MOS 소자의 移動性 陽이온들의 電氣的 特性

金末文,南尙熙 嶺南大學校附設 基礎科學硏究所 1985 基礎科學硏究 Vol.5 No.-

Thermally stimulated Ionic Current (TSIC) measurements have been used to study the kinetic behavior of mobil ions in Al-SiO₂-Si Structures formed by evaporation of Al electrodes onto thermally oxidized Si wafer. It is shown that three distinct peaks were observed in the temperature range 30~350℃. The first peak at about 100℃, and the second peak at about 200℃, and the third peak at about 350℃. The first peak is to the motion of ??, wheras the second peak results from the motion of ??, the third peak is to the motion of ??. It is shown that the ionic current is limited primarily by release of mobil ions from traps at the interface. This model is proposed which accurately predict the detrapping rate for an arbitary temperature-time profile and change of voltage. Its parameters are the initial distribution of ions among the trapping states, ??, and heating rate β, characterizing the attempt-to-escape frequency, and that trapped mobil ions release from trap. Activation energy, E canbe derived from analysis of a TSCI curve. Activatron energy is to the results of 0.52 for ??, and 0.81 for ??. The results is shallow trap for ??, and deep trap for ??. A value for β can be determined by performing experiment in the TSIC stages. Increase of peak current was caused by the increase of β. Changes of capacitance-voltage(C-V) characterics by Bias-Temperature(B-T) stresses have been measured for detecting mobil ions.

Ionizing 방사선이 MOS 소자에 미치는 영향에 관한 연구

김말문,한병국,배인호,김인수,유승권 嶺南大學校 基礎科學硏究所 1990 基礎科學硏究 Vol.10 No.-

The analysis of a simple model for radiation-induced space charge buildup in the SiO₂layers of MOS(Metal-Oxide-Semiconductor) is carried out. The model assumes that hole­electron pairs are created in SiO₂layer by the radition and that some of the electrons thus created drift out of SiO₂layer under action of an applied potential across the oxide, V??while corresponding holes become trapped. in these experiments, MOS capacitors having 1100Å and 1950Å SiO₂thickness are exposed to X-ray. Both p-and n-type substrate and Al metal electrodes are used to evaluate characteristics of radiation induced positive charges. From the results of these experiments △V ?? and the number of holes trapped in SiO₂layer strongly depend on oxide thickness, electric field across the oxide layer and absorbed dose. Alwayys C-V(Capacitance-Volage) curve shifts negatively without any relation to substrate types and applied voltage during radiation. This means that trapped charges in the oxide are always positive.

SiO₂층 속의 이동성 이온의 이동도 측정

金末文,韓炳國 嶺南大學校附設 基礎科學硏究所 1989 基礎科學硏究 Vol.9 No.-

Na?? and K+ ions have been contaminated in thermally grown SiO₂thin film of metal-oxide-silicon structure. The mobilities of the Na+ and K+ ions were determined from the isothermal transient ionic current method measured in temperature ranges 100∼250℃ and 300∼450℃ respectively. For Na ions; μ=3.3x10-⁴exp(-0.49ev/KT)∼7.6x10-³exp(-0.55eV/KT)㎠/V.sec and for K+ ions; μ=4.4x10-³exp(1.03eV/KT)∼4.6x10-³exp(-1.04eV/KT)㎠/V.sec.

이온 주입된 실리콘에서 라만 특성 연구

김말문,이동건,문영희,한병국 嶺南大學校 基礎科學硏究所 1994 基礎科學硏究 Vol.14 No.-

Raman characterization measurements are performed in order to study the effects of the furnace annealing and rapid thermal annealing on arsenic implanted silicon wafers. The post-implanted period was followed by thermal isochronal annealing at various temperatures. Special attention has been given to the amorphous/crystal transition occurring at various annealing temperatures. The changes of the dimensions of the microcrystalline regions and the root mean square bond angle deviation of Si-Si bonds in amorphized regions are evaluated.

