To further increase the conversion efficiency of crystalline silicon (c-Si) solar cells, it is vital to reduce recombination losses associated with contacts. Therefore, a contact structure that simultaneously passivates c-Si surface while selectively extracting only one type charge carrier (i.e., either electrons or holes) desired. Realizing such passivating contacts in cells has become an important research objective, and overview classification work date on this topic presented here. Using...

The interplay between hydrogenation and passivation of poly-Si/SiOx contacts to n-type Si wafers is studied using atomic layer deposited Al2O3 anneals in forming gas nitrogen. stacks are prepared by thermal oxidation followed crystallization a-Si:H films plasma-enhanced chemical vapor deposition. Implied open-circuit voltages as high 710 mV achieved for p-type after hydrogenation. Correlating minority carrier lifetime data secondary ion mass spectrometry profiles reveals that the main...

Passivating contacts based on metal oxides have proven to enable high energy conversion efficiencies for crystalline silicon (c-Si) solar cells at low processing complexity. In this work, the potential of atomic-layer deposited (ALD) Nb2O5 as novel electron-selective passivating contact is explored in terms recombination parameter J0 and resistivity ρc. It shown that after forming gas annealing, ALD can provide adequate surface passivation with values down 25–30 fA/cm2. On HF-treated c-Si...

In this work, the structural, electrical, and optical properties as well chemical bonding state of Al-doped ZnO films deposited by atomic layer deposition have been investigated to obtain insight into doping electrical transport mechanisms in films. The range levels from 0% 16.4% Al was accomplished tuning ratio Al2O3 ALD cycles. With X-ray photoelectron spectroscopy depth profiling transmission electron microscopy, we could distinguish individual AlOx layers For with a thickness 40 nm,...

We present a detailed material study of n+-type polysilicon (polySi) and its application as carrier selective rear contact in bifacial n-type solar cell comprising fire-through screen-printed metallization 6" Cz wafers. The cells were manufactured with low-cost industrial process steps yielding Vocs from 676 to 683 mV Jscs above 39.4 mA/cm2 indicating an efficiency potential 22%. aim this is understand which properties determine the performance POCl3-diffused (n-type) polySi-based...

Despite the existence of several highly effective and well-characterized passivating materials for crystalline silicon surfaces, topic surface passivation investigation new remain considerable interest photovoltaics research. However, question whether under what circumstances a particular material will provide remains difficult to answer. In this work, we an overview recent insights relating question, drawing from our own work on novel including MoOx, Nb2O5, TiOx, ZnO, POx, illustrated with...

Doped polycrystalline silicon (poly-Si), when coupled with a thin SiO2 interlayer, is of large interest for crystalline (c-Si) solar cells due to its outstanding passivating contact properties. To reach high levels surface passivation, it pivotal hydrogenate the poly-Si and underlying c-Si/SiO2 interface. This can be done by capping hydrogen-containing dielectric layer such as Al2O3 or SiNx, followed thermal anneal. On basis recent research, this work addresses several aspects hydrogenation...

Surface passivation is essential for high-efficiency crystalline silicon (c-Si) solar cells. Despite the common use of transparent conductive oxides (TCOs) in field cells, obtaining surface by TCOs has thus far proven to be particularly challenging. In this work, we demonstrate outstanding c-Si surfaces highly ZnO films prepared atomic layer deposition. Effective recombination velocities as low 4.8 cm/s and 11 are obtained on 3 Ω cm n- p-type (100) c-Si, respectively. The high levels...

Stacks consisting of an ultrathin SiO2 coated with atomic-layer deposited (ALD) zinc oxide (ZnO) and aluminum (Al2O3) have been shown to yield state-of-the-art passivation n-type crystalline silicon surfaces. The distinguishing aspect this novel stack is the very conductive nature passivating ZnO layer. In work, it demonstrated that such a can provide additional functionalities relevant for solar cells. Specifically, transparent stacks passivate textured n+-diffused surfaces they form Ohmic...

