• 한국세라믹학회지
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• 제35권6호
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• pp.619-625
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• 1998

Mn doped {{{{ {Zn {Ga }_{2 }O }_{4 } }} thin film phosphors were prepared on Si(100) wafers and ITO coated glass substrates by rf magnetron sputtering technique and the effects of the substrates dopant and the sputtering paramet-ers were analyzed, Changes of the oreintation were observed after annealine tratment. The grain size of {{{{ {Zn {Ga }_{2 }O }_{4 } }} : Mn thin film deposited on Si wafer was smaller than that on ITO/glass substrate which resulted in higher PL intensity. The PL spectra of Mn doped {{{{ {Zn {Ga }_{2 }O }_{4 } }} thin films showed sharp green luminescence spec-trum. According to CL spectrum it could be concluded that Mn ions acted as an actuator for green emission by substituting Zn atom sites.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.409-409
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• 2011

All solid-state thin film lithium batteries have many applications in miniaturized devices because of lightweight, long-life, low self-discharge and high energy density. The research of cathode materials for thin film lithium batteries that provide high energy density at fast discharge rates is important to meet the demands for high-power applications. Among cathode materials, lithium manganese oxide materials as spinel-based compounds have been reported to possess specific advantages of high electrochemical potential, high abundant, low cost, and low toxicity. However, the lithium manganese oxide has problem of capacity fade which caused by dissolution of Mn ions during intercalation reaction and phase instability. For this problem, many studies on effect of various transition metals have been reported. In the preliminary study, the Sn-substituted LiMn2O4 thin films prepared by pulsed laser deposition have shown the improvement in discharge capacity and cycleability. In this study, the thin films of LiMn2O4 and LiSn0.0125Mn1.975O4 prepared by RF magnetron sputtering were studied with effect of deposition parameters on the phase, surface morphology and electrochemical property. And, all solid-state thin film batteries comprised of a lithium anode, lithium phosphorus oxy-nitride (LiPON) solid electrolyte and LiMn2O4-based cathode were fabricated, and the electrochemical property was investigated.

• 한국재료학회지
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• 제16권6호
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• pp.394-399
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• 2006

Ferroelectric $HoMnO_3$ thin films were deposited on the Si(100) substrate at $700^{\circ}C$ for 2 hrs by metalorganic chemical vapor deposition (MOCVD) and post-annealed at 850oC by rapid thermal process (RTP). Electrical properties and crystalline phases of $HoMnO_3$ thin films were investigated as a function of postannealing time. Single phase of hexagonal symmetry with c-axis preferred orientation was obtained from $HoMnO_3$ thin films post-annealed at $850^{\circ}C$ for 5 min, while the c-axis preferred orientation was decreased with the increase of post-annealing time, and the thin films post-annealed at $850^{\circ}C$ for 15 min showed the mixture phases of hexagonal and orthorhombic symmetry. P-E (Polarization-Electric field) hysteresis loop of ferroelectric $HoMnO_3$ thin films was observed only for the single phase of hexagonal symmetry, but that was not observed for the mixture phases of the hexagonal and orthorhombic symmetry, which was discussed with the bond valence of Mn ion of crystalline phase. Leakage current density was dependent on the microstructure of thin films as well as the change of valence of Mn ion.

• 한국세라믹학회지
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• 제40권7호
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• pp.652-656
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• 2003

녹색발광을 하는 스피넬 구조의 ZnGa$_2$O$_4$:Mn 형광체박막을 산소분압비를 증착변수로 이용하여 rf 마그네트론 스퍼터링법으로 증착하였으며, 증착된 박막을 산화, 진공+질소 분위기에서 각각 열처리를 하였다. 증착시 산소분압비 및 열처리시 산소분위기가 형광체 박막의 성장 및 발광특성에 미치는 영향을 관찰하였다. 열처리시 박막의 산화를 막을수록 발광특성이 향상되는 것으로 나타났다.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2000년도 춘계연구발표회 논문개요집
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• pp.128-129
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• 2000

• 한국자기학회지
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• 제15권5호
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• pp.265-269
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• 2005

