• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.128.2-128.2
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• 2014

Long-wave infrared detectors using the type-II InAs/GaSb strained superlattice (T2SL) material system with the nBn structure were designed and fabricated. The band gap energy of the T2SL material was calculated as a function of the thickness of the InAs and GaSb layers by the Kronig-Penney model. Growth of the barrier material (Al0.2Ga0.8Sb) incorporated Te doping to reduce the dark current. The full width at half maximum (FWHM) of the 1st satellite superlattice peak from the X-ray diffraction was around 45 arc sec. The cutoff wavelength of the fabricated device was ${\sim}10.2{\mu}m$ (0.12eV) at 80 K while under an applied bias of -1.4V. The measured activation energy of the device was ~0.128 eV. The dark current density was shown to be $1.2{\times}10^{-5}A/cm^2$ at 80 K and with a bias -1.4 V. The responsivity was 1.9 A/W at $7.5{\mu}m$ at 80K and with a bias of -1.9V.

• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.187-190
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• 1987

This paper is for the charge storage effect and C-V characteristics of MIS type diode which is the basic structural unit of charge-coupled device after growing the $Pb_{1-x}Sn_xTe$ crystal. $Pb_{1-x}Sn_xTe$ singlecrystal dbtained from the horizental furnace using Bridgman method. To judge whether the grown singlecrystal is suitable for specimen or not, it was investigated by X-ray diffraction analysis, thermogravimetry and differential thermal analysis. The C-V characteristics of the specimen caused to anodic oxidation was the best when the insulator film's depth was 250[$\AA$]. Measuring the C-V characteristics aftermanufacturing MIS type diode resulted that the whole capacitance was the largest when the supply voltage was low, 0.3[V] and the capacitance also varied according to the variance frequence when the supply voltage is over 0.5[V]. From the above result, even if the supply voltage is low, the $Pb_{1-x}Sn_xTe$ also have a good charge storage effect.

• Journal of Information Display
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• v.12 no.1
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• pp.1-4
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• 2011

A complementary inverter was fabricated using pentacene and N-N -dioctyl-3,4,9,10-perylene tetracarboxylic diimide-C (PTCDI-C8) for p- and n-type transistors on a poly(ether sulfone) substrate, respectively. The mobilities of the p- and n-type transistors were 0.056 and 0.013 $cm^2$/Vs, respectively. The inverter, which was composed of p- and n-type transistors, showed a gain of 48.6 when $V_{DD}$ = -40V and at the maximum noise margin of $V_{DD}$/2. A ring oscillator was also fabricated by cascading five inverters. The five-stage ring oscillator showed the maximum output frequency of 10 kHz when $V_{DD}$ = -170 V.

• Journal of the Korean Mathematical Society
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• v.59 no.4
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• pp.757-774
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• 2022

Let a and b be positive even integers. An even [a, b]-factor of a graph G is a spanning subgraph H such that for every vertex v ∈ V (G), d_H(v) is even and a ≤ dH(v) ≤ b. Let κ(G) be the minimum size of a vertex set S such that G - S is disconnected or one vertex, and let σ₂(G) = min_uv∉E(G) (d(u)+d(v)). In 2005, Matsuda proved an Ore-type condition for an n-vertex graph satisfying certain properties to guarantee the existence of an even [2, b]-factor. In this paper, we prove that for an even positive integer b with b ≥ 6, if G is an n-vertex graph such that n ≥ b + 5, κ(G) ≥ 4, and σ₂(G) ≥ ${\frac{8n}{b+4}}$, then G contains an even [4, b]-factor; each condition on n, κ(G), and σ₂(G) is sharp.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.5
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• pp.664-674
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• 2016

The electrical properties of Ti/p-type InP Schottky diodes with and without polyaniline (PANI) interlayer was investigated using current-voltage (I-V) and capacitance-voltage (C-V) measurements. The barrier height of Ti/p-type InP Schottky diode with PANI interlayer was higher than that of the conventional Ti/p-type InP Schottky diode, implying that the organic interlayer influenced the space-charge region of the Ti/p-type InP Schottky junction. At higher voltages, the current transport was dominated by the trap free space-charge-limited current and trap-filled space-charge-limited current in Ti/p-type InP Schottky diode without and with PANI interlayer, respectively. The domination of trap filled space-charge-limited current in Ti/p-type InP Schottky diode with PANI interlayer could be associated with the traps originated from structural defects prevailing in organic PANI interlayer.

