The effective synthesis of two-dimensional transition metal dichalcogenides alloy is essential for successful application in electronic and optical devices based on a tunable band gap. Here we show a synthesis process for Mo1−xWxS2 alloy using sulfurization of super-cycle atomic layer deposition Mo1−xWxOy. Various spectroscopic and microscopic results indicate that the synthesized Mo1−xWxS2 alloys have complete mixing of Mo and W atoms and tunable band gap by systematically controlled composition and layer number. Based on this, we synthesize a vertically composition-controlled (VCC) Mo1−xWxS2 multilayer using five continuous super-cycles with different cycle ratios for each super-cycle. Angle-resolved X-ray photoemission spectroscopy, Raman and ultraviolet–visible spectrophotometer results reveal that a VCC Mo1−xWxS2 multilayer has different vertical composition and broadband light absorption with strong interlayer coupling within a VCC Mo1−xWxS2 multilayer. Further, we demonstrate that a VCC Mo1−xWxS2 multilayer photodetector generates three to four times greater photocurrent than MoS2- and WS2-based devices, owing to the broadband light absorption.

DNA-methyltransferase-3B (DNMT3B) plays an important role in the generation of aberrant methylation in carcinogenesis. Polymorphisms and haplotypes of the DNMT3B gene may influence DNMT3B activity on DNA methylation, thereby modulating the susceptibility to lung cancer. To test this hypothesis, we investigated the association of the -283T > C (from exon 1A transcription start site) and -579G > T (from exon 1B transcription start site) polymorphisms in DNMT3B promoter, and their haplotypes with the risk of lung cancer in a Korean population. The DNMT3B genotype was determined in 432 lung cancer patients and 432 healthy controls that were frequency-matched for age and sex. Individuals with at least one -283T allele were at a significantly decreased risk of adenocarcinoma (AC) and small cell carcinoma (SM) [adjusted odds ratio (OR) = 0.48, 95% confidence interval (CI) = 0.28-0.82, P = 0.007; and adjusted OR = 0.47, 95% CI = 0.24-0.93, P = 0.03, respectively] compared with those harboring a -283CC genotype. Individuals with at least one -579G allele were also at a significantly decreased risk of AC and SM (adjusted OR = 0.47, 95% CI = 0.28-0.81, P = 0.006; and adjusted OR = 0.51, 95% CI = 0.26-0.99, P = 0.048, respectively) compared with those having a -579TT genotype. The -283T allele was linked with the -579G allele, and haplotype -283T/-579G was associated with a significantly decreased risk of AC (adjusted OR = 0.48, 95% CI = 0.29-0.81, P = 0.006) as compared with haplotype -283C/-579T. In a promoter assay, carriage of the -283T allele showed a significantly lower promoter activity ( approximately 50%) compared with the -283C allele (P < 0.001), but the -579G > T polymorphism did not have an affect on the DNMT3B promoter activity. These results suggest that the DNMT3B -283T > C polymorphism influences DNMT3B expression, thus contributing to the genetic susceptibility to lung cancer.

Angiogenesis is an essential process in the development, growth, and metastasis of malignant tumors including lung cancer. DNA sequence variations in the vascular endothelial growth factor (VEGF) gene may lead to altered VEGF production and/or activity, thereby causing interindividual differences in the susceptibility to lung cancer via their actions on the pathways of tumor angiogenesis. To test this hypothesis, we investigated the potential association between three VEGF polymorphisms (À À460T > C, +405C > G, and 936C > T)/haplotypes and the risk of lung cancer in a Korean population. VEGF genotypes were determined in 432 lung cancer patients and 432 healthy controls that were frequency matched for age and sex. VEGF haplotypes were predicted using Bayesian algorithm in the phase program. Compared with the combined +405 CC and CG genotype, the +405 GG genotype found associated with a significantly decreased risk of small cell carcinoma [SCC; adjusted odds ratio (OR), 0.36; 95% confidence interval (95% CI), 0.17-0.78]. The 936 CT genotype and the combined 936 CT and TT genotype were also associated with a significantly decreased risk of SCC compared with the 936 CC genotype (adjusted OR, 0.47; 95% CI, 0.26-0.85 and adjusted OR, 0.44; 95% CI, 0.24-0.80, respectively). Haplotype CGT was associated with a significantly decreased risk of SCC (adjusted OR, 0.39; 95% CI, 0.18-0.87), whereas haplotype TCC conferred a significantly increased risk of SCC (adjusted OR, 1.63; 95% CI, 1.14-2.33). None of the VEGF polymorphisms studied significantly influenced the susceptibility to lung cancer except SCC. However, haplotypes TCT and TGT were significantly associated with the risk of overall lung cancer, respectively (adjusted OR, 0.38; 95% CI, 0.25-0.60 and adjusted OR, 3.94; 95% CI, 2.00-7.76, respectively). These effects of haplotypes TCT and TGT on lung cancer risk were observed in three major histologic types of lung cancer. These results suggest that the VEGF gene may be contribute to an inherited predisposition to lung cancer.

