• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
• /
• pp.120-121
• /
• 2006

To investigate the ZnO thin films which are interested in the next generation of short wavelength LEDs and Lasers, the ZnO thin films were deposited by RF magnetron sputtering system. Al sputtering process of ZnO thin films substrate temperature, work pressure respectively is $100^{\circ}C$ and 15 mTorr, and the purity of target is ZnO 5N. The ZnO thin films were in-situ annealed at $600^{\circ}C$, $800^{\circ}C$ in $O_2$ atmosphere. Phosphorus (P) and arsenic (As) were diffused into ZnO thin films sputtered by RF magnetron sputtering system in ampoule tube which was below $5{\times}10^{-7}$ Torr. The dopant sources of phosphorus and arsenic were $Zn_3P_2$ and $ZnAS_2$. Those diffusion was perform at $650^{\circ}C$ during 3hr. We confirmed that p-type properties of ZnO thin films were concerned with dopant sources rather than diffusion temperature.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 디스플레이 광소자분야
• /
• pp.140-142
• /
• 2003

ZnO thin films are demanded for device applications, so ZnO buffer layer was used to improve for good properties of ZnO thin film. In this study, the structural, electrical and optical properties of ZnO thin films deposited with various buffer thickness was investigated by X-ray diffraction (XRD), Hall measurements, Photoluminescence(PL). ZnO buffer layer and ZnO thin films on sapphire($Al_{2}O_{3}$) substrate have been deposited $200^{\circ}C$ and $400^{\circ}C$ respectively by pulsed laser deposition. It is observed the variety of lattice constant of ZnO thin film by (101) peak position shift with various buffer thickness. It is founded that ZnO thin film with buffer thickness of 20 nm was larger resistivity of 200 factor and UV/visible of 2.5 factor than that of ZnO thin films without buffer layer. ZnO thin films with buffer thickness of 20 nm have shown the most properties.

• 한국전기전자재료학회논문지
• /
• 제18권11호
• /
• pp.1043-1047
• /
• 2005

To investigate the electrical properties of the ZnO films which are interested in the next generation of short wavelength LEDs and Lasers, our ZnO thin films were deposited by RF sputtering system. At sputtering process of ZnO thin films, substrate temperature, work pressure respectively is $300^{\circ}C$ and 5.2 mTorr, and the purity of target is ZnO 5N. The thickness of ZnO thin films was about $2.1\;{\mu}m$ at SEM analysis after sputtering process. Phosphorus (P) and arsenic (As) were diffused into the undoped ZnO thin films sputtered by RF magnetron sputtering system in ampoule tube which was below $5\times10^{-7}$ Torr. The dopant sources of phosphorus and arsenic were $Zn_3P_2$ and $ZnAs_2$. Those diffusion was perform at 500, 600, and $700^{\circ}C$ during 3 hr. We found the diffusion condition of the conductive ZnO films which had n- and p-type properties. Our ZnO thin film has not only very high carrier concentration of above $10^{17}/cm^3$ but also low resistivity of below $2.0\times10^{-2}\;{\Omega}cm$.

