Journal of the Korean Crystal Growth and Crystal Technology is an official publication of the Korean Association of Crystal Growth (KACG), launched in 1991. The journal publishes 6 issues per year filled with reports of original research and review articles. The peer-reviewed articles contain records of original research that cover diverse theoretical and experimental aspects of crystal growth, crystal technology and related applications. Material categories of interest include but are not limited to: metals, inorganic materials, organic materials, biological materials, semiconductors, polymers, medical/medicinal materials, and newly discovered materials. Theoretical and experimental research and reviews that relate to single- and poly-crystalline materials, powders, liquid crystals and thin films are welcome including those in the following fields; Theory of nucleation, crystallization and growth Modeling and simulation of crystallization and growth Development of growth technique and equipment Characterization of structural and physical properties Other crystal growth-related areas The official title of the journal is “Journal of the Korean Crystal Growth and Crystal Technology (JKCGCT)”. Abbreviated title is “J. Korean Cryst. Growth Cryst. Technol.”. Manuscripts should be submitted to the editorial office by on-line and the submitted manuscripts are peer-reviewed by two reviewers. The manuscript text may be written in Korean or English. The title, abstract, keywords, and references should be written in English. All of the articles published in the JKCGCT are indexed in DOI/Crossref. The citation information and bibliographic information on the JKCGCT is listed in ESCI (Emerging Sources Citation Index) & KCI (Korea Citation Index).
ε-Ga2O3 thin films were grown on 4H-SiC substrates by metal organic chemical vapor deposition (MOCVD) andcrystalline quality were evaluated depend on growth conditions. It was found that the best conditions of the ε-Ga2O3 were grown at a growth temperature of 665°C and an oxygen flow rate of 200 sccm. Two-dimensional growth was completed after the merge of hexagonal nuclei, and the arrangement direction of hexagonal nuclei was closely related to the crystal direction of the substrate.
However, it was confirmed that crystal structure of the ε-Ga2O3 had an orthorhombic rather than hexagonal. Crystal phase transformation was performed by thermal treatment. And a β-Ga2O3 thin film was grown directly on 4H-SiC for the comparison to the phase transformed β-Ga2O3 thin film. The phase transformed β-Ga2O3 film showed better crystal quality than directly grown one.
The optical transmittance of Mn-doped SnO2 monolayer film increased gradually from 80.9 to 85.4 % at 550 nm wavelengths upon increasing the O2/Ar+O2 concentration rate from 0 to 7.9 % and the band gap energy changed from 3.0 to 3.6 eV. The resistivity tended to decrease from 3.21 Ω·cm to 0.03 Ω·cm, reaching a minimum at 2.7 %, and then gradually increased from 0.03 to 52.0 Ω·cm at higher O2/Ar+O2 gas concentration ratio. Based on XPS spectra analysis, the Sn 3d5/2 peak of Mn-doped SnO2 single layer shifted slightly from 486.40 to 486.58 and O1s peak a lso shifted f rom 530.20 to 530.33 eV with increase the O2/Ar+O2 concentration ratio. Therefore, the XPS spectra results indicate that a multiphase with SnO and SnO2 coexisted in the sputtered Mn-doped SnO2 monolayer film.
The fiber composites have been investigated as lightweight structure material platforms for aerospace applications because their strength can be enhanced by adding reinforcement without a significant increase in weight. In this study, thefabrication and characterization of carbon nanotube (CNT) reinforced glass fiber composites are demonstrated to enhance the tensile strength of longitudinal direction along the glass fibers. Due to the reinforcement of CNT in epoxy layers, the yield strength of fiber/epoxy composites is enhanced by about 10 %. Furthermore, using scanning electron microscopy, analysis of fracture surfaces shows that mixed CNT in epoxy layers acts as necking agents between fractured surfaces of fiber/epoxy; thereby, initiation and evolution of crack across fiber composite can be suppressed by CNT necking between fractured surfaces.