• 한국전기전자재료학회논문지
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• 제25권6호
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• pp.409-413
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• 2012

In this study, a substrate-bias assisted 2-step pulse programming method is proposed for realizing 4-bit/1-cell operation of the SONOS memory. The programming voltage and time are considerably reduced by this programming method than a gate-bias assisted 2-step pulse programming method and CHEI method. It is confirmed that the difference of 4-states in the threshold voltage is maintained to more than 0.5 V at least for 10-year for the multi-level characteristics.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 추계종합학술대회 논문집
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• pp.703-706
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• 1998

This paper presents an efficient substrate-bias generator(SBG)for low-power, high-density DRAM's The proposed SBG can supply stable voltage with switching the supply voltage of driving circuit, and it can substitude the small capacitance for the large capacitance. The charge pumping circuit of the SBG suffere no VT loss and is to be applicable to low-voltage DRAM's. Also it can reduce the power consumption to make VBB because of it's high pumping efficiency. Using biasing voltage with positive temperature coefficient, VBB level detecting circuit can detect constant value of VBB against temperature variation. VBB level during VBB maintaining period varies 0.19% and the power dissipation during this period is 0.16mw. Charge pumping circuit can make VBB level up to -1.47V using VCC-1.5V, and do charge pumping operation one and half faster than the conventional ones. The temperature dependency of the VBB level detecting circuit is 0.34%. Therefore the proposed SBG is expected to supply a stable VBB with less power consumption when it is used in low power DRAM's.

• 조명전기설비학회논문지
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• 제23권1호
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• pp.78-84
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• 2009

본 연구에서는 ZnO:Al 박막의 필름형 염료감응 태양전지의 투명전도막으로의 웅용 가능성을 연구하기 위하여 PET 기판 위에 r. f. 마그네트론 스퍼터링법으로 ZnO:Al 박막을 증착하였으며, ZnO:Al 박막의 전기적 그리고 광학적 특성의 향상을 위하여 기판 바이어스 전압을 인가하였다. 그 결과, 정(+)의 기판 바이어스 전압은 플라즈마 중의 전자를 기판의 스퍼터 원자에 충돌하게 함으로써 박막에 부가적인 에너지를 공급하게 되어 박막의 결정성장 및 전기적 특성을 향상시키고 있음을 알 수 있었다. 그러나 +30[V] 이상의 과도한 기판 바이어스 전압을 인가한 경우, 박막의 전기적 특성은 나빠졌으며, 특히 부(-)의 바이어스 전압을 인가한 경우 결정 성장이 나타나지 알아, 전기적 특성의 향상을 위한 기판 바이어스 전압의 효과가 매우 제한적으로 작용되고 있음을 알 수 있었다. 본 연구에서는 +30(V)의 기판 바이어스 조건하에서 $1.8{\times}10^{-3}[{\Omega}-cm]$의 체적 저항율 및 87.77(%)의 광 투과율을 얻을 수 있었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1260-1261
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• 2008

Aluminium doped zinc oxide (ZnO:Al) thin film has emerged as one of the most promising transparent conducting electrode in flat panel displays(FPD) and in photovoltaic devices since it is inexpensive, mechanically stable, and highly resistant to deoxidation. In this paper ZnO:Al thin film was deposited on the polyethylene terephthalate(PET) substrate by the capacitively coupled r.f. magnetron sputtering method. Wide ranges of bias voltage, -30V${\sim}$45V, was applied to the growing films as an additional energy instead of substrate heating, and the effect of positive and negative bias on the film structure and electrical properties of ZnO:Al films was studied and discussed. The results showed that a bias applied to the substrate during sputtering contributed to the improvement of electrical properties of the film by attracting ions and electrons in the plasma to bombard the growing films. These bombardments provided additional energy to the growing ZnO film on the substrate, resulting in significant variations in film structure and electrical properties. The film deposited on the PET substrate at r. f. discharge power of 200 W showed the minimum resistivity of about $2.4{\times}10^{-3}{\Omega}-cm$ and a transmittance of about 87%.

• 한국진공학회지
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• 제13권2호
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• pp.79-85
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• 2004

본 논문은 구리와 탄탈 박막내에 불순물로써 함유되기 쉬운 수소와 탄소, 그리고 산소 원소에 대해 이차이온 질량분석기(secondary ion mass spectrometry)와 글로우방전 질량분석기(glow discharge mass spectrometry)를 이용하여 분석하였고, 이들의 분석결과에 대해서 고찰하였다. 구리와 탄탈 박막은 실리콘 기판 위에 비질량 분리형 이온빔 증착장비를 이용하여 기판 바이어스를 걸지 않은 경우와 -50 V(구리 박막) 또는 -125 V(탄탈 박막)의 기판바이어스를 걸은 상태에서 증착하였다. 세슘 이온빔을 이용하여 분석한 SIMS 결과에서, 기판 바이어스를 걸지 않은 경우, 상당히 많은 피크들이 강하게 관찰되었는데 이는 위의 주요불순물들의 결합에 의한 상태로 검출된 것으로 이들 주요불순물들의 조합에 의해 가능한 질량번호를 산출하여 SIMS 결과의 모든 피크들을 해석할 수 있었다. 또한, 박막 내의 주요불순물들의 정량적인 GDMS 분석에 의해 SIMS 결과와의 일치성을 확인할 수 있었다.