• 대한전자공학회논문지SD
• /
• 제45권7호
• /
• pp.32-36
• /
• 2008

본 연구에서는 펄스 레이저 법으로 200 mTorr 의 산소 분압에서 기판 온도를 $200^{\circ}C$ 에서 $600^{\circ}C$ 까지 변화시켜 가며, quartz 기판 위에 $In_2O_3-ZnO$ 박막을 제작하여 광학적 및 전기적 특성을 조사하였다. XRD 측정을 통해 $In_2O_3-ZnO$ 박막이 다결정 상태인 것을 알 수 있었으며, 기판 온도가 $500^{\circ}C$로 증가함에 따라 $35.5^{\circ}$ 부근의 $In_2O_3$ (400) 피크는 감소한 반면 $30.6^{\circ}$ 부근의 $In_2O_3$ (222) 피크는 증가했다. 박막의 표면을 AFM 으로 조사한 결과, round type 의 결정립들이 관찰되었으며 표면 거칠기 값은 $500^{\circ}C$에서 제작한 박막에서 가장 낮은 값 (6.15 nm) 을 나타내었다. 모든 $In_2O_3-ZnO$ 박막이 가시광 영역에서 평균 82% 이상의 투과율을 보였다. 또, $500^{\circ}C$에서 제작한 $In_2O_3-ZnO$ 박막에서 가장 높은 캐리어 농도 ($2.46{\times}10^{20}cm^{-3}$) 값과 가장 낮은 비저항 ($1.36{\times}10^{-3}{\Omega}cm$) 값을 나타내었다.

• Transactions on Electrical and Electronic Materials
• /
• 제4권6호
• /
• pp.13-16
• /
• 2003

Mn-doped $ZnGa_{2}O_{4}$:$Mn^{2+}$ (M=S, Se) thin film phosphors have been grown using a pulsed laser deposition technique under various growth conditions. The structural characterization carr~ed out on a series of $ZnGa_{2}O_{4}$:$Mn^{2+}$ (M=S, Se) films grown on MgO(l00) substrates usmg Zn-rich ceramic targets. Oxygen pressure was varied from 50 to 200 mTorr and Zn/Ga ratio was the function of oxygen pressure. XRD patterns showed that the lattice constants of the $ZnGa_{2}O_{4}$:$Mn^{2+}$ (M=S, Se) thin film decrease with the substitution of sulfur and selenium for the oxygen in the $ZnGa_2O_4$. Measurements of photoluminescence (PL) properties of $ZnGa_{2}O_{4}$:$Mn^{2+}$ (M=S, Se) thin films have indicated that MgO(100) is one of the most promised substrates for the growth of high quality $ZnGa_2O_{4-x}M_{x}$:$Mn^{2+}$ (M=S, Se) thin films. In particular, the incorporation of Sulfur or Selenium into $ZnGa_2O_4$ lattice could induce a remarkable increase in the intensity of PL. The increasing of green emission intensity was observed with $ZnGa_2O_{3.925}Se_{0.075}:$Mn^{2+}$ and $ZnGa_2O_{3.925}S_{0.05}$:$Mn^{2+}$ films, whose brightness was increased by a factor of 3.1 and 1.4 in comparison with that of $ZnGa_{2}O_{4}$:$Mn^{2+}$ films, respectively. These phosphors may promise for application to the flat panel displays.

• Advances in nano research
• /
• 제1권2호
• /
• pp.93-103
• /
• 2013

An ultrasonic-mediated assisted stepwise method has been developed for depositing transparent ZnO films from aqueous solution. Rinsing in low ethylene glycol temperature was easy to produce intermediate phase of $Zn(OH)_2$, rinsing in $120^{\circ}C$ ethylene glycol was observed the diffraction peak of intermediate $Zn(OH)_2$ in early report, the rinsing temperature plays an important role in the process of $Zn(OH)_2$ phase transformed to ZnO, high rinsing temperature actually improved the intermediate phase. However, the effect of rinsing on the intermediate phase is yet to be understood clearly. The effect of different rinsing procedures, involving either of or a combination of successive ionic layer adsorption and reaction (SILAR) and ultrasonic-assisted rinsing, prior to hydrolysis in ethylene glycol was found to improve the occurrence $Zn(OH)_2$ in ZnO thin films. In the zinc complex ($[Zn(NH_3)_4]^{2+}$) solution, excess ($[Zn(NH_3)_4]^{2+}$) absorbed in glass substrate transformed incompletely to ZnO and exist as $Zn(OH)_2$ phase in thin films. In films deposited at low temperature, rinsing procedure is applied to improve excess $Zn(OH)_2$ and obtain smoother transparent thin films.

