• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.317-319
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• 1997

We have studied the properties of $GaAs_{1-x}P_x$ epitaxial films on the GaP using VPE method by CVD. The surface carrier concentration and PL power increased with increasing the epitaxial temperature while PL wave length decreased. The Power out of the LED with $GaAs_{1-x}P_x$/GaP structure decreased with increasing the epitaxial temperature while the forward voltage of the LED increased. Specially, The LED of $GaAs_{1-x}P_x$/GaP structure represents good electrical and optical properties when the $GaAs_{1-x}P_x$ layer was epitaxially grown at $810^{\circ}C$.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.121.2-121.2
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• 2014

Synthesis of catecholamine from aniline is achieved by plasma enhanced CVD process. Catecholamine has a variety of functions in body such as brain and bloodstream controls. Catecholamine also has an interesting property of a material independent ability of functionalizing surface, which is found at mussels' adhesive nature. Synthesis of catecholamine has only been available from DOPA by chemical reduction and oxidation. This study presents the direct synthesis of catecholamine from further elemental source, aniline, which has not been achieved by a conventional chemical method. The process also indicates that a variety of catecholamine can be formed by controlling reactant gases. In additional to PECVD's very useful properties such as conformal, ultrathin and uniform coatings, a direct synthesis from aniline and a capability of controlling formation of a variety catecholamine is believed to open up a numerous applications.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.2020-2022
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• 2002

SiC direct bonding technology is very attractive for both SiCOI(SiC-on-insulator) electric devices and SiC-MEMS fileds because of its application possibility in harsh environements. This paper presents on pre-bonding according to HF pre-treatment conditions in SiC wafer direct bonding using PECVD oxide. The PECVD oxide was characterized by XPS and AFM, respectively. The characteristics of bonded sample were measured under different bonding conditions of HF concentration and applied pressure, respectively. The bonding strength was evaluated by tensile strength method. Components existed in the interlayer were analyzed by using FT-IR. The bond strength depends on the HF pre-treatment condition before pre-bonding (Min : 5.3 kgf/$cm^2{\sim}$ Max : 15.5 kgf/$cm^2$).

• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.180-182
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• 1990

Today, according to the temperature lowering of VLSI technology which have been required, the new thin film technology of low temperature have appeared. Plasma CVD method, one of low temperature technologies, have major problems with many interface trap defects. In this paper, we prepared ammonia free SiN film containing small H that acts as a defect impurity, and investigated the electrical properties of Laser assisted deposition film.

• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.191-194
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• 1990

A $SnO_2$: F/$SiO_2$ duble layer on the sodalime glass is described for developing a low-cost substrate of a-Si solar cells. Dipping and Pyrosol method, have been used for thin film deposition, and electrical and optical properties have been analysed. Finally, p-i-n a-Si solar cells have been fabricated on this substrate by plasma CVD and their average efficiency is 4% approximately.

• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.187-190
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• 1990

A new technique is described for developing low-cost $SnO_2$ : F thin films as TCO (Transparent Conducting Oxide) substrate of a-Si solar cells. A novel Pyrosol equipment has been developed, and $SnO_2$ : F thin films have been deposited under the condition of varing dopant concentration, temperature and composition rate of solution. Futhermore, electrical and optical properties of thin films have been measured, and exhibit resistivity of $4.3{\times}10^{-4}{\Omega}$ cm and transmittance of 80% which is almost at the same level as those of $SnO_2$ : F thin films by CVD.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.574-574
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• 2012

We report a simple way of fabricating high-quality carbon nanoscrolls (CNSs) by taking advantage of strain relief due to large difference in strain at the interface of graphene and underlying layer. This method allows strain-controlled self rolling-up of monolayer graphene during etching process at predefined positions on SiO2/Si substrates by photolithography. The size and the length of the CNSs can be easily controlled by adjusting the thickness of the underlying layer and by pre-patterning. Raman spectroscopy studies show that the CNSs is free of significant defects, and the electronic structure and phonon dispersion are slightly different from those of two-dimensional graphene. The preparation of high-quality CNSs may open up new opportunities for both fundamental and applied research of CNSs.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.114-114
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• 2011

Graphene is the hottest topic in condensed-matter physics due to its unusual electronic structures such as Dirac cones and massless linear dispersions. Graphene can be epitaxially grown on various metal surfaces with chemical vapor deposition (CVD) processes. Such epitaxial graphene shows modified electronic structures caused by substrates. In the method for removal of the effect of substrate, there are bi, tri-layer graphene, gold intercalation, and oxygen intercalation. Here, We will present the changes of geometric and electronic structure of graphene grown on Ru(0001) by oxygen intercalation between graphene and Ru(0001). Using Scanning tunneling microscopy (STM) and spectroscopy (STS), we observed the aspect that the band gap features near the fermi level of graphene on Ru(0001) system is shifted and narrow. Based on the observed results, two effects by intercalated oxygen were considered.

• Journal of the Korean Graphic Arts Communication Society
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• v.29 no.3
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• pp.133-142
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• 2011

We produce a photosensitive convex plate to research a Nickel metal relief printing plate using galvanic process. A Method for preparing DLC convex plate that is metalized on Nickel metal relief printing plate using CVD(Chemical Vapor Deposition) process and $N_2DLC$-convex plate that is DLC metalized thin film layer of $N_2$ plasma surface treatment are comprised. DLC thin film layers on Nickel surface are fragile. The results of the research indicate that the coefficient of friction on DLC metalized thin film layer is relatively low than Nickel surface and the durability of Nickel surface coated DLC metalized thin film layer is superior to Nickel surface. A relative evaluation of three form plate wetting properties using varnish liquid-drop plate indicates superior printing aptitudes for $N_2DLC$, DLC, Nichel plate order as above.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.98-99
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• 2014

질산산화법(nitric acid oxidation method)은 저온에서 안정적인 산화막을 형성하는 직접산화공정으로 azeotropic point(68 wt%)인 120도 이하의 온도에서 산화막을 형성한다. 120도에서 형성한 질산산화막은 CVD법으로 형성한 산화막 보다 낮은 누설전류밀도(leakage current density)를 나타낸다. 또한 질산의 농도가 증가함에 따라 형성한 산화막의 누설전류밀도가 감소하며, 이는 열산화법으로 형성한 산화막 보다 낮다. 질산산화의 낮은 누설전류밀도는 형성한 산화막의 높은 원자 밀도와 낮은 계면준위밀도에 의한 것으로 이 특성을 이용하여 게이트 절연막(gate insulator)과 태양전지의 passivation막으로 응용되고 있다.