비진공 방법에 의한 CIGS/CZTS계 박막 태양전지 제조

유다영,이동윤,Yoo, Dayoung,Lee, Dongyun 한국재료학회 2018 한국재료학회지 Vol.28 No.12

Inorganic semiconductor compounds, e.g., CIGS and CZTS, are promising materials for thin film solar cells because of their high light absorption coefficient and stability. Research on thin film solar cells using this compound has made remarkable progress in the last two decades. Vacuum-based processes, e.g., co-evaporation and sputtering, are well established to obtain high-efficiency CIGS and/or CZTS thin film solar cells with over 20 % of power conversion. However, because the vacuum-based processes need high cost equipment, they pose technological barriers to producing low-cost and large area photovoltaic cells. Recently, non-vacuum based processes, for example the solution/nanoparticle precursor process, the electrodeposition method, or the polymer-capped precursors process, have been intensively studied to reduce capital expenditure. Lately, over 17 % of energy conversion efficiency has been reported by solution precursors methods in CIGS solar cells. This article reviews the status of non-vacuum techniques that are used to fabricate CIGS and CZTS thin films solar cells.

비 유리식(non-glass) 단일 진공관형 태양열 집열기의 설계

현준호(Hyun Jun-Ho),오승진(Oh Seung-Jin),김남진(Kim Nam-Jin),천원기(Chun Won-Gee) 한국태양에너지학회 2007 한국태양에너지학회 학술대회논문집 Vol.- No.-

This paper introduces design of a non-glass solar vacuum tube collector where a heat pipe is used to transfer the heat collected from impinging solar rays. A series of tests have been performed to assess the effects of air pressure inside the vacuum tube. It is not yet certain, however, what should be the level of vacuum maintained inside the vacuum tube and how much it affects the heat loss to the ambient. More work is under way to systematically assess the magnitude of convection compared to other modes of heat transfer.

온도 기울기에 의한 빛의 굽어짐

김진영,이태균 한국물리학회 2013 새물리 Vol.63 No.11

Because classical electrodynamics is linear, the vacuum is unique and trivial. In a classical vacuum, the speed of light is constant. In quantum electrodynamics, the vacuum expectation value of the electromagnetic current can be non-zero due to non-charge-like sources, like electric fields, magnetic fields, gravitational fields, temperature fields, etc. We consider the velocity shift of light due to the vacuum polarization effect of quantum electrodynamics when the temperature is finite. The speed of light in this non-trivial vacuum is different from that in a trivial vacuum at zero temperature. This means that the index of refraction is not one. We set up a model to find the trajectory and the bending angle of a light ray when the index of refraction has a gradient. We compute the bending angles when the gradient is spherically symmetric and when it is cylindrically symmetric. For a magnetized neutron star, We compare that bending angle with the bending angles caused by gravitation and electromagnetic field. 고전적인 전자기 이론은 선형이므로 진공은 유일하고 뻔하여 빛의 속도는 일정하고 직진한다. 양자전기역학적으로는 전기장, 자기장, 중력장, 온도 등과 같이 다양한 비전하적 근원에 의해 전자기 흐름의 진공기대값이 영이 되지 않을 수 있어 진공이 뻔하지 않게 될 수 있다. 유한한 온도에 의해 생기는 양자전기역학적 진공편극 효과에 의해 진공이 뻔하지 않은 경우 빛의 속력은 뻔한 진공에서의 빛의 속력과 다르게 되고 굴절률이 1이 아니다. 본 연구에서는 온도기울기에 의해 굴절률이 연속적으로 변하는 공간을 진행하는 빛의 경로와 휘어지는 각도를 기하광학으로 계산하는 방법을 모형화하였다. 온도기울기가 구대칭인 경우와 원통대칭인 경우 빛이 휘어지는 각도들을 구하였다. 자화된 중성자별에 적용하여 중력에 의해 휘어지는 각도 및 전자기장에 의해 굽어지는 경우와 비교해 보았다.