• 한국진공학회지
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• 제10권1호
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• pp.119-126
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• 2001

ECR-PECVD 방법으로 ECR 플라즈마 소스 power, $CH_4/H_2$ 가스 혼합비와 유량, 증착시간 및 기판 bias 전압을 변화시켜 가면서 수소가 함유된 비정질 탄소 박막을 증착하고, 증착조건에 따라서 박막 내부에 함유되어 있는 수소함량 변화를 2.5 MeV 헬륨 이온빔을 사용하는 ERDa로 측정하였다. ERDA의 결과와 hES 및 RBS에 의한 성분분석으로부터 본 실첨에서 증착된 박막은 탄소와 수소만으로 구성 되어있음을 확인할 수 있었고, FTIR의 결과로부터 박막 증착조건에 따라서 박막 내부에 함유되어 있는 수소함량이 변화함을 알 수 있었다. 기판 bias 전압을 증가시킬수록 이온충돌 현상이 두드러져 탄소와 결합하고 있던 수소원자들이 떨어져 나가는 탈수소화 현상으로 수소함량이 크게 감소됨을 알 수 있었다. 그 밖의 조건에서는 박막증착 초기에는 수소보다 탄소량이 좀 더 많다가 점차적으로 수소함량이 증가되었고, 이때 박막 내부에 함유되어 있는 수소함량은 45~55% 범위 내에 있음을 확인할 수 있었다.

• 한국초전도ㆍ저온공학회논문지
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• 제14권1호
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• pp.1-3
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• 2012

LMO($LaMnO_3$) buffer layer of superconducting coated conductor was deposited on IBAD-MgO template in the plasma atmosphere at $650^{\circ}C$ which is relatively low compared with conventional deposition temperature of more than $800^{\circ}C$. Deposition method of LMO was DC sputtering, and target and deposition chamber were connected to the cathode and anode respectively. When DC voltage was applied between target and chamber, plasma was formed on the surface of target. The tape substrate was located with the distance of 10 cm between target and tape substrate. When anode bias was connected to the tape substrate, electrons were attracted from plasma in target surface to the tape substrate, and only tape substrate was heated by electron bombardment without heating any other zone. The effect of electron bombardment on the surface of substrate was investigated by increasing bias voltage to the substrate. We found out that the sample of electron bombardment had the effect of surface heating and had good texturing at low controlling temperature.

• Journal of Ceramic Processing Research
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• 제17권7호
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• pp.763-767
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• 2016

The structural characterization of cubic boron nitride (c-BN) thin films was performed using a B4C target in a radio-frequency magnetron sputtering system. The deposition processing conditions, including the substrate bias voltage, substrate temperature, and base pressure were varied. Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy were used to analyze the crystal structures and chemical binding energy of the films. For the BN film deposited at room temperature, c-BN was formed in the substrate bias voltage range of -400 V to -600 V. Less c-BN fraction was observed as the deposition temperature increased, and more c-BN fraction was observed as the base pressure increased.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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• pp.55-58
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• 1996

A new type CuN/Cu/CuN thin film electrode material with high adhesion to glass was developed by the dc reactive planar magnetron sputtering system for the PDP(Plasma Display Panel). The adhesive force of the CuxN thin film was in the range of 20∼40(N) under the conditions of the N$_2$ partial pressure of 15%, discharge current of 70mA, discharge voltage of 450v and substrate bias voltage of -100V. The adhesive force was depended on the N$_2$ partial Pressure, discharge current and substrate bias voltage.

• Journal of Advanced Marine Engineering and Technology
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• 제18권2호
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• pp.54-63
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• 1994

Mg thin films were prepared on SPCC(cold-rolled steel) substrates by vasuum evapoaration and ion-plating. The influence of argon gas pressure and substrates bias voltage on the crystal orientation and morphology of the film was determined by using X-ray diffraction and scanning electron micrography (SEM), respectively. And the effect of crystal orientation and morphology of the Mg thin films on corrosion behavior was estimated by measuring the anodic polarization curves in deaerated 3% NaCl solution. The crystal orientation of the Mg films deposited at high argon gas pressure exhibited a (002) preferred orientation, regardless of the substrate bias voltage. Film morphology changed from a columnar to a granular structure with the increase of argon gas pressure. The morphology of the films depended not only on argon gas pressure but also bias voltage ; i.e., the effect of increasing bias voltage was similar to that of decreasing argon gas pressure. The influences of argon gas pressure and bias voltage were explained by applying the adsorption inhibitor theory and the sputter theory. And also, this showed that the corrosion resistance of the Mg thin films can be changed by controlling the crystal orientaton and morphology.