• 한국표면공학회지
• /
• 제50권5호
• /
• pp.345-351
• /
• 2017

A double-layered anti-reflective coating with hydrophilic/abrasion-resistant properties was studied using anatase titanium dioxide($TiO_2$) and silicon oxycarbide($SiO_xC_y$) thin film. $TiO_2$ and $SiO_xC_y$ thin films were sequentially deposited on a glass substrate by DC sputtering and PECVD, respectively. The optical properties were measured by UV-Vis-NIR spectrophotometer. The abrasion-resistance and the hydrophilicity were observed by a taber abrasion tester and a contact angle analyzer, respectively. The $TiO_2/SiO_xC_y$ double-layer thin film had an average transmittance of 91.3%, which was improved by 10% in the visible light region (400 to 800 nm) than that of the $TiO_2$ single-layer thin film. The contact angle of $TiO_2/SiO_xC_y$ film was $6.9^{\circ}$ right after UV exposure. After 9 days from the exposure, the contact angle was $10.2^{\circ}$, which was $33^{\circ}$ lower than that of the $TiO_2$ single-layer film. By the abrasion test, $SiO_xC_y$ film showed a superior abrasion-resistance to the $TiO_2$ film. Consequently, the $TiO_2/SiO_xC_y$ double-layer film has achieved superior anti-reflection, hydrophilicity, and abrasion resistance over the $TiO_2$ or $SiO_xC_y$ single-layer film.

• 전자공학회논문지
• /
• 제50권7호
• /
• pp.115-121
• /
• 2013

본 연구에서는 TiInZnO(TiIZO)를 채널층으로 하는 thin film transistors(TFTs)를 제작하였다. TiIZO 층은 InZnO(IZO)와 Ti target을 이용하여 RF-magnetron co-sputtering system 방식으로 상온에서 증착하였으며, 어떠한 열처리도 하지 않았다. Ti의 첨가가 어떠한 영항을 주는지 연구하기 위해 X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS) 분석을 시행하였으며, 전기적인 특성을 측정하였다. Ti의 첨가는 Ti target의 rf power 변화에 따라 달리하였다. Ti의 첨가가 전류점멸비에 큰 영향을 주는 것을 확인하였고, 이것은 Ti의 산화력이 In과 Zn보다 뛰어나 산소결함자리의 형성을 억제하기 때문이다. Ti의 rf power가 40W일 때 가장 좋은 특성을 나타냈으며, 전류점멸비, 전자이동도, 문턱전압, subthreshold swing이 각각 $10^5$, 2.09 [$cm^2/V{\cdot}s$]. 2.2 [V], 0.492 [V/dec.]로 측정되었다.

• 한국결정성장학회지
• /
• 제10권3호
• /
• pp.271-277
• /
• 2000

투광성 $TiO_2$박막을 다량의 물을 사용한 티타늄알콕사이드 수용계로부터 sol-gel법으로 제조하였다. sol의 제조를 위해 각각 1 mole의 titanium(IV)iso-propoxide, acetylacetone과 8 mole의 isopropyl-alcohol로부터 킬레이트 화합물을 만들었다. 그리고 sol의 안정성을 위한 0.02~0.50 mole의 HCI과 코팅 접착성을 위한 0.3 mole의 polyethylene glycol을 함유한 50 mole의 수용액을 엄밀히 제어하여 킬레이트 화합물에 적하하였다. 제조된 sol로부터 dipping, 건조 및 $400^{\circ}C$에서 열처리하여 $TiO_2$박막을 제조하였으며, XRD, SEM, UV-visible spectrometer 등을 이용하여 특성을 검토하였다. TTIP : AcAc : IPA : $H_2$O : PEG : HCl의 몰비가 1 : 1 : 8 : 50 : 0.3 : 0.15인 조성을 갖는 중성 sol은 30일까지도 안정한 상태를 유지하였고 코팅성이 양호하였다. 30회까지 반복 침지하고 건조 및 열처리한 anatase상 $TiO_2$박막은 평활한 표면과 두께 약 2 $\mu\textrm{m}$의 치밀한 미세구조를 보였다. 제조한 $TiO_2$박막은 가시광선 영역에서 약 80%의 투과도를 나타내었다.

• 대한의용생체공학회:의공학회지
• /
• 제21권3호
• /
• pp.273-277
• /
• 2000

순 티타늄(공업용 순 티타늄, 2급)의 0.5M에서 0.7M 농도의 $H_3PO_4$ 용액에서 $0.3\~l.0 A/dm^2$의 정전류 밀도변화에 따른 anodizing 거동을 관찰하였다. 이때 형성된 산화피막을 SEM과 XRD로 관찰, 분석하였다. 실험결과 0.05M $H_3PO_4$ 용액의 조건에서 전압-시간 (V-T)곡선의 초기에는 직선적인 관계를 보였고, 전류밀도가 증가함에 따라 포물선의 형태를 나타내었다. 그리고 V-T곡선의 형태는 전해질의 농도의 증가에 따라 큰 변화가 없었지만, 최종적인 전압은 감소하였다. 티타늄의 산화피막은 전해질 농도와 전류밀도가 증가할수록 미세한 입자 형태에서 눈꽃과 같고 층을 이룬 입자들로 구성된 구조를 나타내었다. 산화막과 전해질의 계면에서의 방전에 의해 산화피막의 국소적인 침착과 용해를 동반하였다. 산화피막의 결정성은 anodizing 전압이 증가할수록 증가하였고 전해질의 농도가 증가할수록 감소하는 경향을 보였다.

