Wei Mi

Electrical and optical characterizations of β-Ga2O3:Sn films deposited on MgO (110) substrate by MOCVD

Tin-doped β-Ga2O3 (β-Ga2O3:Sn) films doped with different tin concentrations were deposited on MgO (110) substrates by metal organic chemical vapor deposition (MOCVD) at 700 °C. The effect of doping on the structural, electrical and optical properties of the films was investigated. The 10% Sn-doped film exhibited the best electrical conductivity properties with the lowest resistivity about 5.21 × 10−2 Ω cm, which is over ten orders of magnitude lower than the un-doped film. Micro-structural analysis revealed that the film with 10% Sn content had a clear in-plane relationship of β-Ga2O3 (100) ‖ MgO (110) with β-Ga2O3 (01) ‖ MgO (111). The average transmittance of the samples in the visible range exceeded 87% and the optical band gap of the films varied from 4.12 to 4.80 eV.

Twin structures of epitaxial SnO2 films grown on a-cut sapphire by metalorganic chemical vapor deposition

SnO2 films have been grown on a-cut (112¯0) sapphire substrates by metalorganic chemical vapor deposition. X-ray diffraction and transmission electron microscopy were employed to characterize the epitaxial relationship and film structure. The films were (101) oriented with pure rutile structure. The in-plane relationship was determined to be SnO2 [010]//Al2O3 [0001] and SnO2 [101¯]//Al2O3 [11¯00]. There are three kinds of {101} twins in the SnO2 film. These twins caused high density of planar defects in the film and slight misorientation of the growth plane. The film/substrate interface was flat, while the film surface was rough with steps and inclinations.

Structural and Optical Properties of α-Ga2O3 Films Deposited on Sapphire (10‾10) and (01‾12) Substrate by MOCVD

Ga2O3 thin films were grown on sapphire m-cut () and r-cut () orientations substrates at different temperatures by metal-organic chemical vapor deposition. Structural and optical properties of the Ga2O3 films were investigated including the influence by annealing for the obtained films. The Ga2O3 films on sapphire () and () substrate are α-Ga2O3. The crystallization of the films decreases after annealed at 900 °C. The average transmittance of the samples in the visible wavelength range was over 86% and the optical band gap Eg was about 4.755.15 eV. The Eg of the samples increases after annealing at 900 °C.

Structural and optical properties of Al2xIn2−2xO3 films prepared by metal-organic chemical vapor deposition

Tunable band gap Al2xIn2−2xO3 films with different compositions x[Al/(Al + In) atomic ratio] were grown on MgO (110) substrates by the metal organic chemical vapor deposition (MOCVD) method at a temperature of 700 °C. The effects of different Al concentrations on the structural and optical properties of the obtained films were discussed in detail. The film deposited with an Al concentration of x = 0.1 showed single crystalline bixbyite In2O3 structure with Al0.2In1.8O3 (110)‖MgO (110), while the films with x = 0.3 and 0.5 had polycrystalline structures, and the sample prepared with x = 0.9 exhibited γ-Al2O3 structure. The transmittances of all the samples exceeded 80% in the visible region. The optical absorption edges of the films shifted to short wavelength, and the bandgap of the prepared films could be monotonously modulated from 3.73 eV to 5.82 eV as the Al concentration increased from 0.1 to 0.9.

Preparation and characterization of Al{sub 2x}In{sub 2−2x}O{sub 3} films deposited on MgO (1 0 0) by MOCVD

Highlights: • Ternary Al{sub 2x}In{sub 2−2x}O{sub 3} alloy films were deposited on MgO (1 0 0) by MOCVD. • The microstructure of the Al{sub 2x}In{sub 2−2x}O{sub 3} films were studied upon HRTEM. • Al{sub 2x}In{sub 2−2x}O{sub 3} alloy films exhibited great optical transparency in the visible wavelength range. • The band gap of the Al{sub 2x}In{sub 2−2x}O{sub 3} films can be modulated by controlling the Al contents in the samples. - Abstract: The ternary Al{sub 2x}In{sub 2−2x}O{sub 3} films with different compositions x[Al/(Al + In) atomic ratio] have been fabricated on the MgO (1 0 0) substrates by the metal organic chemical vapor deposition (MOCVD) method. The influence of different Al contents on the structural, optical and electrical properties of Al{sub 2x}In{sub 2−2x}O{sub 3} films has been studied. The structural studies reveal a change from single crystalline structure of cubic In{sub 2}O{sub 3} to amorphous as the Al content increases. The average transmittances of all samples in the visible range are over 80%. The optical band gap is observed to increase monotonically from 3.67 to 5.38 eV as the Al content increases from 0.1 to 0.9.

Structure and Optical Properties of Epitaxial Indium Oxide Films Deposited on Y-Stabilized ZrO2 (111) by MOCVD

Indium oxide (In2O3) films have been deposited on Y-stabilized ZrO2 (YSZ) (111) substrates, at temperatures from 500°C to 700°C, by metal–organic chemical vapor deposition. Structural analysis indicated that all the films were cubic bixbyite In2O3 with an out-of-plane relationship of In2O3 (222)||YSZ (111). Crystal quality was best for the film prepared at 600°C. The microstructure of this film was investigated by high-resolution transmission electron microscopy. A theoretical model is proposed for the mechanism of growth, and the in-plane epitaxial relationship of the single crystalline In2O3 film on the YSZ (111) substrate was shown to be In2O3

Characterization of β-Ga2O3 thin films on sapphire (0001) using metal-organic chemical vapor deposition technique

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Epitaxial growth of Ga2O3 thin films on MgO (110) substrate by metal–organic chemical vapor deposition

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