• Transactions of the Korean hydrogen and new energy society
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• v.8 no.2
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• pp.79-90
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• 1997

Extensive work has been done on investigating the inner cell pressure characteristics of sealed type Ni-MH battery in which Zr-Ti-Mn-V-Ni alloy is used as anode. The inner cell pressure of this type Ni-MH battery much more increases with the charge/discharge cycling than that of the other type Ni-MH battery where commercialized $AB_5$ type alloy is used as anode. The increase of inner cell pressure in the sealed type Ni/MH battery using Zr-Ti-Mn-V-Ni alloy system is mainly due to the accumulation of oxygen gas during charge/discharge cycling. The accumulation of oxygen gas arises mainly due to the low rate of oxygen recombination on the MH electrode surface during charge/discharge cycling. The difference of oxygen recombination rate between $AB_5$ type electrode and Zr-Ti-Mn-V-Ni electrode is caused by the difference of electrode reaction surface area resulting from different particle size after their activation and the difference of surface catalytic activity for oxygen recombination reaction, respectively. After EIS analysis, it is identified that the surface catalytic activity affects much more dominantly on the oxygen recombination reaction than the reaction surface area does. In order to suppress the inner cell pressure of Ni-MH battery where Zr-Ti-Mn-V-Ni is used as anode, it is suggested that the surface catalytic activity for oxygen recombination should be improved.

• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.53-54
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• 2006

Arsenic doped p-type ZnO thin films have been realized on intrinsic (100) GaAs substrate by RF magnetron sputtering and thermal annealing treatment. p-Type ZnO exhibits the hole concentration of $9.684{\times}10^{19}cm^3$, resistivity of $2.54{\times}10^{-3}{\Omega}cm$, and mobility of $25.37\;cm^2/Vs$. Photoluminescence (PL) spectra of As doped p-type ZnO thin films reveal neutral acceptor bound exciton ($A^{0}X$) of 3.3437 eV and a transition between free electrons and acceptor levels (FA) of 3.2924 eV. Calculated acceptor binding energy ($E_A$) is about 0.1455 eV. Thermal activation and doping mechanism of this film have been suggested by using X-ray photoelectron spectroscopy (XPS). p-Type formation mechanism of As doped ZnO thin film is more related to the complex model, namely, $As_{Zn}-2V_{Zn}$, in which the As substitutes on the Zn site, rather than simple model, Aso, in which the As substitutes on the O site. ZnO-based p-n junction was fabricated by the deposition of an undoped n-type ZnO layer on an As doped p-type ZnO layer.

• Journal of the Korean Institute of Telematics and Electronics
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• v.15 no.6
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• pp.39-42
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• 1978

Orthorhombic yellow PbO thin films were prepared by evaporating PbO powder in vacuum and annealed in air. The evaporation was carried out by Hashing method. The energy gap, the type of electric conduction and the grain size of these films were 2.63eV, f type, and 670 nm respectively.

• Journal of applied mathematics & informatics
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• v.26 no.5_6
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• pp.991-1010
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• 2008

A discrete minmax fractional subset programming problem is considered. Various parametric and parameter-free global sufficient optimality conditions and duality results are discussed under generalized ($F,{\alpha},{\rho},{\theta}$)-V-type-I n-set functions.

• East Asian mathematical journal
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• v.38 no.1
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• pp.13-20
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• 2022

We establish multiplicity results for positive solutions to the Schrödinger-type singular positone problem: -∆u + V (x)u = λf(u) in Ω, u = 0 on ∂Ω, where Ω is a bounded domain in ℝ^N, N > 2, λ is a positive parameter, V ∈ L^∞(Ω) and f : [0, ∞) → (0, ∞) is a continuous function. In particular, when f is sublinear at infinity we discuss the existence of at least three positive solutions for a certain range of λ. The proofs are mainly based on the sub- and supersolution method.