Formation of the Microcrystalline Structure in LiNbO3 Thin Films by Pulsed Light Annealing

Authors R.N. Zhukov1 , T.S. Ilina1, E.A. Skryleva1, B.R. Senatulin1, I.V. Kubasov1 , D.A. Kiselev1 , G. Suchaneck2 , M.D. Malinkovich1 , Yu.N. Parkhomenko1 , A.G. Savchenko1

1National University of Science and Technology "MISiS", 4, Leninskiy Prosp., 119049 Moscow, Russian Federation

2TU Dresden, Solid State Electronics Laboratory, 01062 Dresden, Germany

Issue Volume 10, Year 2018, Number 2
Dates Received 11 December 2017; revised manuscript received 28 April 2018; published online 29 April 2018
Citation R.N. Zhukov, T.S. Ilina, E.A. Skryleva, et al., J. Nano- Electron. Phys. 10 No 2, 02009 (2018)
PACS Number(s) 77.80.Dj, 68.55. – a, 77.55.H –
Keywords Lithium niobate (3) , Li/Nb ratio, rf-magnetron sputtering (2) , Post-growth infrared rapid annealing, Piezoresponse force microscopy (4) , X-ray photoelectron spectroscopy (3) .

LiNbO3 thin films with a thickness of 200 nm were deposited onto Al2O3 substrate by RF-magnetron sputtering technique without intentional substrate heating. The results demonstrate that post-growth infrared pulsed light annealing of the amorphous LiNbO3 films leads to the formation of two phases, LiNbO3 and LiNb3O8. After annealing at temperatures of 700 to 800 °C, the percentage of the non-ferroelectric phase LiNb3O8 was minimal. The surface composition of the films annealed at different temperatures was examined by X-ray photoelectron spectroscopy. Piezoresponse force microscopy was used to study both the vertical and the lateral polarization and to visualize the piezoelectric inactivity of LiNb3O8 grains. A comparison of the results of PFM and XPS measurements revealed that there is a correlation between the fraction of the piezoelectric phase and the film composition: At an annealing temperature higher than 850 °C, the atomic ratio of lithium to niobium decreases compared to the initial value along with a decrease of the fraction of the piezoelectric phase.

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