• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 1999.05a
• /
• pp.411-414
• /
• 1999

70 ${\AA}$-thick oxides nitridied at various conditions were reoxidized at pemperatures of 900$^{\circ}C$ in dry-O$_2$ ambients for 5～40 mininutes. The gate oxide interface porperties as well as the oxide substrate interface properties of MOS(Metal Oxide Semiconductor) capacitors with various nitridation conditions, reoxidation conditions and pure oxidation condition were investigated. We stuided I$\sub$g/-V$\sub$g/ characteristics, $\Delta$V$\sub$g/ shift under constant current stress from electrical characteristics point of view and breakdown voltage from leakage current point of view of MOS capacitors with SiO$_2$, NO, RNO dielectrics. Overall, our experimental results show that reoxidized nitrided oxides show inproved charge trapping porperites, I$\sub$g/-V$\sub$g/ characteristics and gate $\Delta$V$\sub$g/ shift. It has also been shown that reoxidized nitridied oxide's leakage currented voltage is better than pure oxide's or nitrided oxide's from leakage current(1${\mu}$A) point of view.

• Korean Journal of Materials Research
• /
• v.26 no.10
• /
• pp.556-560
• /
• 2016

Using current-voltage (I-V) and capacitance-voltage (C-V) measurements, the electrical properties of Au and Cu Schottky contacts to n-Ge were comparatively investigated. Lower values of barrier height, ideality factor and series resistance were obtained for the Au contact as compared to the Cu contact. The values of capacitance showed strong dependence on the bias voltage and the frequency. The presence of an inversion layer at the interface might reduce the intercept voltage at the voltage axis, lowering the barrier height for C-V measurements, especially at lower frequencies. In addition, a higher interface state density was observed for the Au contact. The generation of sputter deposition-induced defects might occur more severely for the Au contact; these defects affected both the I-V and C-V characteristics.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.15 no.7
• /
• pp.559-563
• /
• 2002

A threshold voltage model of SiC N-channel MOSFETs for high-temperature and hard radiation environments has been developed and verified by comparing with experimental results. The proposed model includes the difference in the work functions, the surface potential, depletion charges and SiC/$SiO_2$acceptor-like interface state charges as a function of temperature. Simulations of the model shoved that interface slates were the most dominant factor for the threshold voltage decrease as the temperature increase. To verify the model, SiC N-chnnel MOSFETS were fabricated and threshold voltages as a function of temperature were measured and compared wish model simulations. From these comparisons, extracted density of interface slates was $4{\times}10^{12}\textrm{cm}^{-2}eV^{-1}$.

• Proceedings of the KSME Conference
• /
• 2002.08a
• /
• pp.307-310
• /
• 2002

A two-dimensional numerical method for inviscid two-fluid flows with evolution of density interface is developed, and an initially stationary two-dimensional fluid sheet surrounded by another fluid is studied. The Interface between two fluids is modeled as a vertex sheet, and the flow field u÷th the evolution of interface is solved by using vortex-in-cell/front-tracking method. The edge of the sheet Is pulled back into the sheet due to surface tension and a blob is formed at the edge. This blob and fluid sheet are connected by a thin neck. In the inviscid limit, such process of the blob and neck formation is examined in detail and their kinematic characteristics are summarized with dimensionless parameters. The edge recedes at $V=1.06({\sigma}/{\rho}h)^{0.5}$ and the capillary wave Propagating into the fluid sheet must be considered for bettor understanding of the edge receding.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 1999.11a
• /
• pp.303-309
• /
• 1999

Optimum tribological performance of the head/disk system is critical in maintaining reliable data processing in a hard disk drive. Particularly, as the flying height of the slider continues to decrease with increasing recording density, frictional interaction between the slider and the disk need to be better understood. In this work the effect of reduced ambient pressure on the tribological behavior of the head/disk interface is presented. It is found that surface damage of the components can be accelerated by reducing the ambient pressure. This method may be utilized to assess slider/disk compatibility of newly developed systems in short time.

• Proceedings of the KIEE Conference
• /
• 1987.11a
• /
• pp.486-488
• /
• 1987

Studine the characteristic or C.T.I affectine on the tracking failure when interface active materials are diffused into the phenolic resin. we conclude as follow: 1) As the density of $NH_4Cl$ increase the quality or sludge increase the value of C.T.I decreases. 2) The materal of ion absorption can make the period of sludge metallic matal generation delay more than times and the value of C.T.I increase. 3) By addition of interface active material that makes forming period delay, the starting voltage of corona blackdown id delayed and the value of C.T.I is increased.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.19 no.9
• /
• pp.2249-2260
• /
• 1995

An experiment of close contact melting of phase-change medium partially filled in an isothermally heated horizontal cylinder is performed which involves the volume expansion of liquid induced by the solid-liquid density difference. The solid-liquid interface motion and the free surface behavior of liquid were reported photographically. The experimental results show that the curvature of upper solid-liquid interface varied to flat as melting progresses. In addition to the varying interface shape, the melting rate increases with the lower initial height of solid and the free surface height of liquid increases linearly. The experimental results of molten mass fraction were expressed in a function of dimensionless time Fo.Ste$^{3}$4/ and agreed well with the analytical solutions.

• Transactions of the Society of Information Storage Systems
• /
• v.7 no.2
• /
• pp.65-69
• /
• 2011

Head Disk Interface (HDI) in a Hard Disk Drive (HDD) has decreased to achieve high areal density. Thus, the contact between a slider and a disk becomes more important. The contact between the slider and the disk can cause severe wear and damage of both the slider and the disk. Especially, Touch Down (TD) that the contact occurs continuously and repeatedly is extremely dangerous. Therefore, it is necessary to analyze the unstable bouncing vibration of the slider in head-disk interface. In this paper, we investigate the characteristic and causes of the Touch Down.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.35 no.8
• /
• pp.316-322
• /
• 1986

In this paper, the photodoping effect on the interface of Ag-amorphous As2S3 thin film has been investigated by measuring the resistance change of the Ag layer, the absorption coefficient of the As2S3, the optical density of As2S3 layer and the short-circuit photocurrents under light irradiation. As the experimental results, the photodissolution rate and the photodiffusion rate depends on the magnitude of photon energy absorbed in the As2S3. The sensitivity limit of the photodissolution rate at Ag layer was about 630[nm] and the sensitivity limit of the photodiffusion rate at the Ag-As2S3 interface was about 680[nm]. Also, it was found that the depth of photodiffusion was proportional to the square root of exposing time.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.17 no.4
• /
• pp.373-377
• /
• 2004

We have investigated the electrical characterization of metal-oxide-semiconductor (MOS) capacitors formed on the inductively coupled plasma (ICP) etch-damaged both n- and p-type 4H-SiC. We found that there was an effect of a sacrificial oxidation treatment on the etch-damaged surfaces. Current-voltage and capacitance-voltage measurements of these MOS capacitors were used and referenced to those of prepared control samples without etch damage. It has been found that a sacrificial oxidation treatment can improve the electrical characteristics of MOS capacitors on etch-damaged 4H-SiC since the effective interface density and fixed oxide charges of etch-damaged samples have been found to increase while the breakdown field strength of the oxide decreased and the barrier height at the SiC-SiO$_2$ interface decreased for MOS capacitors on etch-damaged surfaces.