Analysis of a Non-Evaporable Getter of Ti-Al-Zr Thin Film with Enhanced Performance Used for Ultra-High Vacuum Generation

Muhammad Khalid Alamgir,M. Ikram,Ghalib Hussain Mughal,Ghulam Asghar,Sha q ur Rehman,S. Qaseem,M. Kamran,Amir Ullah,Sartaj Khan 한국물리학회 2019 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.75 No.5

Non-evaporable getter (NEG) thin films of Ti-Al-Zr and Ti-Zr were prepared on stainless-steel substrate by using the cathodic arc deposition technique. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and in-situ X-ray photoelectron spectroscopy (XPS) were used to analyze the getter behavior of the non-evaporable getter thin films. The SEM images displayed the porous and rough surfaces of the thin films, which is an indication of high adsorption and sticking probabilities for the residual gases present in the chamber. The volume elemental composition of the thin films was measured by using EDX. The XRD patterns of the synthesized thin films indicated that the films had an amorphous nature and high structural stability. The in-situ X-ray photoelectron spectroscopy (XPS) studies revealed that the superficial layers disappeared when the non-evaporable getter of Ti-Al-Zr thin films was heated at a temperature below 250~$^\circ$C for 30 minutes, there by activating the surface. However, for Ti-Zr thin films, no reasonable activation was observed at 250~$^\circ$C. This outcome reveals that thin films of Ti-Al-Zr are good for reducing the outgassing and producing an ultra-high vacuum.

Vacuum infiltration transformation of non-heading Chinese cabbage (Brassica rapa L. ssp. chinensis) with the pinII gene and bioassay for diamondback moth resistance

Zhang, Junjie,Liu, Fan,Yao, Lei,Luo, Chen,Zhao, Qing,Huang, Yubi The Korean Society of Plant Biotechnology 2011 Plant biotechnology reports Vol.5 No.3

Non-heading Chinese cabbage (Brassica rapa L. ssp. chinensis) is a popular vegetable in Asian countries. The diamondback moth (DBM), Plutella xylostella (L.), an insect with worldwide distribution, is a main pest of Brassicaceae crops and causes enormous crop losses. Transfer of the anti-insect gene into the plant genome by transgenic technology and subsequent breeding of insect-resistant varieties will be an effective approach to reducing the damage caused by this pest. We have produced transgenic non-heading Chinese cabbage plants expressing the potato proteinase inhibitor II gene (pinII) and tested the pest resistance of these transgenic plants. Non-heading Chinese cabbages grown for 45 days on which buds had formed were used as experimental materials for Agrobacterium-mediated vacuum infiltration transformation. Forty-one resistant plants were selected from 1166 g of seed harvested from the infiltrated plants based on the resistance of the young seedlings to the herbicide Basta. The transgenic traits were further confirmed by the Chlorophenol red test, PCR, and genomic Southern blotting. The results showed that the bar and pinII genes were co-integrated into the resistant plant genome. A bioassay of insect resistance in the second generation of individual lines of the transgenic plants showed that DBM larvae fed on transgenic leaves were severely stunted and had a higher mortality than those fed on the wild-type leaves.

Non-vacuum deposition of CIGS absorber films for low-cost thin film solar cells

이동욱,용기중 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.7

Thin film solar cells composed of chalcopyrite Cu(In1−xGax)(Se1−ySy)2 (CIGSSe) absorbers have gained considerable attention in recent years in an effort to develop sustainable technologies for harnessing clean energy. Nonvacuum solution methods can reduce production costs by replacing vacuum-based deposition methods with large-scale,high-throughput processes. The efficient use of materials can reduce production costs. Non-vacuum processes generally rely on two sequential steps: solution-coating, followed by a post-annealing process. Depending on the point at which the CIGS phase evolves, non-vacuum processes can be categorized as nanoparticle (NP) approaches or molecular precursor approaches. These two types of liquid processes are believed to be compatible with a variety of applications,such as roll-to-roll coating for the production of flexible, portable devices. Additional thermal treatments using a gaseous chalcogen or oxygen can improve the absorber quality. This review describes the current status of chalcopyrite thin film solar cells fabrication methods via low-cost solution routes. An analysis of recently published reports describing liquid-based deposition methods is introduced, and the features of the development steps are compared. Finally, a discussion and future outlook are offered.

비유리식(nonglass) 진공관의 진공도가 집열판의 열적 특성에 미치는 영향

오승진(Oh Seung-Jin),현준호(Hyun Jun-Ho),김남진(Kim Nam-Jin),이윤준(Lee Yoon-Joon),천원기(Chun Won-Gee) 한국태양에너지학회 2008 한국태양에너지학회 논문집 Vol.28 No.3

This study has been carried out to investigate the effect of vacuum on the thermal performance of a nonglass evacuated tube. A series of measurements are made indoors to monitor the temperature change of the absorber plate contained in the evacuated tube under different conditions of vacuum and heat fluxes. Those temperatures measured at the thermal equilibrium could be used to assess the heat losses to the ambient in link with the steady operation of non-glass evacuated tubes for solar exploitation.

