Temperature effects on the growth and electrical properties of Er 2 O 3 films on Ge substrates. T. Ji 1 , T. X. Nie 1 , J. Cui 1 , Z. B. Fang 2 , X. J. Yang 1 , Y. L. Fan 1 , Z. Y. Zhong 1 , and Z. M. Jiang 1 1 State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, China
Temperature effects on the growth and electrical properties of Er2O3 films on Ge substrates
T. Ji1, T. X. Nie1, J. Cui1, Z. B. Fang2 , X. J. Yang1, Y. L. Fan1, Z. Y. Zhong1, and Z. M. Jiang1
1State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, China
2 Department of Physics, Shaoxing University, Shaoxing 312000, China
Film growth at different temperatures
The film deposited at RT is composed of an Er2O3 layer and an ErGexOy interface layer with a thickness of 5.5 nm; The film grown at 300 ℃ has a mixed structure of Er2O3 and ErGexOy with a much reduced thickness of 2.2 nm; The film grown at 450 ℃ becomes much rougher with voids formed underneath the film, having a mixed structure of two major compounds of Er2O3, GeO and one minor compound of ErGexOy.
Electrical properties of the films
Conventional I-V measurement in macroscopic scale
Tunneling AFM (TUNA) measurement in microscopic scale
The leakage current densities of all the three films are very large in macroscopic scale.
The film grown at 450℃ has much more leaky spots than those grown at RT and 300℃, which may arise from the formation of volatile GeO in the film.