• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.549-552
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• 1998

Recently, the gate oxide damage induced by the plasma processes has been one of the most significant reliability issues as the gate oxide thickness falls below 10 nm. The process-induced damage was studied with the metal antenna test structures. In addition to the electron trapping, the hole trapping in a 10 nm thick gate oxide due to the plasma-induced charging was observed in the NMOS's with a metal antenna. The hole trapping gave rise to the decrease of the transconductance (gm) similarly to the case of the electron trapping, but to the extent much less than the electron trapping. It would be because the electrical stress that the plasma-induced charging forced to the gate oxide for the devices with the hole trapping was much smaller than for those with the electron trapping. This hypothesis was strongly supported by the measured characteristics of the Fowler-Nordheim current in the gate oxide.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.36D no.3
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• pp.34-40
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• 1999

Recently, the gate oxide damage induced by the plasma processes has been one of the most significant reliability issues as the gate oxide thickness falls below 10 nm. The plasma-induced damage was studied with the metal antenna test structures. In addition to the electron trapping, the hole trapping in a 10 nm thick gate oxide due to the plasma-induced charging was observed in the NMOS's with a metal antenna. The hole trapping caused the transconductance (gm) to be reduced like the case of the electron trapping, but to the extent much less than the electron trapping. It would be because the electrical stress that the plasma-induced charging forced to the gate oxide for the devices with the hole trapping was much smaller than for those with the electron trapping. This hypothesis was strongly supported by the measured characteristics of the Fowler-Nordheim current in the gate oxide.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.557-558
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• 2006

In this paper, the hysteresis characteristics by bias stress in organic thin film transistors using inkjet printing were investigated. Electron trapping increased threshold voltage for positive gate bias stress and hole trapping decreased threshold voltage for negative gate bias stress. From these phenomena, highly reproducible measurement method which minimized threshold voltage shift by choosing the proper range of gate voltage was suggested. Using this measurement method, we found that electron trapping as well as hole trapping had important influence on hysteresis characteristics.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.1047-1052
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• 2003

Controlling carrier transport in light emitting polymers is extremely important for their efficient use in organic opto-electronic devices [1]. Here we show that the interactions between single wall carbon nanotubes (SWNTs) and conjugated polymers can be used to modify the overall mobility of charge carriers within nanotube-polymer nanocomposites. By using a unique, double emitting-organic light emitting diodes (DE-OLEDs) structure. we have characterized the hole transport within electroluminescent nanocomposites (nanotubes in poly (m-phenylene vinylene-co-2,5-dioctoxy-p-phenylene) or PmPV). We have shown using this idea that single devices with color tunability can be fabricated. It is seen that SWNTs in PmPV are responsible for hole trapping, leading to shifts in the emission wavelengths. Our results could lead to improved organic optical amplifiers, semiconducting devices, and displays.

• Electrical & Electronic Materials
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• v.6 no.2
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• pp.115-120
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• 1993

본 연구에서는 dry oxide와 wet oxide로 MOS capacitor를 제작하여 avalanche 전자주입 실험으로 산화막의 캐리어 트랩핑특성을 조사하였다. dry oxide에서는 avalanche 전자주입 시 전자 trapping이 주도적으로 일어났다. wet oxide에서는 주입 초기에 전자 trapping이 주도적이다가 hole trapping이 주도적으로 바뀌게 되는 turn-around 현상이 일어났다. 주입시간이 길어지면 다시 전자 trapping이 주도적으로 되는 또 한번의 turn-around 현상이 일어났다. 산화막의 트랩 parameter를 결정하기 위해 실험결과를 기초로 하여 종류가 다른 여러 트랩을 가지는 계에 대한 캐리어 트랩핑 이론식을 세워서 실험결과와 curve-fitting한 결과 실험치와 잘 일치하는 곡선을 얻었다.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1404-1407
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• 2005

We have fabricated organic light-emitting diodes using poly(N-vinylcarbazole)(PVK) doped with N,N'- diphenyl-N,N'-bis(3-methylphenyl)-[l,l'-biphenyl]- 4,4/-diamine (TPD) as the hole transport layer. TPD molecules act as the trapping sites in PVK and reduce the hole mobility, which can enhance the electronhole balance in the emitting layer, resulting in the enhanced device performance. We have found the optimum ratio of TPD to PVK for the EL efficiency.

• Electrical & Electronic Materials
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• v.8 no.3
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• pp.357-361
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• 1995

An experiment on characteristics of nMOSFET's in the long stress condition with the maximum of the substrate current has been carried out in order to study on the degradation due to the hot-carrier effect. Based on the measured result of the threshold voltage, the damage is mostly due to the hole injection into the oxide. After long stress, it was shown that the drain current increased at low gate voltages and hence decreased at high gate voltages.

• JSTS:Journal of Semiconductor Technology and Science
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• v.15 no.5
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• pp.526-532
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• 2015

We quantitatively investigated instability mechanisms under simultaneous positive gate and drain bias stress (SPGDBS) in self-aligned top-gate amorphous indium-zinc-oxide thin-film transistors. After SPGDBS ($V_{GS}=13V$and $V_{DS}=13V$), the parallel shift of the transfer curve into a negative $V_{GS}$ direction and the increase of on current were observed. In order to quantitatively analyze mechanisms of the SPGDBS-induced negative shift of threshold voltage (${\Delta}V_T$), we experimentally extracted the density-of-state, and then analyzed by comparing and combining measurement data and TCAD simulation. As results, 19% and 81% of ${\Delta}V_T$ were taken to the donor-state creation and the hole trapping, respectively. This donor-state seems to be doubly ionized oxygen vacancy ($V{_O}^{2+}$). In addition, it was also confirmed that the wider channel width corresponds with more negative ${\Delta}V_T$. It means that both the donor-state creation and hole trapping can be enhanced due to the increase in self-heating as the width becomes wider. Lastly, all analyzed results were verified by reproducing transfer curves through TCAD simulation.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.687-690
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• 2003

Experimental results are presented for gate oxide degradation and its effect on device parameters under negative and positive bias stress conditions using NMOSFET's with 3 nm gate oxide. The degradation mechanisms are highly dependent on stress conditions. For negative gate voltage, both hole- and electron-trapping are found to dominate the reliability of gate oxide. However, with changing gate voltage polarity, the degradation becomes dominated by electron trapping. Statistical parameter variations as well as the "OFF" leakage current depend on those charge trapping. Our results therefore show that Si or O bond breakage by electron can be another origin of the investigated gate oxide degradation.gradation.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.8
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• pp.1-8
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• 2004

Experimental results are presented for gate oxide degradation, such as SILC and soft breakdown, and its effect on device parameters under negative and positive bias stress conditions using n-MOSFET's with 3 nm gate oxide. The degradation mechanisms are highly dependent on stress conditions. For negative gate voltage, both interface and oxide bulk traps are found to dominate the reliability of gate oxide. However, for positive gate voltage, the degradation becomes dominated mainly by interface trap. It was also found the trap generation in the gate oxide film is related to the breakage of Si-H bonds through the deuterium anneal and additional hydrogen anneal experiments. Statistical parameter variations as well as the “OFF” leakage current depend on both electron- and hole-trapping. Our results therefore show that Si or O bond breakage by tunneling electron and hole can be another origin of the investigated gate oxide degradation. This plausible physical explanation is based on both Anode-Hole Injection and Hydrogen-Released model.