가정용 냉장고의 불응축 가스량에 따른 소비 전력 특성

김두현(Doohyun Kim),황유진(Yujin Hwang),박재홍(Jae-Hong Park),정성일(Seong-Ir Chung),정영만(Young-Man Jeong),구본철(Bon-Cheol Ku),이재근(Jae-Keun Lee),안영철(Young-Chull Ahn),방선욱(Sunwook Bang),김석로(Seok-Ro Kim) 대한설비공학회 2008 설비공학 논문집 Vol.20 No.6

The presence of non-condensable gases as an additional thermal resistance inside a refrigerating circuit has been found for a general refrigerator. The effect of non-condensable gases was varied by controlling the injection amount of dry air into the refrigerating circuit to increase a thermal resistance. Energy consumption tests for the refrigerator were conducted under the various amounts of non-condensable gases. The tested refrigerating circuit was the household refrigerator. As the molar fraction of non-condensable gases was increased from 0% to 1.46%, the amount of energy consumption was found to increase up to 25%. The increase of the amount of non-condensable gases in refrigerating circuit was found to result in increasing the condensation temperature at the condenser and decreasing the evaporation temperature at the evaporator, which were presumably caused by the low specific heat and increased partial pressure of non-condensable gas.

UV NIL공정에서 액적의 양과 도포방법에 따른 기포형성 연구

이기연(Lee, Ki-Yeon),김국원(Kim Kug Weon) 한국산학기술학회 2013 한국산학기술학회논문지 Vol.14 No.9

최근 나노임프린트 리소그래피 공정이 마이크로/나노 스케일의 소자 개발에 있어서 경제적으로 대량 생산할 수 있는 기술로 주목 받고 있다. 최근 나노임프린트 기술은 공정의 고속화 및 대면적화를 통한 대량생산 기술로의 전 환을 목표로 하고 있다. 자외선경화 방식의 나노임프린트의 경우 상온 및 저압의 장점과 함께 비진공 환경에서 공정 이 가능하다면 진공챔버 및 고압 스테이지 등과 같은 고가의 장비가 필요 없게 됨으로써 설비비용을 낮추고 공정시 간을 단축하는데 큰 기여를 할 수 있다. 그러나 비진공 환경에서는 기포결함이 종종 발생하게 된다. 본 연구에서는 비진공 환경에서의 자외선경화 방식의 나노임프린트 공정 중 레지스트의 액적도포 방법에 따른 기포형성을 연구하였 다. 액적의 양과 액적의 수를 달리하여 도포한 레지스트에 대하여 충전 후 기포결함 발생을 분석하였다. Nanoimprint lithography (NIL) is an emerging technology enabling cost-effective and high-throughput nanofabrication. Recently, the major trends of NIL are high throughput and large area patterning. UV curable type NIL (UV NIL) can be performed at room temperature and low pressure. And one advantage of UV NIL is that it does not need vacuum, which greatly simplifies tool construction, so that vacuum oprated high-precision stages and a large vacuum chamber are no longer needed. However, one key issue in non-vacuum environment is air bubble formation problem. Namely, can the air bubbles be completely removed from the resist. In this paper, the air bubbles formation by the method of droplet application in UV NIL with non-vacuum environment are experimentally studied. The effects of the volume of droplet and the number of dispensing points on air bubble formation are investigated.

Preparation and Characterization of Platinum Nanoparticles Supported by Non-woven Fabric for Formaldehyde Decomposition

Gaodan Luo,Qian Yu,Lin Yu,Xiaorui Wang,Xiuqing Hao,Jing Fu 한국섬유공학회 2019 Fibers and polymers Vol.20 No.10

Vacuum adsorption was employed to synthesize platinum/polyethylene terephthalate (PET) samples with greatpotential for indoor air quality improvement application. Pt nanoparticles (PNPS) were loaded onto surface of non-wovenfabric composed of polyethylene terephthalate (PET) and with high air permeability. High activity was sought for the Pt/PETcatalyst by investigating the effects of hexadecyl trimethyl ammonium bromide (CTAB) on PNP sizes and PET fibersurfaces. The prepared samples were characterized by XRD, SEM, TEM, TG, FTIR and XPS analysis. The results indicatedthat Pt/PET samples were successfully fabricated, and a formaldehyde conversation of 70.8 % was obtained within 150 minat 35 oC using Pt/PET with 0.6 wt% Pt loading. This research provided a facile method for depositing Pt onto PET fibers(non-woven fabric), and the catalytic activities of the resulting composite Pt/PET materials indicated them to be promisingfor applications to indoor air remediation.