• Current Photovoltaic Research
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• 제3권4호
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• pp.130-134
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• 2015

The high efficiency cell research processes through the KF post deposition treatment (PDT) of the $Cu(In,Ga)Se_2(CIGS)$ thin film has been very actively progress. In this study, it CIGS thin film deposition process when KF PDT 300 to the processing temperature, 350, $400^{\circ}C$ changed to soda-lime glass (SLG) efficiency of the CIGS thin film characteristics, and solar cell according to Na presence of diffusion from the substrate the effects were analyzed. As a result, the lower the temperature of KF PDT and serves to interrupt the flow of current K-CIGS layer is not removed from the reaction surface, FF and photocurrent is decreased significantly. Blocking of the Na diffusion from the glass substrate is significantly increased while the optical voltage, photocurrent and FF is a low temperature (300, $350^{\circ}C$) in the greatly reduced, and in $400^{\circ}C$ tend to reduce fine. It is the presence of Na in CIGS thin film by electron-induced degradation of the microstructure of CIGS thin film is expected to have a significant impact on increasing the hole recombination rate a reaction layer is formed of the K elements in the CIGS thin film surface.

• Current Photovoltaic Research
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• 제3권2호
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• pp.65-70
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• 2015

We applied KF on CIGS film to modify CIGS surface with a wider-bandgap surface layer. With the KF deposition the surface of CIGS film had fine particle on the CIGS surface at 350 and $300^{\circ}C$. No fine particle was detected at 500 and $250^{\circ}C$. With the KF treatment, the Ga and O content increased at the surface, while the In and Cu content decreased. The valence band maximum was lowered with KF treatment. The composition profile and band structure were positive side of applying KF on the CIGS surface. However, the efficiency decreased with the KF treatment due to high series resistance, probably due to too thick surface layer. A smaller amount of KF should be supplied and more systematic analysis is necessary to obtain a reproducible higher efficiency CIGS solar cells.

• Current Photovoltaic Research
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• 제6권2호
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• pp.56-61
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• 2018

In this study, CIGS absorber layers were deposited on low-alkali glass and sodalime glass substrates and potasium floride (KF) of various thicknesses was supplied at an elevated temperature after the CIGS growth. The effect of KF post-deposition treatment on the two types of substrates was extremely different. On the low-alkali substrate, the open-circuit voltage (Voc) was improved but the fill-factor (FF) degradation was severe, whereas the sodalime substrate showed Voc deterioration and FF improvement. In the case of supplying 20 nm of KF on both substrates, the efficiency gain of 0.3~1.1%p was obtained. With increasing the KF thickness, a small protrusion-like microstructure developed on the surface of the absorber layer, and the microstructures that were not removed in the subsequent process were found to be the main cause of the FF loss.

• 공업화학
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• 제17권4호
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• pp.361-368
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• 2006

본 연구는 독립적 기공(또는 기포)을 함유하고 특히, $50kg_f/cm^2$의 압력에도 외형의 변화가 없고, 상온의 액화석유가스 (liquefied petroleum gas; LPG)에 72 h 침적시 무게 변화율이 5 wt% 이내인 LPG 고압 탱크용 발포 부표의 제조 기술을 개발하는데 목적이 있다. 각각의 다른 유황(325 Mesh와 400 Mesh)과 발포제(foaming agent)로 제조된 부표의 내압침적 실험에서 무게 변화율은 큰 차이를 보이지 않았으나 유황 400 Mesh와 발포제 AC를 이용한 부표의 기공이 더 작고 독립 기포율이 높았다. $50kg_f/cm^2$ 수압 실험에서 중립열분해(medium thermal; MT) 카본을 사용한 부표가 중보강성(semi reinforcing furnace; SRF) 카본보다 작은 무게 변화율을 나타내었다. 또한, 제조된 부표를 후처리($60^{\circ}C$, 24 h)한 경우 부표내 기공벽의 경도와 내압성이 증가되었다. 한편, 제조된 부표의 비중 0.30 이하인 제품은 찌그러지거나 깨지는 현상이 발생하고 비중이 0.35 이상으로 높으면 부력이 떨어져 부표로서 기능을 하지 못하였다. 그러므로, $50kg_f/cm^2$의 내압성을 가지기 위해서는 비중이 0.30~0.35인 부표가 가장 우수한 성능을 갖는 것으로 판단되었다.