Hole-Collection Mechanism in Passivating Metal-Oxide Contacts on Si Solar Cells: Insights From Numerical Simulations

Vijayan, Ramachandran Ammapet; Essig, Stephanie; Wolf, Stefaan De; Ramanathan, Bairava Ganesh; Löper, P.; Ballif, Christophe; Varadharajaperumal, Muthubalan

doi:10.1109/jphotov.2018.2796131

Cited by 82 publications

(57 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In a conventional PN junction, the built-in potential is considered the internal force to separate the photogenerated carriers. However, current research suggests that the PN junction is not necessary for a solar cell, while the asymmetric conductivity of the contact layers on the two sides of the absorber layer is the internal force that promotes the separation of photogenerated carriers [86,87]. As a new type of solar cell, which has just been developed in recent years, the basic physical principles of the internal force of carrier separation in c-Si DASH solar cells have not been clearly understood [60,61], even though their conversion efficiencies are higher than 20% [40].…”

Section: Carrier Separationmentioning

confidence: 99%

See 1 more Smart Citation

Recent Advances in and New Perspectives on Crystalline Silicon Solar Cells with Carrier-Selective Passivation Contacts

Yao

et al. 2018

Crystals

View full text Add to dashboard Cite

Crystalline silicon (c-Si) is the dominating photovoltaic technology today, with a global market share of about 90%. Therefore, it is crucial for further improving the performance of c-Si solar cells and reducing their cost. Since 2014, continuous breakthroughs have been achieved in the conversion efficiencies of c-Si solar cells, with a current record of 26.6%. The great efficiency boosts originate not only from the materials, including Si wafers, emitters, passivation layers, and other functional thin films, but also from novel device structures and an understanding of the physics of solar cells. Among these achievements, the carrier-selective passivation contacts are undoubtedly crucial. Current carrier-selective passivation contacts can be realized either by silicon-based thin films or by elemental and/or compound thin films with extreme work functions. The current research and development status, as well as the future trends of these passivation contact materials, structures, and corresponding high-efficiency c-Si solar cells will be summarized.

show abstract

Section: Carrier Separationmentioning

confidence: 99%

“…Vijayan [87] and Messmer [88] studied the hole transport paths at the TMO/Si interface by simulations. They held similar ideas that there are two possible paths, including band-to-band tunneling (B2B) and defect-assisted tunneling (TAT), depending on the electron affinity of TMO.…”

Section: Carrier Transportmentioning

confidence: 99%

Recent Advances in and New Perspectives on Crystalline Silicon Solar Cells with Carrier-Selective Passivation Contacts

Yao

et al. 2018

Crystals

View full text Add to dashboard Cite

show abstract

“…As a consequence, efficient carrier extraction requires that photogenerated holes in the valence band of c‐Si recombine with electrons present in the MoO X conduction band; the latter electrons are injected from the degenerately n‐type doped TCO . Efficient charge‐carrier transport through this contact stack depends on the thickness, defect density (for trap‐assisted transport) and work function of MoO X , as well as on the line‐up with the band edge energies of the surrounding layers.…”

Section: Introductionmentioning

confidence: 99%

Toward Annealing‐Stable Molybdenum‐Oxide‐Based Hole‐Selective Contacts For Silicon Photovoltaics

et al. 2018

Self Cite

View full text Add to dashboard Cite

This is the pre-peer reviewed version of the following article: "Towards annealing-stable molybdenum-oxide-based hole-selective contacts for silicon photovoltaics", which has been published in final form at https://DOI. Sandwiched between a hydrogenated intrinsic amorphous silicon passivation layer and a transparent conductive oxide, this material allows a highly efficient hole-selective front contact stack for crystalline silicon solar cells. However, hole extraction from the Si wafer and transport through this stack degrades upon annealing at 190 °C, which is needed to cure the screen-printed Ag metallization applied to typical Si solar cells. Here, we show that effusion of hydrogen from the adjacent layers is a likely cause for this degradation, highlighting the need for hydrogen-lean passivation layers when using such metal-oxidebased carrier-selective contacts. Pre-MoOX-deposition annealing of the passivating a-Si:H layer is shown to be a straightforward approach to manufacturing MoOX-based devices with high fill factors using screen-printed metallization cured at 190 °C.a Electronic mail: Mathieu.boccard@epfl.ch

