BaTiO3 Thin Films for Electro-optic and Non-linear Optical Applications

1995 ◽  
Vol 415 ◽  
Author(s):  
B. A. Block ◽  
B. W. Wessels

ABSTRACTEr-doped BaTiO3 thin films have been investigated as a candidate for an optically active waveguide medium. Epitaxial layers were prepared by metal-organic chemical vapor deposition at low pressure. The properties of the characteristic Er3+ luminescence transition at 0.8 eV have been investigated for epitaxial Er doped BaTiO3 thin films for various Er concentrations. The photoluminescent intensity was found to increase by a factor greater than 500 when the doping level was increased from 1 × 1020 cm−3 to 2.2 × 1021cm−3, indicating that concentration quenching was not significant at the highest doping levels. A complex emission spectra was observed and was attributed to the multi-site substitution of Er in BaTiO3. Transient decay measurements revealed a 7 ms radiative lifetime for the 0.80 eV transition that was independent of concentration.

2004 ◽  
Vol 449-452 ◽  
pp. 997-1000 ◽  
Author(s):  
Gwang Pyo Choi ◽  
Yong Joo Park ◽  
Whyo Sup Noh ◽  
Jin Seong Park

Tin oxide thin films were deposited at 375 °C on α-alumina substrate by metal-organic chemical vapor deposition (MOCVD) process. A number of hillocks on the film were formed after air annealing at 500 °C for 30 min and few things in N2 annealing. The oxygen content and the binding energy after air annealing came to close the stoichiometric SnO2. The cauliflower hillocks of the film seem to be formed by the continuous migration of crystallites from a cauliflower grain on the substrate to release the stress due to the increase of oxygen content and volume.


2007 ◽  
Vol 515 (5) ◽  
pp. 2921-2925 ◽  
Author(s):  
Chunyu Wang ◽  
Volker Cimalla ◽  
Genady Cherkashinin ◽  
Henry Romanus ◽  
Majdeddin Ali ◽  
...  

2012 ◽  
Vol 1439 ◽  
pp. 109-114
Author(s):  
XinYi Chen ◽  
Alan M. C. Ng ◽  
Aleksandra B. Djurišić ◽  
Chi Chung Ling ◽  
Wai-Kin Chan ◽  
...  

ABSTRACTLight-emitting diodes (LEDs) based on p-GaN/ZnO heterojunction were fabricated. GaN was deposited on sapphire using metal-organic chemical vapor deposition (MOCVD), and two kinds of ZnO i.e. ZnO thin film deposited by sputtering and ZnO nanorods (NRs) grown by hydrothermal method were used as n-type layer respectively. MgO film with the thickness around 10 nm was deposited by electron-beam deposition to act as an interlayer between GaN and ZnO. Photoluminescence, electroluminescence and I-V curves were measured to compare the properties of GaN based heterojunction LEDs with different architectures. The existence of MgO interlayer as well as the morphology of ZnO obviously influenced the electrical and optical properties of GaN based LEDs. The effect of MgO interlayer on ZnO growth, properties and I-V curves and emission spectra of LEDs is discussed in detail.


2003 ◽  
Vol 42 (Part 1, No. 5A) ◽  
pp. 2839-2842 ◽  
Author(s):  
Jeong Hoon Park ◽  
Kug Sun Hong ◽  
Woon Jo Cho ◽  
Jang-Hoon Chung

1994 ◽  
Vol 9 (7) ◽  
pp. 1721-1727 ◽  
Author(s):  
Jie Si ◽  
Seshu B. Desu ◽  
Ching-Yi Tsai

Synthesis of zirconium tetramethylheptanedione [Zr(thd)4] was optimized. Purity of Zr(thd)4 was confirmed by melting point determination, carbon, and hydrogen elemental analysis and proton nuclear magnetic resonance spectrometer (NMR). By using Zr(thd)4, excellent quality ZrO2 thin films were successfully deposited on single-crystal silicon wafers by metal-organic chemical vapor deposition (MOCVD) at reduced pressures. For substrate temperatures below 530 °C, the film deposition rates were very small (⋚1 nm/min). The film deposition rates were significantly affected by (i) source temperature, (ii) substrate temperature, and (iii) total pressure. As-deposited films are carbon free. Furthermore, only the tetragonal ZrO2 phase was identified in as-deposited films. The tetragonal phase transformed progressively into the monoclinic phase as the films were subjected to a high-temperature post-deposition annealing. The optical properties of the ZrO2 thin films as a function of wavelength, in the range of 200 nm to 2000 nm, were also reported. In addition, a simplified theoretical model which considers only a surface reaction was used to analyze the deposition of ZrO2 films. The model predicated the deposition rates well for various conditions in the hot wall reactor.


Sign in / Sign up

Export Citation Format

Share Document