The Characteristics of CIGS Thin-Film Solar Cells Using Sputtering Based Two-Step Process

Young-Ill Kim,Dong-Hwan Jeon,Si-Nae Park,Se-Yun Kim,Dae-Hwan Kim,Jin-Kyu Kang,Shi-Joon Sung,Juran Kim,William Jo,Hyesun Yoo,JunHo Kim,Dae-Hwan Kim,Kee-Jeong Yang 한국신재생에너지학회 2019 AFORE Vol.2019 No.11

High photo-conversion efficiency Cu₂ZnSn(S,Se)₄ thin-film solar cells prepared by compound-precursors and metal-precursors

Kim, Juran,Kim, Gee Yeong,Son, Dae-Ho,Yang, Kee-Jeong,Kim, Dae-Hwan,Kang, Jin-Kyu,Jo, William Elsevier 2018 Solar energy materials and solar cells Vol.183 No.-

<P><B>Abstract</B></P> <P>Cu<SUB>2</SUB>ZnSn(S,Se)<SUB>4</SUB> (CZTSSe) thin-film solar cells have been fabricated by various methods. Sputtering is one of the vacuum processes that can be used for the growth of the precursors. In this study, CZTSSe thin-films that were fabricated using metal-precursors and with a high efficiency of 12.3% were examined in a comparison with CZTSSe thin-films that were fabricated using compound-precursors, whose efficiency is 9.1%. Especially, the Kelvin probe force microscopy (KPFM) analysis and local current measurement by conductive atomic force microscopy (c-AFM) show that their local electrical properties indicate completely opposite results. The grain boundaries (GBs) has a downward surface potential bending, and this repelled the minority carriers into the intragrains (IGs) in the sample from the metal-precursors. Therefore, we originally verified the differences between the carrier behaviors and the current flows on the surface.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Using different precursor materials and stacks, Cu<SUB>2</SUB>ZnSn(S,Se)<SUB>4</SUB> thin-film solar cells were fabricated. </LI> <LI> The PCE of the metal-precursor CZTSSe solar cell is 12.3%, while that of compound-precursor's is 9.1%. </LI> <LI> Downward potential bending was observed in the metal-precursor CZTSSe thin-film. </LI> <LI> Surface current was formed on the intra-grains on the metal-precursor CZTSSe thin-film. </LI> <LI> The compound-precursor CZTSSe thin-film indicated inversed results from the metal-precursor one. </LI> </UL> </P>

A simple and robust route toward flexible CIGS photovoltaic devices on polymer substrates: Atomic level microstructural analysis and local opto-electronic investigation

Kim, Kihwan,Kim, Juran,Gang, Myeng Gil,Kim, Se-Ho,Song, Soomin,Cho, Yunae,Shin, Donghyeop,Eo, Young-Joo,Jeong, Inyoung,Ahn, Seung Kyu,Cho, Ara,Kim, Jayeong,Yoon, Seokhyun,Choi, Pyuck-Pa,Jo, William,Ki Elsevier 2019 Solar energy materials and solar cells Vol.195 No.-

<P><B>Abstract</B></P> <P>In this work, copper indium gallium selenide (Cu(In,Ga)Se<SUB>2</SUB>; CIGS) absorbers were grown on polyimide (PI)/molybdenum substrates by a three-stage co-evaporation process at various temperatures, film formation was systemically studied using various advanced characterization methods such as transmission electron microscopy, micro-Raman spectroscopy, Kelvin probe force microscopy, and atom probe tomography. The CIGS films on PI were found to exhibit considerable physical and electrical variations with respect to the process temperature of three-stage co-evaporation. In particular, when the process temperature reached 400 °C, the CIGS absorber on PI began to exhibit controlled microstructure and intergrain properties. By adjusting the microstructure and intergrain properties of the absorber films by means of the process temperature of three-stage co-evaporation, flexible CIGS solar cells on PI with an efficiency of 16.7% (with anti-refection coating) were achieved.</P> <P><B>Highlights</B></P> <P> <UL> <LI> CIGS absorber films were grown on flexible polyimide/molybdenum substrates. </LI> <LI> Low-temperature three-stage process (≤440 °C) with extrinsic Na addition was used to CIGS growth. </LI> <LI> CIGS film evolution was systemically observed using advanced material characterization techniques. </LI> <LI> Highly efficient CIGS cells on flexible polyimide substrates were realized while maintaining process manufacturability. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

ASSESSING SUSTAINABLE CUSTOMER VALUE IN FASHION SOCIAL PLATFORMS

Sung Hwan Yeo,Kyung Hoon Kim,Juran Kim 글로벌지식마케팅경영학회 2015 Global Fashion Management Conference Vol.2015 No.06

A fashion social platform is a system that leverages the power of social connectivity to enable individuals to interact, accumulate information and create social values in fashion marketing. Fashion social platform participants, through their collective intelligence, give social platforms essential competence to solve economic and social issues, gather social capital, and create customer value. This study highlights the critical value of fashion social platforms and explains the relationships between knowledge sharing, social capital, and sustainable customer value. They examine (1) the effects of social network properties on knowledge sharing in fashion social platforms, (2) the effects of knowledge sharing on social capital, and (3) the effects of social capital on customer value in fashion social platforms. In the context of social platforms, this study clarifies the concept of customer value, the role of knowledge sharing, and the relationships between social capital and customer value. The study constructs a theoretical model regarding fashion social platforms and sustainable customer value that offers possible implications for fashion marketing practitioners.

