In situand real-time characterization of metal-organic chemical vapor deposition growth by high resolution x-ray diffraction

To study the effects of Cu/Ba ratio of precursor on YBa2Cu3O7-x (YBCO) film, we have employed the technique of metal-organic chemical vapor deposition to prepare 500 nm thick YBCO films on CeO2/YSZ/Y2O3 (YYC) buffered Ni-W alloy tapes at series of Cu/Ba ratios of precursor. The analysis obtained from X-ray diffraction and scanning electron microscope revealed that the YBCO films crystallized better and became more continuous and denser as Cu/Ba ratio increased from 0.81 to 1.00, yielding that the critical current density (Jc) of YBCO films at 77K and 0T rose from 1.0 MA/cm2 to 1.4 MA/cm2. Moreover, the energy dispersive spectroscopy indicated that the increase in Cu/Ba ratio of precursor made the Cu/Ba ratio of the YBCO film matrix closer to the theoretical value of 1.5. However, for the Cu/Ba ratio of precursor in the range of 1.00~1.21, the crystallization and texture deteriorated severely and many unexpected precipitates of Ba-Cu-O and Cu-O arose, resulting in the dramatic drop of Jc from 1.4 MA/cm2 to 0.1 MA/cm2.

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The Growth and Optimization of InPSb/InGaAs/InAsSb Strained-Layer Superlattice Emitters by Metal Organic Chemical Vapor Deposition

MRS Proceedings ◽

10.1557/proc-379-283 ◽

1995 ◽

Vol 379 ◽

Cited By ~ 2

Author(s):

R. M. Biefeld ◽

S. R. Kurtz

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Chemical Vapor ◽

Organic Chemical ◽

X Ray Diffraction ◽

X Ray ◽

Strained Layer ◽

Metal Organic ◽

Interface Layers ◽

Organic Chemical Vapor Deposition

ABSTRACTWe have prepared InAsSb/InGaAs strained-layer superlattices (SLS's) and InPSb confinement layers using metal-organic chemical vapor deposition (MOCVD) for use as infrared emitters. X-ray diffraction was used to determine lattice matching as well as composition and structure of the SLS's. Photoluminescence linewidth and intensity were used as a measure of the quality of the structures. Typical FWHM were less than 10 meV. The presence of interface layers were indicated by broadened x-ray diffraction peaks for samples grown under non-optimized conditions. Two types of interfacial layers apparently due to a difference in composition at the interfaces were observed with transmission electron microscopy (TEM). The width of the x-ray peaks can be explained by a variation of the interfacial layer thicknesses. Optimized growth resulted in SLS's with narrow x-ray peaks and high radiative efficiency. Room temperature LEDs operating between 4-5 μm have been prepared.

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Metal–Organic Chemical Vapor Deposition Growth and Characterization of InAlGaN Multiple Quantum Wells

Japanese Journal of Applied Physics ◽

10.1143/jjap.48.071001 ◽

2009 ◽

Vol 48 (7) ◽

pp. 071001 ◽

Cited By ~ 2

Author(s):

Yusuke Sakai ◽

Takashi Egawa

Keyword(s):

Chemical Vapor Deposition ◽

Quantum Wells ◽

Vapor Deposition ◽

Chemical Vapor ◽

Organic Chemical ◽

Multiple Quantum ◽

Chemical Vapor Deposition Growth ◽

Metal Organic ◽

Organic Chemical Vapor Deposition

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Deposition of Superconducting Tl-Ba-Ca-Cu-O Phases on Metal Foils by Metal-Organic Chemical Vapor Deposition

MRS Proceedings ◽

10.1557/proc-275-365 ◽

1992 ◽

Vol 275 ◽

Author(s):

D. L. Schulzi ◽

B. Hano ◽

D. Neumayer ◽

B. J. Hinds ◽

T. J. Markst ◽

...

Keyword(s):

Thin Films ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Chemical Vapor ◽

Organic Chemical ◽

X Ray Diffraction ◽

X Ray ◽

Metal Foils ◽

Metal Organic ◽

Organic Chemical Vapor Deposition

ABSTRACTThe synthesis of superconducting Tl-Ba-Ca-Cu-O thin films on metal foils (Au and Ag) by metal-organic chemical vapor deposition (MOCVD) has been investigated. Ba-Ca-Cu-O-(F) films are first prepared via MOCVD using fluorinated “second generation” metal-organic precursors. After an intermediate anneal with water vapor-saturated oxygen to promote removal of F, Tl is introduced by annealing in the presence of a mixture of oxides (Tl2O3, BaO, CaO, CuO) of a specific composition. Characterization of the thin films by scanning electron microscopy, EDX, x-ray diffraction, and variable temperature magnetization measurements has been carried out. High temperature superconductor (HTS) films of Tl2Ba2Ca1Cu2O8−x on Au foil exhibit a magnetically derived Tc = 80K and a high degree of texturing with the crystallite c-axes oriented perpendicular to the substrate surface as evidenced by enhanced (000 x-ray diffraction reflections. Thin film coverage on Ag foil becomes non-contiguous during the (Tl2O3, BaO, CaO, CuO) mixture anneal.

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Well-AlignedIrO2Nanocrystals

Journal of Nanomaterials ◽

10.1155/2007/84845 ◽

2007 ◽

Vol 2007 ◽

pp. 1-17 ◽

Cited By ~ 6

Author(s):

Alexandru Korotcov ◽

Reui-San Chen ◽

Hung-Pin Hsu ◽

Ying-Sheng Huang ◽

Dah-Shyang Tsai ◽

...

Keyword(s):

Vapor Deposition ◽

Chemical Vapor ◽

Organic Chemical ◽

Substrate Effect ◽

X Ray Diffraction ◽

Scanning Electron Microscopy Micrographs ◽

X Ray ◽

Metal Organic ◽

Vertically Aligned ◽

Organic Chemical Vapor Deposition

We review the results of synthesis of well-alignedIrO2nanocrystals (NCs) on sapphire (SA), LiNbO3(LNO), LiTaO3(LTO) substrates via reactive magnetron sputtering and metal-organic chemical vapor deposition. The surface morphology and structural properties of the as-deposited NCs were characterized. Field emission scanning electron microscopy micrographs reveal that NCs grown on SA(100)/LNO(100) are vertically aligned, while the NCs on SA(012)/LTO(012) and SA(110) contain singly and doubly tilted alignments, respectively, with a tilt angle of∼35∘from the normal to the substrates. NCs grown on SA(001) show in-plane alignment with mosaic structure. The X-ray diffraction results indicate that the NCs are (001), (101), and (100) oriented on SA(100)/LNO(100), SA(012)/LTO(012)/SA(110), and SA(001) substrates, respectively. A strong substrate effect on the alignment of theIrO2NCs deposition has been demonstrated. The roles of different substrates in the formation of various textures of nanocrystallineIrO2are studied and the possible mechanisms have been discussed.

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