http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Effective Carrier Collection in Bifacial Silicon Heterojunction Solar Cells by Band-Offset Reduction
Duy Phong Pham(강사),Hyeong Gi Park(박형기),Youngkuk Kim(김영국),Junsin Yi(이준신) 한국신재생에너지학회 2021 한국신재생에너지학회 학술대회논문집 Vol.2021 No.7
Bifacial silicon heterojunction (SHJ) solar cells have been attracted due to potential high performance. Because of bifacial illumination, wide-gap hydrogenated nano-crystalline silicon oxide (nc-SiOx:H) materials should be used as front and back surface filed to enhancing significantly the light into the absorber. In this work, we reduced the band-offset at the p/i interface of bifacial SHJ cells using buffer layers. With ultra-thin hydrogenated amorphous silicon oxide (a-SiOx:H) buffer layer, the band-offset at the p/i interface was significantly decreased resulting in effective hole carrier collection. A considerable enhancement in the open-circuit voltage (Voc) and fill factor (FF) was obtained. These were confirmed by experiment and simulation results. An experiment high efficiency of 23% at one side illumination with Voc of 729 mV, FF of 80% and short-circuit current density of 39.5 mA/cm<sup>2</sup> was obtained.
Pham, Duy Phong,Kim, Sangho,Park, Jinjoo,Le, Anh Huy Tuan,Cho, Jaehyun,Yi, Junsin ELSEVIER SCIENCE 2017 JOURNAL OF ALLOYS AND COMPOUNDS Vol.724 No.-
<P><B>Abstract</B></P> <P>We examined different buffer layers at the i/n interface of narrow-gap amorphous silicon germanium alloy (a-SiGe:H)-based thin-film solar cells. These buffers included a conventional hydrogenated amorphous silicon (a-Si:H), an inversely graded hydrogenated amorphous silicon germanium, and a crystalline seed buffer (CSB). The solar cell with the CSB shows the highest performance, of 10%. The better carrier extraction at the rear side of the device is attributed to the role of the CSB layer. The effect of CSB thickness from 50 nm to 100 nm on cell performance was examined. Cell efficiency increased with the buffer thickness up to 80 nm and decreased with buffer thickness of 100 nm. This decrease can be attributed to increased defect densities of the buffer due to less efficient passivation of amorphous phase at the crystalline column boundaries.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Carrier extraction at the i/n interface is improved by crystalline seed buffer (CSB) layer. </LI> <LI> Role of crystalline seed buffer layer is discussed in detail. </LI> <LI> High efficiency of 10% of graded a-SiGe:H thin film solar cell is obtained with CSB buffer. </LI> </UL> </P>
Potential Wide-gap Materials as a Top Cell for Multi-junction c-Si Based Solar Cells: A Short Review
Duy Phong Pham,이선화,김세현,오동현,Muhammad Quddamah Khokhar,김상호,박진주,김영국,조은철,조영현,이준신 한국태양광발전학회 2019 Current Photovoltaic Research Vol.7 No.3
Silicon heterojunction solar cells (SHJ) have dominated the photovoltaic market up till now but their conversion performance is practically limited to around 26% compared with the theoretical efficiency limit of 29.4%. A silicon based multi-junction devices are expected to overcome this limitation. In this report, we briefly review the state-of-art characteristic of wide-gap materials which has played a role as top sub-cells in silicon based multi-junction solar cells. In addition, we indicate significantly practical challenges and key issues of these multi-junction combination. Finally, we focus to some characteristics of III-V/c-Si tandem configuration which are reaching highly record performance in multi-junction silicon solar cells.
Boron-doped hydrogenated mixed-phase silicon as thermo-sensing films for infrared detectors
Phong Pham, Duy,Park, Jinjoo,Shin, Chonghoon,Kim, Sangho,Nam, Yonghyun,Kim, Geunho,Kim, Minsik,Yi, Junsin Elsevier 2018 Materials science in semiconductor processing Vol.74 No.-
<P><B>Abstract</B></P> <P>Silicon materials have been widely used as thermo-sensing layers in infrared detectors or uncooled micro-bolometers. Parameters such as a large thermal coefficient of resistance (TCR), low sheet resistance (R<SUB>s</SUB>), and low 1/f noise are important for high performance of these devices. However, there is always a trade-off between these parameters. For example, the crystalline silicon materials typically exhibit low R<SUB>s</SUB> and 1/f noise, and significantly low TCR, while the amorphous silicon materials generally have large TCR, and considerably high R<SUB>s</SUB> and 1/f noise. Consequently, the best trade-off can be achieved by using a mixed-phase structure of silicon materials, i.e. an intermediate form between the crystalline and amorphous structures. Herein we report the important characteristics of hydrogenated mixed-phase silicon films, deposited by the plasma-enhanced chemical vapour deposition process, for infrared detectors. The films in the mixed-phase structure showed high TCR values in the range of 2–3%K<SUP>–1</SUP> and moderate sheet resistances in range of 10–40MΩsq<SUP>−1</SUP>. These results indicate that the mixed-phase silicon films are potential alternatives to conventional boron doped hydrogenated amorphous and microcrystalline silicon films for use as thermo-sensing layers in infrared detectors.</P>
Pham, Duy Phong,Kim, Sangho,Lee, Sunhwa,Le, Anh Huy Tuan,Cho, Eun-Chel,Park, Jinjoo,Yi, Junsin Elsevier 2019 Infrared physics & technology Vol.102 No.-
<P><B>Abstract</B></P> <P>Remarkable progress has been made in the improvement of rear-emitter silicon heterojunction (RE-SHJ) solar cells with the use of very thin n-type front contact layers. However, further reducing the thickness of the front window layers while maintaining high conductivity for mitigating the parasitic absorption and carrier collection loss has proven challenging. In this study, we implement controlling a seed layer for achieving ultra-thin, high crystalline and conductivity of n-type hydrogenated microcrystalline silicon oxide (n-µc-SiO<SUB>x</SUB>:H) front window layer in RE-SHJ solar cells. By using a seed layer, the crystallinity confirmed by Raman and TEM measurements, and the conductivity of the n-µc-SiO<SUB>x</SUB>:H front layers are significantly enhanced compared with that without using the seed layer. This leads to a remarkable increase in the open-circuit voltage (<I>V</I> <SUB>oc</SUB>) by 6 mV and fill factor (<I>FF</I>) by 4.11% while maintaining a high short-circuit current density (<I>J</I> <SUB>sc</SUB>) in range of 38 mA/cm<SUP>2</SUP>. A high cell performance of 21.1% is obtained with the use of an optimised seed layer.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Effect of deposition power densities on seed-growth via TEM measurement was discussed. </LI> <LI> High crystallinity and conductivity of ultra-thin n-µc-SiOx:H front layer for RE-SHJ solar cells. </LI> <LI> V<SUB>oc</SUB> enhancement by 6 mV and fill factor by 4.11% due to optimization of seed layer. </LI> </UL> </P>