Influence of substrate surface energy and surfactant on crystalline morphology and surface defect density in hydrothermally-grown ZnO nanowires

ABSTRACTThe growth of a-Si:H and the resulting weak bond and defect formation mechanism is analysed in terms of the adsorbed Sill3 model of growth. It is found that this model describes the surface processes well, but it needs further development to correctly describe the temperature dependence of the formation of defects and weak bonds, since the surface defect density decreases monotonically with temperature and does not show a minimum near 250C. We show that the experimentally observed increase in hydrogen content, weak bond and defect density at lower deposition temperatures can be accounted for by a hydrogen evolution reaction from H2* sites.

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LaTiO2N nanopowders (NPs) with low surface defect density via nitridation of flame made NPs retaining simple perovskite structure

Dalton Transactions ◽

10.1039/d1dt03687d ◽

2022 ◽

Author(s):

Yoshiyuki Abe ◽

Richard M. Laine

Keyword(s):

Optical Absorption ◽

Absorption Edge ◽

Perovskite Structure ◽

Surface Defect ◽

Defect Density ◽

Optical Absorption Edge ◽

Surface Defect Density

LaTiO2N NP synthesized from flame made LaTiO3 NP exhibits less absorption background above the optical absorption edge than that synthesized from flame made La2Ti2O7 NP, suggesting a low surface defect density.

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Influence of substrate surface morphology on defect generation during silicon carbide single crystal growth

MRS Proceedings ◽

10.1557/proc-719-f8.12 ◽

2002 ◽

Vol 719 ◽

Author(s):

Myung Yoon Um ◽

Jae Kyeong Jeong ◽

Bum Seok Kim ◽

Hoon Joo Na ◽

In Bok Song ◽

...

Keyword(s):

Defect Density ◽

Substrate Surface ◽

Strongly Correlated ◽

Etching Technique ◽

Force Microscopy ◽

Optical Micrograph ◽

Atomic Force ◽

Influence Of Substrate ◽

Koh Etching ◽

Diamond Paste

Abstract6H-SiC single crystals were grown on various substrates, treated mechanically and chemically in different conditions, by physical vapor transport. To investigate the defect evolution according to the different substrate treatment prior to the growth, the grown crystals were examined by optical micrograph, scanning electron microscopy, atomic force microscopy and molten KOH etching technique. The smoother substrate surface was, the lower defect density the grown SiC had. The highest quality SiC crystal was grown on substrate etched by hydrogen after polished by 0.25 νm diamond paste, having an edge/screw dislocation density of 7.3 ×102 / cm2 without micropipes. Defects, such as dislocations and micropipes, of the grown crystals are found to be strongly correlated with the substrate morphology.

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Reduction in Background Carrier Concentration for 4H-SiC C-face Epitaxial Growth

MRS Advances ◽

10.1557/adv.2016.326 ◽

2016 ◽

Vol 1 (54) ◽

pp. 3631-3636 ◽

Cited By ~ 1

Author(s):

Johji Nishio ◽

Hirokuni Asamizu ◽

Mitsuhiro Kushibe ◽

Hidenori Kitai ◽

Kazutoshi Kojima

Keyword(s):

Epitaxial Growth ◽

Carrier Concentration ◽

Surface Defect ◽

Carrier Lifetime ◽

Epitaxial Film ◽

Defect Density ◽

Growth Parameters ◽

Thickness Variation ◽

Power Devices ◽

Surface Defect Density

ABSTRACT Reduction in background carrier concentration has been investigated for 4H-SiC C-face epitaxial growth in order to be applied for ultra-high voltage power devices. Optimizing epitaxial growth parameters made it possible to achieve 7.6x1013 cm-3 as the background carrier concentration within a whole area of specular 3-inch wafers. In addition to the background carrier concentration reduction, epitaxial film thickness variation, surface defect density and the carrier lifetime have been confirmed to fulfill the requirements for the devices.