In this work, an optical modeling study on electron scattering mechanisms in plasma-deposited ZnO layers is presented. Because various applications of films pose a limit the carrier density due to its effect film transmittance, higher mobility values are generally preferred instead. Hence, insights into contributions affecting required. models, Drude oscillator adopted represent free-electron contribution and obtained can be then correlated with macroscopic material properties. However,...

This letter reports on effective surface passivation of n-type crystalline silicon by ultrathin niobium oxide (Nb2O5) films prepared atomic layer deposition (ALD) and subjected to a forming gas anneal at 300 °C. A champion recombination parameter J0 20 fA/cm2 velocity Seff 4.8 cm/s have been achieved for 1 nm. The pretreatment was found strong impact the passivation. Good can be both HF-treated c-Si surfaces with wet-chemically grown interfacial layer. On surfaces, minimum film thickness 3...

To further increase the conversion efficiency of crystalline silicon solar cells it is vital to reduce recombination losses between photoactive part cell and metal contacts. This ideally achieved by fabricating contacts which passivate defects at surface while being simultaneously selective for only a single type charge carrier, i.e. either electrons or holes. Despite extensive research effort aimed realizing such contacts, no clear overview fundamental physics passivating has appeared yet....

Recently, stacks consisting of an ultrathin SiO2 coated with atomic-layer-deposited (ALD) Al-doped zinc oxide (ZnO:Al) have been shown to yield state-of-the-art passivation n-type crystalline silicon surfaces and provide low contact resistivities n+-doped Si poly-Si surfaces. Key for achieving good surface are intentionally-grown interlayer, aluminum (Al2O3) capping layer a post-deposition anneal, whereas doping the ZnO is required achieve resistivity. In this work, we present latest results...

Black silicon (b-Si) nanotextures can significantly enhance the light absorption of crystalline solar cells. Nevertheless, for a successful application b-Si textures in industrially relevant cell architectures, it is imperative that charge-carrier recombination at particularly highly n-type doped black Si surfaces further suppressed. In this work, issue addressed through systematically studying lowly and surfaces, which are passivated by atomic-layer-deposited Al2O3 films or SiO2/Al2O3...

Interdigitated back-contact (IBC) solar cells based on diffused crystalline silicon comprise a series of pn-junctions which border at the rear surface wafer. In this work, it is established that presence these can induce significant additional charge-carrier recombination, affect conversion efficiency IBC through reduction in fill factor and open-circuit voltage. Using specialized test structures with varying length per area cell (i.e., junction density), magnitude recombination pn-junction...

A p <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> -doping method for silicon solar cells is presented whereby boron atoms from a pure (PureB) layer deposited by chemical vapor deposition using B <sub xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> H xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> as precursor were thermally diffused into silicon. The applicability of this doping process the doped surfaces was evaluated in terms...

The interaction between O2 and ZnO thin films prepared by atomic layer deposition has been investigated time-dependent second-harmonic generation, probing the electric field induced adsorbed oxygen molecules on surface. generated signal decays upon laser exposure due to two-photon assisted desorption of O2. Blocking unblocking beam for different time intervals reveals adsorption rate onto ZnO. results demonstrate that generation provides a versatile non-contact probe kinetics films.

A review of recent developments in the field passivation c-Si surfaces is presented, with a particular focus on materials that can be prepared by atomic layer deposition (ALD). Besides Al <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> O xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> , various other novel schemes have recently been developed, such as Ga Ta xmlns:xlink="http://www.w3.org/1999/xlink">5</inf> SiO /Al HfO and TiO which...

In the field of photovoltaics, atomic layer deposition (ALD) is mostly known for its success in preparing Al <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> O xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> -based surface passivation layers c-Si homojunction cells. last years, many novel types heterojunctions have appeared, referred to as passivating contacts. these concepts, metal oxide thin films are used passivation, carrier...