• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.431-431
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• 2008

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.397-397
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• 2008

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.12
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• pp.1865-1869
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• 1990

N-Channel polysilicon MOSFETs (W/L=20/1.5, 3, 5.10\ulcorner) were fabricated using RTP (Rapid Thermal Processor) and hydrogen passivation. The N+ source, drain and gate were annealed and recrystallized using RTP at temperature of 1000\ulcorner-1100\ulcorner. But the active areas were not specially crystallized before growing the gate oxide. Without the hydrogen passivarion, excellent transistor characteristics (ON/OFF=5.10**6, S=85MV/DEC, IL=51pA/\ulcorner) were obtained for 1.5\ulcorner MOSFET. Also the transistor characteristics were improved by hydrogen passivation.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.155-156
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• 2000

We propose a new in-situ fluorine passivation of poly-Si TFTs by excimer laser annealing to reduce the trap density and improve the reliability significantly. This improvement is due to the formation of stronger Si-F bonds than Si-H bonds which passivate the trap states.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.430-430
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• 2012

The surface recombination velocity of the silicon solar cell could be reduced by passivation with insulating layers such as $SiO_2$, SiNx, $Al_2O_3$, a-Si. Especially, the aluminium oxide has advantages over other materials at rear surface, because negative fixed charge via Al vacancy has an additional back surface field effect (BSF). It can increase the lifetime of the hole carrier in p-type silicon. The aluminium oxide thin film layer is usually deposited by atomic layer deposition (ALD) technique, which is expensive and has low deposition rate. In this study, ICP-assisted reactive magnetron sputtering technique was adopted to overcome drawbacks of ALD technique. In addition, it has been known that by annealing aluminium oxide layer in nitrogen atmosphere, the negative fixed charge effect could be further improved. By using ICP-assisted reactive magnetron sputtering technique, oxygen to nitrogen ratio could be precisely controlled. Fabricated aluminium oxy-nitride (AlON) layer on silicon wafers were analyzed by x-ray photoelectron spectroscopy (XPS) to investigate the atomic concentration ratio and chemical states. The electrical properties of Al/($Al_2O_3$ or $SiO_2/Al_2O_3$)/Si (MIS) devices were characterized by the C-V measurement technique using HP 4284A. The detailed characteristics of the AlON passivation layer will be shown and discussed.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.237.1-237.1
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• 2016

Electrical properties of graphene-based field effect transistors (G-FETs) can be degraded in ambient conditions owing to physisorbed oxygen or water molecules on the graphene surface. Passivation technique is one of a fascinating strategy for fabrication of G-FETs, which allows to sustain electrical properties of graphene in the long term without disrupting its inherent properties: transparency, flexibility and thinness. Ironically, despite its importance in producing high performance graphene devices, this method has been much less studied compared to patterning or device fabrication processes. Here we report a novel surface passivation method by using atomically thin self-assembled alkane layers such as C18- NH2, C18-Br and C36 to prevent unintentional doping effects that can suppress the degradation of electrical properties. In each passivated device, we observe a shift in charge neutral point to near zero gate voltage and it maintains the device performance for 1 year. In addition, the fabricated PG-FETs on a plastic substrate with ion-gel gate dielectrics exhibit not only mechanical flexibility but also long-term stability in ambient conditions. Therefore, we believe that these highly transparent and ultra-thin passivation layers can become a promising candidate in a wide range of graphene based electronic applications.

• Journal of the Korean institute of surface engineering
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• v.50 no.3
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• pp.219-224
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• 2017