非晶質 SiC를 절연막으로 한 MIS 構造의 電氣的 特性

金末文,李進熙 嶺南大學校附設 基礎科學硏究所 1984 基礎科學硏究 Vol.4 No.-

The current-voltage characteristics in glow dscharge deposited amorphous SiC thin film on single crystal Si substrate exhibit space-charge limited current in the presence of exponentially distributed traps. Trap parameters are deduced from current-voltage data. Capacitance-voltage curve of A1-SiC-Si structure exhibit flat-band voltage shift 4.2V from ideal capacitance-voltage curve, and resulting fixed space charge densisity and interface state charge density are obtained, ??, ??, respectively.

MOS 구조에서 S₁O₂층의 Charge Trappiog

金末文,金在峯,南尙熙 嶺南大學校附設 基礎科學硏究所 1987 基礎科學硏究 Vol.7 No.-

In the process of avalanche injection of electrons into silicon dioxide, beside eloctron trapping in the bulk of the oxide, there are slow and fast inferface states generated. The slow state are donors and positive charged when empty. Togother with positive charge in the interface states, they compensated the negative bulk charge to give the turn-around effect. The final C-V carve is due to a complex sum of different charge components. As a function of avalanche fluence ?? , the flatband voltage shift did not increase monotonically. Instead, after a maximum voltage shift was reached, the flatband voltage decrease with further injection of electrons. The turn around effect is observed after ?? are injected into an oxide. The effect was explained by the generation of interface states.

MBE(molecular beam epitaxy)로 성장된 GaAs/AlAs 초격자의 특성연구

김동렬,김말문 嶺南大學校 基礎科學硏究所 1996 基礎科學硏究 Vol.16 No.-

GaAs/AlAs superlattice was grown by molecular beam epitaxy with a thickness of 15 monolayers. We have performed photoluminescence measurement. Measurement were performed as a function of excitation laser power and temperature. The photoluminescence peak intensity as a function of excitation laser power is well described by a straight line on logarithmic plot, indicating that radiative recombination mechanism is excitonic-like transition. Finally, we have showed the temperature dependence of the peak energy of the HI-Cl transition. When lattice temperature was decreased, the peak energy first increased, following the temperature dependence of the bulk GaAs band gap, and deviated to the lower energy side by about 4 meV at 7.2K from extrapolated curve. The observed Stokes shift is in good agreement with previous results on multiple-quantum well sample of the high quality.

Double Crystal Diffractometer를 이용한 이온주입된 실리콘의 로킹커브 분석

문영희,김말문 嶺南大學校 基礎科學硏究所 1995 基礎科學硏究 Vol.15 No.-

Double Crystal Diffractometer (DCD) was used to measure the defects due to As ion implanted silicon wafer. (100)-oriented Si wafers were implanted with 60 keV As ions at 1 X ?? ?? dose. Simulations based on the dynamical theory of diffraction were compared with the measured X-ray rocking curves. The results obtained by x-ray rocking curve analysis showed a defect layer at the original amorphous/crystalline interface of 1400Å depth. In addition arsenic ion concentration profiles and defect distributions in depth were obtained by SIMS and TRIM-code simulation.

Cds-SiO₂-Si의 電氣的 特性

南尙熙,金末文 嶺南大學校附設 基礎科學硏究所 1981 基礎科學硏究 Vol.1 No.-

Introducting a passivating layer of SiO₂at the CdS-Si junction is found to improve the I-V characteristics of the heterodiodes. Studies indicate that the reverse-bias characteristics of these structures are determined primarily by the filling and unfilling of interface states at the Si-SiO₂ interface. This is substantiated by the temperature dependence of these characteristics. Reverse-bias C-V characteristics show abrupt junction like behavior, also controlled by the interface-state charge. Under forward-bias, tuneling through the oxide is responsible for conduction.

Si/SiO₂구조의 적외선 분광 연구

金仁洙,金末文,裵仁鎬 嶺南大學校 基礎科學硏究所 1990 基礎科學硏究 Vol.10 No.-

In this paper, we have investigated, using infrared spectroscopy, structural and compositional characteristics of a various thin films grown on silicon wafers from O₂gas at 800℃. From IR transmission spectra, we observed that peak positions and features were changed in the spectra of films with increasing oxide layer. The spectra revealed a clear thickness dependent structural transformation in thermal SiO₂. The Lambert-Bouguer's law for thin films has been confirmed, and the absorption coeffecient calculated for n-and p-type were 6.14×10⁴cm-¹ and 7.68×10⁴cm-¹, respectively.