• Proceedings of the Korean Vacuum Society Conference
• /
• 2010.08a
• /
• pp.267-267
• /
• 2010

The continuous change in the electronic band structure of metal-adsorbed bilayer graphene was calculated as a function of metal coverage using first-principles calculations. Instead of modifying the unit cell size as a function of metal coverage, the distance between the metal atoms and bilayer graphene in the same $2{\times}2$ unit unit cell was controlled to change the total charges transferred from the metal atoms to bilayer graphene. The validity of the theoretical method was confirmed by reproducing the continuous change in the electronic band structure of K-adsorbed epitaxial bilayer graphene, as shown by Ohta et al. [Science 313, 951 (2006)]. In addition, the changes in the electronic band structures of undoped, n-type, and p-type bilayer graphene were studied schematically as a function of metal coverage using the theoretical method.

• Korean Journal of Materials Research
• /
• v.32 no.1
• /
• pp.51-55
• /
• 2022

Generally, Au electrodes are the preferred top metal electrodes in most perovskite solar cells (PSCs) because of their appropriate work function for hole transportation and their resistance to metal-halide formation. However, for the commercialization of PSCs, the development of alternative metal electrodes for Au is essential to decrease their fabrication cost. Ag electrodes are considered one of the most suitable alternatives for Au electrodes because they are relatively cheaper and can provide the necessary stability for oxidation. However, Ag electrodes require an aging-induced recovery process and react with halides from perovskite layers. Herein, we propose a bilayer Au/Ag electrode to overcome the limitations of single Au and Ag metal electrodes. The performance of PSCs based on bilayer electrodes is comparable to that of PSCs with Au electrodes. Furthermore, by using the bilayer electrode, we can eliminate the aging process, normally an essential process for Ag electrodes. This study not only demonstrates an effective method to substitute for expensive Au electrodes but also provides a possibility to overcome the limitations of Ag electrodes.

• Journal of Technologic Dentistry
• /
• v.39 no.2
• /
• pp.101-107
• /
• 2017

Purpose: The purpose of this study was to compare the shear bond strength of the metal-heat pressed glass ceramic bilayer structure. Methods: Metal framework specimens were prepared and surface is spreaded opaque(IPS InLine system opaque, IvoclarVivadent, Liechtenstein). There were 10 specimens for each bilayer dental ceramic group. The first group was porcelain fused metal, Press on metal IPS Inline press group, and press on metal HASS prototype group. Specimens measured for the shear bond strength on Schwickerath test by Instron universal testing machine(Instron3345, Instron Corp., USA). Mean average bond strength values of each specimen group were analyzed using a one-way ANOVA analysis of variance Saphiro-wilk's test. Statistical analysis were performed using IBM SPSS 23.0(IBM Co., Armonk, USA) Results: $RMS{\pm}SD$ The highest mean average HASS POM showed a bond strength value ($47.55{\pm}12.80Mpa$). The lowest mean average values Porcelain fused metal ($33.30{\pm}2.00Mpa$). Independent t-test was conduct to analysis the significant difference (p<0.05) (Table 3). Conclusion: Three kinds of Metal/ glass bilayer dental ceramics bond strength were clinical acceptability. Especially, as lithium disilicate containing represents higher bond strength.

• Journal of the Korean Ceramic Society
• /
• v.36 no.6
• /
• pp.604-610
• /
• 1999

Silicide layer structures and morphology degradation of the surface and interface of the silicide layers for he Co/refractory metal bilayer sputter-deposited on the P-doped polycrystalline Si substrate and subjected to rapid thermal annealing were investigated and compared with those on the single Si substrate. The CoSi-CoSi2 phase transition temperature is lower an morphology degradation of the silcide layer occurs more severely for the Co/refractorymetal bilayer on the P-doped polycrystalline Si substrate than on the single Si substrate. Also the final layer structure and the morphology of the films after silicidation annealing was found to depend strongly upon the interlayer metal. The layer structure after silicidation annealing of Co/Hf/doped-poly Si is Co-Hf alloy/polycrystalline CoSi2/poly Si substrate while that of Co/Nb is polycrystalline CoSi2/NbSi2/polycrystalline CoSi2/poly Si.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2005.05a
• /
• pp.60-60
• /
• 2005

• Proceedings of the Materials Research Society of Korea Conference
• /
• 1992.05b
• /
• pp.152-153
• /
• 1992

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2005.05a
• /
• pp.235-235
• /
• 2005

• 한국정보디스플레이학회:학술대회논문집
• /
• 2009.10a
• /
• pp.571-574
• /
• 2009

Metal oxide/metal bilayer structures are explored as contacts with a low injection barrier in organic thin-film transistors (OTFTs) in an effort to realize their true potential for low-cost electronics. OTFTs with a bilayer electrode of $WO_3$ (10nm) and Al shows a saturation mobility as large as 0.97 $cm^2$/Vsec which are comparable to those of Au-based control samples (~0.90 $cm^2$/Vsec). Scaling of contact resistance with respect to the thickness of $WO_3$ layer is also discussed.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2016.02a
• /
• pp.302.1-302.1
• /
• 2016

Solution-processed amorphous metal-oxide thin-film transistors (TFTs) are considered as promising candidates for the upcoming transparent and flexible electronics due to their transparent property, good performance uniformity and possibility to fabricate at a low-temperature. In addition, solution processing metal oxide TFTs may allow non-vacuum fabrication of flexible electronic which can be more utilizable for easy and low-cost fabrication. Recently, for high-mobility oxide TFTs, multi-layered oxide channel devices have been introduced such as superlattice channel structure and heterojunction structure. However, only a few studies have been mentioned on the bias illumination stress in the multi- layered oxide TFTs. Therefore, in this research, we investigated the effects of bias illumination stress in solution-processed bilayer oxide TFTs which are fabricated by the deep ultraviolet photochemical activation process. For studying the electrical and stability characteristics, we implemented positive bias stress (PBS) and negative bias illumination stress (NBIS). Also, we studied the electrical properties such as field-effect mobility, threshold voltage ($V_T$) and subthreshold slop (SS) to understand effects of the bilayer channel structure.

• Bulletin of the Korean Chemical Society
• /
• v.18 no.2
• /
• pp.190-193
• /
• 1997

In search of new amphiphiles that form coordinatively polymerized bilayer membranes (CPBMs) in water, N-dodecyl-3-[2-hydroxy-3-(4-carboxymethyl-2-thiazolylazo)-5-methylphenyl]propanamide (5) was prepared. The bilayer membranes of 5 prepared in the presence of 2 equivalents of NaOH were further sonicated in the presence of transition metal ions such as Ni(Ⅱ), Cu(Ⅱ), Co(Ⅱ), or Co(Ⅲ) at > 80 ℃ to obtain CPBMs. The CPBMs of 5 were characterized by transmission electron microscopy, gel filtration, resistivity against disruption in aqueous ethanol, visible spectra, and release of entrapped 5(6)-carboxyfluorescein. Remarkable stabilization of the bilayer membranes through coordinative polymerization was evidenced by the resistivity of the Ni(Ⅱ)-CPBM of 5 against disruption in 40%(v/v) ethanol upon incubation for 20 hr.