The K gettering in $SiO_2/PSG/SiO_2/Al-1%Si$ multilevel thin films was investigated using SIMS(secondary ion mass spectrometry) and XPS(X-ray Photoelectron Spectroscopy) analysis. DC magnetron sputter techniques and APCVD(atmosphere pressure chemical vapor deposition) were utilized for the deposition of Al-1%Si thin films and $SiO_2/PSG/SiO_2$ passivations, respectively. Heat treatment was carried out at $400^{\circ}C$ for 5 h in air. SIMS depth profiling was used to determine the distribution of K, Al, Si, P and other elements throughout the $SiO_2/PSG/SiO_2/Al-1%Si$ multilevel thin films. XPS was used to analyze binding energies of Si and P elements in PSG passivation layers. K peaks were observed throughout the $PSG/SiO_2$ passivation layers on the Al-1%Si thin films and especially at the $PSG/SiO_2$ interfaces. K gettering in $SiO_2/PSG/SiO_2/Al-1%Si$ multilevel thin films is considered to be caused by a segregation type of gettering. The chemical state of Si and P elements in PSG passivation appears to be $SiO_2$ and $P_2O_5$, respectively

• Current Photovoltaic Research
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• v.7 no.4
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• pp.125-129
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• 2019

Recently, carrier-selective contact solar cells have attracted much interests because of its high efficiency with low recombination current density. In this study, we investigated the effect of phosphorus doped amorphous silicon layer's characteristics on the passivation properties of tunnel oxide passivated carrier-selective contact solar cells. We fabricated symmetric structure sample with poly-Si/SiOx/c-Si by deposition of phosphorus doped amorphous silicon layer on the silicon oxide with subsequent annealing and hydrogenation process. We varied deposition temperature, deposition thickness, and annealing conditions, and blistering, lifetime and passivation quality was evaluated. The result showed that blistering can be controlled by deposition temperature, and passivation quality can be improved by controlling annealing conditions. Finally, we achieved blistering-free electron carrier-selective contact with 730mV of i-Voc, and cell-like structure consisted of front boron emitter and rear passivated contact showed 682mV i-Voc.

• Journal of the Korean Vacuum Society
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• v.10 no.1
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• pp.27-30
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• 2001

Electromigration Phenomena in Al-1%Si thin film interconnections under DC and PDC conditions were investigated. Thin film interconnections with $SiO_2$ and PSG/$SiO_2$ dielectric passivation layer were formed by a standard photolithography process method and test line lengths were 100, 400, 800, 1200, and 1600 $\mu\textrm{m}$. The current density of $1.19\times10^7\textrm{A/cm}^2$ was stressed in Al-1%Si thin film interconnections under DC condition. The current density of $1.19\times10^7\textrm{A/cm}^2$ was also applied under PDC condition at the frequency of 1 Hz with the duty factor of 0.5. The electromigration resistance of PSG/SiO2 dielectric passivation test line was stronger than $SiO_2$ dielectric passivation test line. The lifetime under PDC was 2-4 times longer than DC condition. As the thin film interconnection line increased, the lifetime decreased and saturated over the critical length. Failure patterns by an electromigration were dominated by void-induced electrical open and hillock-induced electrical short.

• Korean Journal of Materials Research
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• v.21 no.5
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• pp.288-294
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• 2011

Simultaneous Ni and C codeposition by electrolysis was investigated with the aim of obtaining better corrosion resistivity and surface conductivity of a metallic bipolar plate for application in fuel cells and redox flow batteries. The carbon content in the Ni-C composite plate fell in a range of 9.2~26.2 at.% as the amount of carbon in the Ni Watt bath and the roughness of the composite were increased. The Ni-C composite with more than 21.6 at.% C content did not show uniformly dispersed carbon. It also displayed micro-sized defects such as cracks and crevices, which result in pitting or crevice corrosion. The corrosion resistance of the Ni-C composite in sulfuric acid is similar with that of pure Ni. Electrochemical test results such as passivation were not satisfactory; however, the Ni-C composite still displayed less than $10^{-4}$ $A/cm^2$ passivation current density. Passivation by an anodizing technique could yield better corrosion resistance in the Ni-C composite, approaching that of pure Ni plating. Surface resistivity of pure Ni after passivation was increased by about 8% compared to pure Ni. On the other hand, the surface resistivity of the Ni-C composite with 13 at.% C content was increased by only 1%. It can be confirmed that the metal plate electrodeposited Ni-C composite can be applied as a bipolar plate for fuel cells and redox flow batteries.