강자성 공명 측정을 통하여 다양한 층 구성을 갖는 교환 바이어스 박막들의 교환 결합 특성에 대해 연구하였다. 공명자기장의 각도의존 실험을 통하여 일축방향이방성 자기장과 일축이방성 자기장을 구하여 분석하였다. NiFe 단일 박막과 비교하여 교환 바이어스된 NiFe/IrMn, IrMn/NiFe/IrMn, NiFe/IrMn/CoFe 박막들은 큰 일축방향이방성 자기장을 나타내었으며, 일축이방성 자기장 또한 큰 값을 나타내었다. 그러나 NiFe/Cu/IrMn의 경우, Cu의 두께가 두꺼울 때는 매우 작은 일축방향이방성 자기장을 나타내었으며, NiFe 단일 박막과 비슷한 크기의 일축이방성 자기장을 나타내었다. NiFe/IrMn/CoFe 박막의 경우 NiFe와 CoFe 강자성층들에 의해 두 개의 공명 자기장이 나타났다. 그 외에 공명 자기장의 선폭에 관한 분석이 교환 바이어스 특성과 연관하여 논의되어졌다.

• 전자공학회논문지A
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• 제31A권9호
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• pp.89-95
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• 1994

BaTiO$_{x}$ thin film as insulator and ZnS:Mn film as phosphour layer for thin film electrouminescent device have been deposited by thermal evalporation and dependence of electrical and opeical characeristics have been studied. The optimum deposition conditions for the BaTiO$_{x}$ thin film are such that BaTiO$_{3}$/TiO$_{2}$ mixing ratio was 0.7, sub strate temperature was 100 $^{\circ}C$ and annealing time was 1 hour at 300 $^{\circ}C$. In this case, the dielectric constant of BaTiO$_{x}$ thin film fabricated under those optimum conditions was 26, and for AnS:Mn thin films, the crystallization was done well and the deposition rate was 1300 $\AA$/min when substrate temperature was 200$^{\circ}C$. Thin film Electroluminescent devices were fabricated using BaTiO$_{x}$ and AnS:Mn thin films. The luminescence threshold voltage of device was 41.5 V and brightness was 1.2${\mu}W/cm^{2}$ at appied voltage of 50 V.

• Journal of Electrical Engineering and Technology
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• 제2권4호
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• pp.525-531
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• 2007

Ni(75 wt.%)-Cr(20 wt.%)-Al(3 wt.%)-Mn(4 wt.%)-Si(1 wt.%) alloy thin films were prepared using the DC magnetron sputtering process by varying the sputtering conditions such as power, pressure, substrate temperature, and post-deposition annealing temperature in order to fabricate a precision thin film resistor. For all the thin film resistors, sheet resistance, temperature coefficient of resistance (TCR), and crystallinity were analyzed and the effects of sputtering conditions on their properties were also investigated. The oxygen content and TCR of Ni-Cr-Al-Mn-Si resistors were decreased by increasing the sputtering pressure. Their sheet resistance, TCR, and crystallinity were enhanced by elevating the substrate temperature. In addition, the annealing of the resistor thin films in air at a temperature higher than $300^{\circ}C$ lead to a remarkable rise in their sheet resistance and TCR. This may be attributed to the improved formation of NiO layer on the surface of the resistor thin film at an elevated temperature.

• 한국재료학회지
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• 제22권8호
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• pp.385-389
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• 2012

Significant improvements in the switching voltage distribution are required for the development of unipolar resistive memory devices using $MnO_x$ thin films. The $V_{set}$ of the as-grown $MnO_x$ film ranged from 1 to 6.2 V, whereas the $V_{set}$ of the oxygen-annealed film ranged from 2.3 to 3 V. An excess of oxygen in an $MnO_x$ film leads to an increase in $Mn^{4+}$ content at the $MnO_x$ film surface with a subsequent change in the $Mn^{4+}/Mn^{3+}$ ratio at the surface. This was attributed to the change in $Mn^{4+}/Mn^{3+}$ ratios at the $MnO_x$ surface and to grain growth. Oxygen annealing is a possible solution for improving the switching voltage distribution of $MnO_x$ thin films. In addition, crystalline $MnO_x$ can help stabilize the $V_{set}$ and $V_{reset}$ distribution in memory switching in a Ti/$MnO_x$/Pt structure. The improved uniformity was attributed not only to the change of the crystallinity but also to the redox reaction at the interface between Ti and $MnO_x$.

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