INFLUENCES OF VR EXPERIENCE ON PURCHASE INTENTION

Juran Kim,Seungmook Kang 글로벌지식마케팅경영학회 2018 Global Marketing Conference Vol.2018 No.07

Virtual reality refers to an immersive computer-generated, interactive, 3D environment that offers media richness and interactivity. VR provides high media richness verified by the sensory depth and breadth of an interface. The purpose of this study is to investigate the relationships among mindsets, VR experience, perceived interactivity, attitude and purchase. This study clarifies the concept of VR experience and enlightened the relationship between VR experience, perceived interactivity, attitude and purchase intention. The study clarifies technology-driven experience, especially VR experience that can be differentiated from direct and indirect experience. The study can be a starting point to identifying how new technology boosts experiences by reflecting types of VR experience including spatial experience, presence experience, sensory experience and behavioral experience .

Nanoscale investigation of surface potential distribution of Cu2ZnSn(S,Se)4 thin films grown with additional NaF layers

Kim Gee Yeong,Kim Juran,Jo William,Son Dae-Ho,Kim Dae-Hwan,Kang Jin-Kyu 나노기술연구협의회 2014 Nano Convergence Vol.1 No.27

CZTS precursors [SLG/Mo (300 nm)/ZnS (460 nm)/SnS (480 nm)/Cu (240 nm)] were deposited by RF/DC sputtering, and then NaF layers (0, 15, and 30 nm) were grown by electron beam evaporation. The precursors were annealed in a furnace with Se metals at 590°C for 20 minutes. The final composition of the CZTSSe thin-films was of Cu/(Zn + Sn) ~ 0.88 and Zn/Sn ~ 1.05, with a metal S/Se ratio estimated at ~0.05. The CZTSSe thin-films have different NaF layer thicknesses in the range from 0 to 30 nm, achieving a ~3% conversion efficiency, and the CZTSSe thin-films contain ~3% of Na. Kelvin probe force microscopy was used to identify the local potential difference that varied according to the thickness of the NaF layer on the CZTSSe thin-films. The potential values at the grain boundaries were observed to increase as the NaF thickness increased. Moreover, the ratio of the positively charged GBs in the CZTSSe thin-films with an NaF layer was higher than that of pure CZTSSe thin-films. A positively charged potential was observed around the grain boundaries of the CZTSSe thin-films, which is a beneficial characteristic that can improve the performance of a device.

Effects of Alkali Metal Doping in the Low-Temperature Grown Cu(In,Ga)Se₂ Thin Films on Flexible Polyimide Probed by Scanning Probe Microscopy

Juran Kim,Kihwan Kim,Jihye Gwak,Jae Ho Yun,William Jo 한국신재생에너지학회 2019 AFORE Vol.2019 No.11

SUSTAINABLE MARKETING IN SOCIAL BRAND COMMUNITIES

Juran Kim 글로벌지식마케팅경영학회 2014 Global Marketing Conference Vol.2014 No.5

The purpose of this study is to offer conceptual foundations of social brand community by developing an integrated overview of the current research. Concepts from the Structuration theory are used for synthesizing the consumer behavior literature. This study attempts to find and fill the gaps between brand community and social brand community. To fill the gaps in the literature, potential research questions and future research directions are suggested. This study offers foundations to develop a conceptual model of social brand community by considering the basic concepts in the Structuration theory and critical characteristics of the social media environment.

Effects of mobile direct experience on perceived interactivity and attitude toward smartphone applications

Kim, Juran,Lee, Ki Hoon,Taylor, Charles R. Taylor Francis 2013 마케팅과학연구 Vol.23 No.3

Influences of Motivations on Interactivity in the Live Streaming Commerce

Juran KIM 한국유통과학회 2021 The Journal of Industrial Distribution & Business( Vol.12 No.10

Purpose: This study focuses how motivations influence interactivity in the live streaming commerce context. Live streaming commerce involves the provision of e-commerce activities and transactions via a live streaming platform that offers real-time interaction, entertainment, social activities, and commerce. The purpose of study is to examine effects of motivations on perceived interactivity and the effects of perceived interactivity on attitude and intention to use the live streaming commerce. Research design, data and methodology: The study investigates key questions about consumers’ motivation to use live streaming commerce and perceived interactivity by surveying 300 users of live commerce. Participants were asked whether they were live streaming commerce users who had experienced live streaming commerce before participating in the survey. The full survey required live streaming commerce users to respond to all the questions. Results: The study uncovered motivations for using live streaming commerce by finding information, entertainment, pass time, fashion/status and real time and perceived interactivity in the live streaming commerce. The results indicated motivation to use live streaming commerce positively influenced perceived interactivity. Perceived interactivity had positive effects on attitude toward brand. Attitude toward brand had positive effects on intention to use. Conclusions: Live streaming commerce is getting increasing attention from marketers because live streaming commerce has seamlessly integrated commerce, social activities, and hedonic factors. This study clarifies motivations and perceived interactivity in the live streaming commerce context. The study uncovers the relationships between motivations, perceived interactivity, attitude, and intention to use that contributes to the theoretical foundation and practical implications for marketing and management in the live streaming commerce context. Specifically, the study develops the theoretical contributions to perceived interactivity in the in the live streaming commerce context. The results also contribute to the practical implications for new marketing strategies that provides dynamic real-time interaction, exact information, and social and hedonic factors to attract consumers to indulge in the consumption processes. Marketing practitioners will obtain insights that can help them develop and manage brand strategies by understanding the influence of motivation and perceived interactivity in the live commerce context, which offers opportunities for contactless marketing and management.