwPA of ZnO is a quasi-equivalent process to a 200 °C thermal annealing, preventing grain growth and promoting nanocrystalline phases. This is suggested to have a direct impact on the optical and electronic properties of the ZnO films. The MwPA films show wider optical band gap than thermally annealed ones. An impedance analysis further shows that the MwPA ZnO films present lower equivalent resistance and higher equivalent capacitance than the thermal films. These results are promising for the development of new processing routes for widely demanded transition metal oxide thin films.}, urldate = {2019-01-24}, journal = {Vacuum}, author = {Ramadan, Rehab and Simiz, Jean Gabriel and Ynsa, María Dolores and Manso Silván, Miguel}, month = mar, year = {2018}, keywords = {Annealing, Microwave plasma, Optoelectronics, Sol gel, Transition metal oxides}, pages = {336--342}, file = {ScienceDirect Full Text PDF:E:\cmam_papers\files\1701\Ramadan et al. - 2018 - Microwave plasma annealing of sol-gel deposited ta.pdf:application/pdf;ScienceDirect Full Text PDF:E:\Usuarios\Administrator\Zotero\storage\2BEUFSF3\Ramadan et al. - 2018 - Microwave plasma annealing of sol-gel deposited ta.pdf:application/pdf;ScienceDirect Snapshot:E:\cmam_papers\files\1700\S0042207X1731360X.html:text/html;ScienceDirect Snapshot:E:\Usuarios\Administrator\Zotero\storage\ZLQFTK8W\S0042207X1731360X.html:text/html;SCOPUS Snapshot:E:\Usuarios\Administrator\Zotero\storage\P8IYEHAB\display.html:text/html}, }