• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.460-463
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• 2000

The current-voltage characteristics of the sandwich system at different annealing temperatures and different bias voltages have been studied. In order to prepare the Al/V$O_X$/Al sandwich devices structure, thin films of vanadium oxide(V$O_X$) was deposited by r.f. magnetron sputtering from $V_2$$O_5$ target in 10% gas mixture of argon and oxygen, and annealed during lhour at different temperatures in vacuum. Crystall structure, surface morphology, and thickness of films were characterized through XRD, SEM and I-V characteristics were measured by electrometer. The films prepared below 20$0^{\circ}C$ were amorphous, and those prepared above 300 $^{\circ}C$were polycrystalline. At low fields electron injected to conduction band of vanadium oxide and formed space charge, current was limited by trap. Conduction mechanism at mid fields due to Schottky emission, while at high fields it changed to Fowler-Nordheim tunneling effects.

• Transactions on Electrical and Electronic Materials
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• 제16권3호
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• pp.151-155
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• 2015

We fabricated the Cu Schottky contact on an n-type Ge wafer and investigated the forward bias current-voltage (I-V) characteristics in the temperature range of 100~300 K. The zero bias barrier height and ideality factor were determined based on the thermionic emission (TE) model. The barrier height increased and the ideality factor decreased with increasing temperature. Such temperature dependence of the barrier height and the ideality factor was associated with spatially inhomogeneous Schottky barriers. A notable deviation from the theoretical Richardson constant (140.0 Acm^-2K^-2 for n-Ge) on the conventional Richardson plot was alleviated by using the modified Richardson plot, which yielded the Richardson constant of 392.5 Acm^-2K^-2. Finally, we applied the theory of space-charge-limitedcurrent (SCLC) transport to the high forward bias region to find the density of localized defect states (N_t), which was determined to be 1.46 × 10¹² eV^-1cm^-3.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 광주전남지부
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• pp.87-90
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• 2006

Two SiC radiation detector samples were irradiated by Co-60 gamma rays. The irradiation was performed with dose rates of 5 kGy/hour and 15 kGy/hour for 8 hours, respectively. Metal/semiconductor contacts on the surface were fabricated by using a thermal evaporator in a high vacuum condition. The SiC detectors have metal contacts of Au(2000 ${\AA}$)/Ni(300 ${\AA}$) at Si-face and of Au(2000 ${\AA}$)/Ti(300 ${\AA}$) at C-face. I-V characteristics of the SiC semiconductor were measured by using the Keithley 4200-SCS parameter analyzer with voltage sources included. From the I-V curve, we analyzed the Schottky barrier heights(SBHs) on the basis of the thermionic emission theory. As a result, the 6H-SiC semiconductor showed- similar Schottky barrier heights independent to the dose rates of the irradiation with Co-60 gamma rays.

• 반도체디스플레이기술학회지
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• 제5권1호
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• pp.21-25
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• 2006

To improve the performance of organic thin film transistor, we investigated the properties of gate insulator's surface according to the leakage current by I-V measurement. The surface was treated by the dilute n-octadecyltrichlorosilane solution. The alkyl group of n-octadecyltrichlorosilane induced the electron tunneling and the electron tunneling current caused the breakdown at high electric field, consequently shifting the breakdown voltage. The 0.5% sample with an electron-rich group was found to have a large leakage current and a low barrier height because of the effect of an energy barrier lowered by, thermionic current, which is called the Schottky contact. The surface properties of the insulator were analyzed by I-V measurement using the effect of Poole-Frankel emission.

• Journal of Information Display
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• 제10권4호
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• pp.143-148
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• 2009

The theoretical current density equations for organic semiconductors was derived according to the internal carrier emission equation based on the diffusion model at the Schottky barrier contact and the mobility equation based on the field dependence model, the so-called "Poole-Frenkel mobility model." The electric field becomes constant because of the absence of a space charge effect in the case of a higher injection barrier height and a lower sample thickness, but there is distribution in the electric field because of the space charge effect in the case of a lower injection barrier height and a higher sample thickness. The transition between the injection- and bulk-limited currents was presented according to the Schottky barrier height and the sample thickness change.

• 한국재료학회지
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• 제5권8호
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• pp.1020-1025
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• 1995

Au/Si(100) Schotty diode를 l00k~300k 온도범위에서 current voltage(I-V), capacitance-voltage(C-V)측정을 하였다. 얻어진 Schottky barrier height(SBH)갑은 실온에서 두측정값 모두 (0.79$\pm$0.02)eV 이다. 그러나 온도가 감소할수록 I-V측정에서 SBH는 선형적으로 감소하고 C-V측정에서 SBH는 온도에 따른 변화가 관찰되지 않았다. 이것은 낮은 온도에서 열이온 방출 이론을 따르지 않는다는 것을 나타낸다. 이것으로 재결합 전류를 고려하여 계산해 본 결과 I-V에서도 SBH의 변화가 관찰되지 않으므로 C-V측정과 일치됨을 보았다. 이런 상반된 결과를 가져오는 이유는 전류수송현상이 온도에 따라 변화하므로 생긴 것임을 알 수 있었다.

• Journal of Information Display
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• 제10권3호
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• pp.101-106
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• 2009

In this study, a physical OLED analog behavior model for SPICE simulation was described using the Verilog-A language. The model was presented through theoretical equations for the J-V characteristics of OLED derived according to the internalcarrier emission equation based on a diffusion model at the Schottky barrier contact, and the mobility equation based on the Pool-Frenkel model. The accuracy of this model was examined by comparing it with the results of the device simulation that was conducted.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1212-1215
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• 2009

The theoretical equations for J-V characteristics in an OLED was derived according to the internal carrier emission equation based on a diffusion model at Schottky barrier contact and the mobility equation based on the Pool-Frenkel model. The J-V characteristics of OLED are presented using a behavioral model for analog systems (Verilog-A language), and the accuracy of this model was verified by comparing with the device simulation results.

• E2M - 전기 전자와 첨단 소재
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• 제16권9호
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• pp.61.1-61
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• 2003

Stoichiometric, uniform, amorphous ZrO$_2$ films with an equivalent oxide thickness of ∼1.5nm and a dielectric constant of ∼18 were deposited by an atomic layer controlled deposition process on silicon for potential application in meta-oxide-semiconductor(MOS) devices. The conduction mechanism is identified as Schottky emission at low electric fields and as Poole-Frenkel emission at high electric fields. the MOS devices showed low leakage current, small hysteresis(〈50mV), and low interface state density(∼2*10e11/cm2eV). Microdiffraction and high-resolution transmission electron microscopy showed a localized monoclinic phase of ${\alpha}$-ZrO$_2$ and an amorphous interfacial ZrSi$\_$x/O$\_$y/ layer which has a correspondign dielectric constant of 11

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.270-274
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• 1997

The numerical model that can describe the ignition of the pseudospark discharge using hybrid fluid-particle method has been developed. The evolution process of the discharge has been divided into four phases along the potential distribution. After the plasma enters in the hollow cathode, the confining effect which is one of hollow cathode properties occurs and the electron current on anode rises rapidly. As the plasma expands successively, the sheath contracts and as the electric field in the sheath increases, the field-enhanced thermionic emission(Schottky emission) occurs. From numerical results, the physical mechanism that causes the rapid current rise in the ignition of the pseudospark discharge could be identified.