show abstract

Section: Resultsmentioning

confidence: 99%

“…Inspired by the great potential of the SHJ solar cells with a MoO x HSL, a lot of researches, numerically or experimentally, on the current extraction of charge carriers via the MoO x HSL were conducted to deeply understand the transport mechanisms and to assist the engineering of the novel SHJ solar cells . It was shown that, for an effective hole extraction, a sufﬁciently high MoO x work function or/and efﬁcient trap‐assisted tunneling paths are requirements that have to be fulﬁlled . Based on the analysis of the dark J–V–T characteristics, transport mechanisms including trap‐assisted tunnel of holes at low voltage and transport behavior of a Schottky‐like junction at higher voltage were proposed by García‐Hernansanza et al for a SHJ solar cell with a thermally evaporated MoO x HSL and without any passivation layer .…”

Section: Resultsmentioning

confidence: 99%

Silicon Heterojunction Solar Cells with MoO_x Hole‐Selective Layer by Hot Wire Oxidation–Sublimation Deposition

Zhou

Yang

et al. 2020

Solar RRL

View full text Add to dashboard Cite

In this article, a novel hot wire oxidation–sublimation deposition (HWOSD) technique, as an optional technology, is developed to prepare molybdenum oxide (MoOx) thin films. Silicon heterojunction (SHJ) solar cells with the HWOSD MoOx as a hole‐selective transport layer (HSL) are fabricated. A power conversion efficiency up to 21.10% is achieved on a champion SHJ solar cell using a 14 nm MoOx layer as the HSL. Dark current density–voltage–temperature (J–V–T) characteristics of the SHJ solar cell are measured at temperatures ranging from 200 to 380 K. Transport processes including thermionic emission of electrons over the potential barrier and quantum‐assisted tunneling of holes through the gap states in the MoOx layer are used to fit the J–V curves of the MoOx/n‐c‐Si heterojunction. The investigation of the transport mechanisms provides a better understanding of the characteristics of the novel SHJ solar cells and it is helpful to fully demonstrate the potential of such kinds of solar cells in the future.

show abstract

Hole-Collection Mechanism in Passivating Metal-Oxide Contacts on Si Solar Cells: Insights From Numerical Simulations

Cited by 82 publications

References 38 publications

Recent Advances in and New Perspectives on Crystalline Silicon Solar Cells with Carrier-Selective Passivation Contacts

Recent Advances in and New Perspectives on Crystalline Silicon Solar Cells with Carrier-Selective Passivation Contacts

Toward Annealing‐Stable Molybdenum‐Oxide‐Based Hole‐Selective Contacts For Silicon Photovoltaics

Silicon Heterojunction Solar Cells with MoO_x Hole‐Selective Layer by Hot Wire Oxidation–Sublimation Deposition

Contact Info

Product

Resources

About

Hole-Collection Mechanism in Passivating Metal-Oxide Contacts on Si Solar Cells: Insights From Numerical Simulations

Cited by 82 publications

References 38 publications

Recent Advances in and New Perspectives on Crystalline Silicon Solar Cells with Carrier-Selective Passivation Contacts

Recent Advances in and New Perspectives on Crystalline Silicon Solar Cells with Carrier-Selective Passivation Contacts

Toward Annealing‐Stable Molybdenum‐Oxide‐Based Hole‐Selective Contacts For Silicon Photovoltaics

Silicon Heterojunction Solar Cells with MoOx Hole‐Selective Layer by Hot Wire Oxidation–Sublimation Deposition

Contact Info

Product

Resources

About

Silicon Heterojunction Solar Cells with MoO_x Hole‐Selective Layer by Hot Wire Oxidation–Sublimation Deposition