• The Korean Journal of Ceramics
• /
• 제7권2호
• /
• pp.85-92
• /
• 2001

Thin films of ZnO and Al doped ZnO were prepared by rf magnetron sputter techniques. When the oxygen fraction in Ar-O$_2$ sputter gas was about 2.0%, the films exhibited the composition of Zn:O=1.05:1. The films prepared at 250 W contain larger grains than the films grown at 100 W. However, high deposition rate seems to deteriorates the crystallinity as well as Al-substitution, resulting in lower concentration of mobile electrons. The Al-doped ZnO films which were deposited at $500^{\circ}C$ show resistance of 1$\times$10$^-2$ Wcm; optical band gap of the films ranges from 3.25 to 3.40 eV. These electrical and optical features are related with microstructural as well as crystalline characteristics of the films.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
• /
• pp.145-146
• /
• 2006

The most Important research topic in the development of ZnO LED and LD is the production of p-type ZnO thin film that has minimal stress with outstanding stoichiometric ratio. In this study, Phosphorus diffused into the undoped ZnO thin films using the ampoule-tube method for the production of p-type znO thin films. The undoped ZnO thin films were deposited by RF magnetron sputtering system on $GaAs_{0.6}P_{0.4}$/GaP and Si wafers. 4N Phosphorus (P) was diffused into the undoped ZnO thin films in ampoule-tube which was performed and $630^{\circ}C$ during 3hr. We found the diffusion condition of the conductive ZnO films which had p-type properties with the highest mobility of above 532 $cm^2$/Vs compared with other studies PL spectra measured at 10K for the purpose of analyzing optical properties of p-type ZnO thin film showed strong PL intensity in the UV emission band around 365nm ~ 415nm and 365nm ~ 385nm.

• 한국세라믹학회지
• /
• 제33권2호
• /
• pp.149-154
• /
• 1996

ZnO and Al-doped ZnO thin films were prepared by sol-gel dip-coating method and electrical and optical properties of films were investigated. Using the zinc acetate dihydrate and acetylaceton(AcAc) as a chelating agent stable ZnO sol was synthesized with HCl catalyst. Adding aluminium chloride to the ZnO sol Al-doped ZnO sol could be also synthesized. As Al contents increase the crystallinity of ZnO thin film was retarded by increased compressive stress in the film resulted from the difference of ionic radius between Zn2+ and Al3+ The thickness of ZnO and Al-doped ZnO thin film was in the range of 2100~2350$\AA$. The resistivity of ZnO thin films was measured by Van der Pauw method. ZnO and Al-doped ZnO thin films with annealing temperature and Al content had the resistivity of 0.78~1.65$\Omega$cm and ZnO and Al-doped ZnO thin film post-annealed at 40$0^{\circ}C$ in vacuum(5$\times$10-5 torr) showed the resistivity of 2.28$\times$10-2$\Omega$cm. And the trans-mittance of ZnO and Al-doped ZnO thin film is in the range of 91-97% in visible range.

• 한국결정학회지
• /
• 제2권2호
• /
• pp.1-6
• /
• 1991

RF 마그네트론 스퍼터링법을 이용하여 ZnO 박 막을 실리콘 기판과 Corning 7059유리 기판위에 증착시켜 증착변수에 따른 ZnO 박막의 구조적, 전기적, 광학적 특성을 분석하였다. 1 전력을 증가시킴에 따라 c축 배향성이 뛰어난 ZnO 박막을 얻을 수 있었으며, 2가 34.4인 피크의 X·ray rocking curve표준 편차 값은 6.8-7.2˚사이에 있었다. 유리 기판위에 증착된 ZnO 박막은 가시광선 영역에서 실험조건에 관계없이 80% 이상의 높은 투광도를 갖고 있었다. ZnO박막의 비저항 값은 증착 변수인 rf전력과 Ar압력에 의해 심한 영향을 받고 있었으며 3×102-2×109 Ω·cm의 비저항 영역을 갖고 있었다.