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Reducing Surface Defects of CrXOY Film in Mid-Frequency Dual-Magnetron Sputtering

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.291-294.219 ◽

2011 ◽

Vol 291-294 ◽

pp. 219-222

Author(s):

Xiang Yu ◽

Lei Ma ◽

Yang Liu ◽

Zhong Zhou Yang ◽

Hua Meng

Keyword(s):

Magnetron Sputtering ◽

Process Parameters ◽

Surface Defect ◽

Surface Defects ◽

Defect Density ◽

Optimal Parameter ◽

Parameter Combination ◽

Surface Defect Density

Influence of the process parameters of a reactive mid-frequency dual-magnetron sputtering on surface defects of CrxOy film was investigated. The forming mechanisms of the observed droplets and craters were analyzed. The optimal parameter combination for accomplishing fewer surface defects was explored; and the optimized process parameters evidently minimized the surface defects of the film. In the condition of the target current of 16 A, the gases pressure of 0.31 Pa, and the bias voltages in a range of -120~-240 V, an optimized CrxOy film has been synthesized with surface defect density low to 78 defect/mm-2.

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Influence of surface defect density on the ultrafast hot carrier relaxation and transport in $${\hbox {Cu}}_2 {\hbox {O}}$$ photoelectrodes

Scientific Reports ◽

10.1038/s41598-020-67589-z ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Lisa Grad ◽

Zbynek Novotny ◽

Matthias Hengsberger ◽

Jürg Osterwalder

Keyword(s):

Surface Defect ◽

Defect Density ◽

Carrier Relaxation ◽

Hot Carrier ◽

Surface Defect Density

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Reliability of Large-Area Gate Oxide on the C-Face of 4H-SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.615-617.553 ◽

2009 ◽

Vol 615-617 ◽

pp. 553-556

Author(s):

Tetsuo Hatakeyama ◽

Hiroshi Kono ◽

Takuma Suzuki ◽

Junji Senzaki ◽

Kenji Fukuda ◽

...

Keyword(s):

Surface Defect ◽

Defect Density ◽

Gate Oxide ◽

Hydrogen Atmosphere ◽

Scaling Analysis ◽

Strongly Correlated ◽

Large Area ◽

Initial Failure ◽

Random Failures ◽

Surface Defect Density

This paper discusses the issues regarding reliability of large-area (up to 9mm2) gate oxide on the C-face of 4H-SiC. We first show that the initial failure in TDDB characteristics of large area gate oxide is strongly correlated with the surface-defect density. Using wafers with low surface-defect density wafers, scaling analysis of the area-dependence of TDDB characteristics has been performed. It has shown that the reliability of a large area gate oxide is dominated by initial and random failures. Further, we have shown that, by optimizing the temperatures of post-oxidation anneal in hydrogen atmosphere, the random failures of TDDB characteristics are substantially reduced.

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Ex situ and in situ defect density measurements of a-Si:H by means of the cavity ring down absorption technique

MRS Proceedings ◽

10.1557/proc-664-a22.4 ◽

2001 ◽

Vol 664 ◽

Cited By ~ 4

Author(s):

A.H.M. Smets ◽

J.H. van Helden ◽

M.C.M. van de Sanden

Keyword(s):

Surface Defect ◽

Surface Defects ◽

Defect Density ◽

Surface Region ◽

Ex Situ ◽

Density Region ◽

Dual Beam ◽

Surface Defect Density ◽

Absorption Technique ◽

Cavity Ring Down

ABSTRACTFor the first time it is demonstrated that the surface defect density can be measured using the cavity ring down (CRD) absorption technique and it is shown that CRD is more sensitive for surface defects than dual beam photoconductivity (DBP) technique. Ex situ measurements have shown that the surface defects of the oxidized a-Si:H surface are distributed over a surface region with thickness W(d). The obtained surface defect density is 1.0 × 1012 up to 1.4 × 1012 cm-2. During growth the a-Si:H surface defect density region has at least a thickness of 15 nm. During deposition of 15 nm a-Si:H the surface density increases up to a not yet saturated value of 1×1013 cm-2.

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