• 한국기계가공학회지
• /
• 제13권1호
• /
• pp.121-128
• /
• 2014

Superfinishing is essential for mirror surfaces, because among mechanical components cylindrical workpieces such as spindles must maintain precision and reliability with respect to functional characteristics. However, research on standardization of polishing film application combination to obtain mirror surfaces is insufficient. Consequently, this has been a factor in rising costs of mechanical components. Therefore, in this study, experiments have been conducted to determine efficient polishing film application combination for mirror surfaces ranging from ductile materials such as SM45C, brass, aluminium 7075, and titanium to brittle materials such as $Al_20_3$, SiC, $Si_3N_4$, and $ZrO_2$. From the experimental results, efficient polishing film application combination for metallic materials and ceramic materials is confirmed.

• 한국표면공학회지
• /
• 제29권6호
• /
• pp.788-796
• /
• 1996

$TiO_2$ films prepared by RF magnetron sputtering, electron beam evaporation, ion assisted deposition (IAD) and sol-gel method are prepared on c-Si substrate and vitreous silica substrate respectively. From the transmission spectra of $TiO_2$ films on vitreous silica substrate in the spectral region from 190 nm to 900 nm, k($\lambda$) of $TiO_2$ is obtained. Using k($\lambda$) in the interband transition region the coefficients of the quantum mechanical dispersion relation of an amorphous $TiO_2$ and hence n($\lambda$) including the optically opaque region of above fundamental transition energy are obtained. The spectroscopic ellipsometry spectra of $TiO_2$ films in the spectral region of 1.5-5.0eV are model analyzed to get the film packing density variation versus i) substrate material, ii) film thickness and iii) film growth technique. The complex refractive index change of these $TiO_2$ films versus water condensation is also studied. Film micro-structures by SE modelling results are compared with those by atomic force microscopy images and X-ray diffraction data.

• 한국전기전자재료학회논문지
• /
• 제30권8호
• /
• pp.514-519
• /
• 2017

TiN (titanium nitride) films were prepared using the RF magnetron sputtering technique. The films were deposited by pure $N_2$ plasma sputtering. Their mechanical properties, such as nano-indentation hardness, friction coefficient, and surface wettability, have been investigated. X-ray diffraction (XRD) studies revealed that the orientation of $TiN_X$ films changed towards the (111) orientation with decreasing working pressure due to a strong compressive stress during deposition. The strongest TiN (111) orientation was found when the film was deposited at a working pressure of 1 Pa. This film showed the largest hardness (16 GPa) and smallest friction coefficient (0.17) among the studied samples. Moreover, this film was found to be accompanied by a water-repellent surface with water contact angle more than $100^{\circ}$.

• 센서학회지
• /
• 제14권2호
• /
• pp.131-135
• /
• 2005

This paper describes the ohmic contact formation of single crystalline 3C-SiC thin films heteroepitaxially grown on Si(001) wafers. In this work, a TiW (Titanium-tungsten) film as a contact matieral was deposited by RF magnetron sputter and annealed with the vacuum and RTA (rapid thermal anneal) process respectively. Contact resistivities between the TiW film and the n-type 3C-SiC substrate were measured by the C-TLM (circular transmission line model) method. The contact phases and interface the TiW/3C-SiC were evaulated with XRD (X-ray diffraction), SEM (scanning electron microscope) and AES (Auger electron spectroscopy) depth-profiles, respectively. The TiW film annealed at $1000^{\circ}C$ for 45 sec with the RTA play am important role in formation of ohmic contact with the 3C-SiC substrate and the contact resistance is less than $4.62{\times}10^{-4}{\Omega}{\cdot}cm^{2}$. Moreover, the inter-diffusion at TiW/3C-SiC interface was not generated during before and after annealing, and kept stable state. Therefore, the ohmic contact formation technology of single crystalline 3C-SiC using the TiW film is very suitable for high temperature MEMS applications.

• 한국표면공학회지
• /
• 제32권3호
• /
• pp.307-311
• /
• 1999

The well-crystalline hydroxyapatite($Ca_{10}(PO_4)_6(OH)_2$ ; HAp) layer having a biocompatibility was successfully coated onto titanium substrate using a radio-frequency magnetron sputtering, and effects of sputtering gas and the thickness of HAp film on a crystal growth of the HAp layers were investigated. The deposition rate of the layer sputtered with water-vapour gas was slower than that of the layer sputtered with argon gas. The results of X-ray diffraction demonstrated that the about $0.8\mu\textrm{m}$ thick HAp film under water-vapour gas was an amorphous phase, the about $1.2\mu\textrm{m}$ thick film was (100) plane-oriented HAp, and the about $1.5\mu\textrm{m}$ thick film was (001)plane-oriented HAp. FT-IR analysis proved that hydroxyl group of the layer sputtered with argon gas was defected, but that of the layer sputtered with water-vapour gas was not defected. From these results, it was favorable to use water-vapour gas on the HAp coatings onto metal surface.

• Bulletin of the Korean Chemical Society
• /
• 제23권1호
• /
• pp.140-142
• /
• 2002