The reaction mechanism of area-selective atomic layer deposition (AS-ALD) of AlO thin films using self-assembled monolayers (SAMs) was systematically investigated by theoretical and experimental studies. Trimethylaluminum (TMA) and HO were used as the precursor and oxidant, respectively, with octadecylphosphonic acid (ODPA) as an SAM to block AlO film formation. However, AlO layers began to form on the ODPA SAMs after several cycles, despite reports that CH-terminated SAMs cannot react with TMA. We showed that TMA does not react chemically with the SAM but is physically adsorbed, acting as a nucleation site for AlO film growth. Moreover, the amount of physisorbed TMA was affected by the partial pressure. By controlling it, we developed a new AS-ALD AlO process with high selectivity, which produces films of ∼60 nm thickness over 370 cycles. The successful deposition of AlO thin film patterns using this process is a breakthrough technique in the field of nanotechnology.

Rare earth oxide (REO) atomic layer deposition (ALD) processes are investigated for hydrophobic coatings. Thermal and plasmaenhanced ALD (PE-ALD) Er 2 O 3 and Dy 2 O 3 are developed using the newly synthesized Er and Dy precursors bis-methylcyclopentadienyl-diisopropylacetamidinate-erbium and bis-isopropylcyclopentadienyl-diisopropyl-acetamidinate-dysprosium, with H 2 O and O 2 plasma counter oxidants. The Er and Dy precursors show typical ALD growth characteristics with no nucleation incubation, indicating that they are suitable ALD precursors. The hydrophobicities of ALD-grown Er 2 O 3 and Dy 2 O 3 are investigated, together with those of ALD-grown Y 2 O 3 , La 2 O 3 , and CeO 2 that were previously developed for high-k applications. All the ALD-grown REOs show high hydrophobicity, with water contact angles as high as 90°. After annealing at 500 °C in air for 2 h, hydrophobicity is degraded depending on the kind of material; this degradation is related to the hygroscopy of REOs. In addition, we demonstrate the fabrication of a superhydrophobic surface by depositing highly conformal ALD REO films on 3D Si nanowire nanostructures. The Si NWs are conformally coated with ALD Y 2 O 3 , yielding a surface with a water contact angle of about 158°. The ALD REOs reported herein should find widespread applicability in the fabrication of robust hydrophobic coatings.

This work reports the self-limiting synthesis of an atomically thin, two dimensional transition metal dichalcogenides (2D TMDCs) in the form of MoS2. The layer controllability and large area uniformity essential for electronic and optical device applications is achieved through atomic layer deposition in what is named self-limiting layer synthesis (SLS); a process in which the number of layers is determined by temperature rather than process cycles due to the chemically inactive nature of 2D MoS2. Through spectroscopic and microscopic investigation it is demonstrated that SLS is capable of producing MoS2 with a wafer-scale (~10 cm) layer-number uniformity of more than 90%, which when used as the active layer in a top-gated field-effect transistor, produces an on/off ratio as high as 108. This process is also shown to be applicable to WSe2, with a PN diode fabricated from a MoS2/WSe2 heterostructure exhibiting gate-tunable rectifying characteristics.

Monolithic CAD/CAM lithium disilicate crowns are applicable to posterior implant-supported restorations because the fracture load was higher than the average occlusal force.

We report the effect of YO passivation by atomic layer deposition (ALD) using various oxidants, such as HO, O plasma, and O, on In-Ga-Zn-O thin-film transistors (IGZO TFTs). A large negative shift in the threshold voltage (V) was observed in the case of the TFT subjected to the HO-ALD YO process; this shift was caused by a donor effect of negatively charged chemisorbed HO molecules. In addition, degradation of the IGZO TFT device performance after the O plasma-ALD YO process (field-effect mobility (μ) = 8.7 cm/(V·s), subthreshold swing (SS) = 0.77 V/dec, and V = 3.7 V) was observed, which was attributed to plasma damage on the IGZO surface adversely affecting the stability of the TFT under light illumination. In contrast, the O-ALD YO process led to enhanced device stability under light illumination (ΔV = -1 V after 3 h of illumination) by passivating the subgap defect states in the IGZO surface region. In addition, TFTs with a thicker IGZO film (55 nm, which was the optimum thickness under the current investigation) showed more stable device performance than TFTs with a thinner IGZO film (30 nm) (ΔV = -0.4 V after 3 h of light illumination) by triggering the recombination of holes diffusing from the IGZO surface to the insulator-channel interface. Therefore, we envisioned that the O-ALD YO passivation layer suggested in this paper can improve the photostability of TFTs under light illumination.