Search

틱이란 불수의적이고 갑작스러운 소리냄과 리듬이 없는 근육의 움직임을 말한다. 다수의 운동틱과 한 가지 이상의 음성틱이 모두 존재하는 경우 뚜렛 증후군으로 분류되며, 운동틱에 의한 자해 행위는 뚜렛 증후군 환자에서 흔히 나타나는 증상 중 하나이다. 본 증례에서 9세 소년이 혀의 심각한 궤양을 주소로 신경정신과...

We investigated the effect of adding oxygen (O2) gas to argon (Ar) gas and varying the sputter target power during intrinsic ZnO sputtering on the photovoltaic performance of Cu(In,Ga)Se2 (CIGS) solar cells. Sputtering powers of 50, 100, 150 W were used in conjunction with an O2 fraction of 0 % or 2 % in the sputtering gas. Both increasing the power and adding oxygen improved the photovoltaic conversion efficiency, although the effect of the latter was more pronounced. The results showed that the open-circuit voltage, short-circuit current density, and fill factor were all improved, and the series resistance was reduced. Electroluminescence spectroscopy and electron-beam-induced current analysis showed that adding oxygen and increasing the power not only improved the CdS/CIGS junction properties, but also the CIGS bulk properties. The current-voltage characteristics at low temperature indicated that adding oxygen and increasing the power facilitated local secondary diode formation around the CIGS surface. It was also revealed that the sodium doping concentration was enhanced by oxygen addition and increased power, with this enhancement being larger for the former. The improvements in the CdS/CIGS junction and CIGS bulk properties were therefore tentatively attributed to an enhancement of the Na doping level.

We investigated the impact of incorporating 2% oxygen during intrinsic ZnO sputtering on the efficiency of Cu(In,Ga)Se2 solar cells. The added oxygen not only reduced the optical absorption loss of the Al-doped ZnO overlaying layer but also improved the electronic properties of the underlying CdS/Cu(In,Ga)Se2 by increasing carrier density, lowering defect level, and increasing diffusion length, eventually enhancing JSC, VOC, and fill factor. It was found that the Na doping concentration was significantly increased around the CdS/Cu(In,Ga)Se2 junction due to the plasma-activated oxygen. The improved electronic properties are better explained by the increased Na concentration than simply the oxygen-related defect passivation.

The ferroelastic phase in hydrogen-bonded TlH2PO4 was investigated by means of impedance spectroscopy. The high-temperature dielectric susceptibility revealed the corresponding Curie-Weiss temperature to be far above the antiferroelectric phase transition temperature, and a phase boundary has been identified and confirmed by the distinct electric field dependencies of the polarization.