Strategies for realizing high-efficiency silicon heterojunction solar cells

Silicon heterojunction (SHJ) solar cells have achieved a record efficiency of 26.81% in a front/back-contacted (FBC) configuration. Moreover, thanks to their advantageous high V_OC and good infrared response, SHJ solar cells can be further combined with wide bandgap perovskite cells forming tandem devices to enable efficiencies well...

The optical performance of random and periodic textured mono crystalline silicon surfaces for photovoltaic applications

Surface textures that result in high optical yields are crucial for high efficiency photovoltaic (PV) devices. In this work three different texturing approaches are presented that result in smooth concave structures devoid of sharp features. Such features can sustain the crack-free growth of device quality nano- to poly-crystalline materials...

PECVD Processing of low bandgap-energy amorphous hydrogenated germanium-tin (a-GeSn:H) films for opto-electronic applications

An alloy based on the group IV elements germanium and tin has the potential of yielding an earth-abundant low bandgap energy semiconductor material with applications in the fields of micro-electronics, optics, photonics and photovoltaics. In this work, the first steps towards the plasma enhanced chemical vapour deposition (PECVD) processing of a...

Device operation of P-ion-implanted n-BaSi₂/p-Si heterojunction solar cells

We formed phosphorous(P)-ion-implanted n-BaSi₂ films on p-Si(111) substrates and demonstrated solar-cell functionality of the n-BaSi₂/p-Si heterojunction under AM1.5 illumination. The BaSi₂ films were grown by molecular beam epitaxy, followed by implantation of P ions to the BaSi₂ films using PF<sub...

Passivation Enhancement of Poly-Si Carrier-Selective Contacts by Applying ALD Al_2O_3 Capping Layers

Hydrogenation of polycrystalline silicon (poly-Si) passivating contacts is crucial for maximizing their passivation performance. This work presents the application of Al2O3 prepared by atomic layer deposition as a hydrogenating capping layer. Several important questions related to this application of Al2O3 are addressed by comparing results...

Implantation-based passivating contacts for crystalline silicon front/rear contacted solar cells

In this work, we develop SiO_x/poly-Si carrier-selective contacts grown by low-pressure chemical vapor deposition and boron or phosphorus doped by ion implantation. We investigate their passivation properties on symmetric structures while varying the thickness of poly-Si in a wide range (20-250 nm). Dose and energy of implantation...

Modulated surface texturing of temporary Al foils substrates for high-efficiency thin-film, flexible solar cells

In this work we focus on texturing Al substrate in order to employ the modulated surface texturing approach for thin-film, flexible, micromorph solar cells. We deployed two different methods to induce micro-craters in Al foil, i) bare Al etching by KOH and ii) AZO sacrificial layer etched in KOH. After modelling the etching kinetics of KOH on...

Strategies for the implementation of ion implantation doping technique in c-Si wafer-based solar cells

Electricity consumption is increased in last twenty years. It is crucial therefore to find alternative, renewable and sustainable sources to mantain this development. Solar energy has proved to be a valid alternative to produce clean energy. The gigantic development of solar energy technology in the last twenty years has lead to a scenario...

High temperature oxidation pre-treatment of textured c-Si wafers passivated by a-Si:H

This work shows an alternative surface cleaning method for c-Si wafers to replace the standard chemical procedures as RCA or HNO ₃ which involve hazardous chemicals or unstable processes. The method consists in a high-temperature oxidation treatment (HTO) performed in a classical tube furnace that incorporates organic and metal...

Front and rear contact Si solar cells combining high and low thermal budget Si passivating contacts

In this work we develop a rear emitter silicon solar cell integrating carrier-selective passivating contacts (CSPCs) with different thermal budget in the same device. The solar cell consists of a B-doped poly-Si/SiO_x hole collector and an i/n hydrogenated amorphous silicon (a-Si:H) stack acting as electron collector placed on the...

High-efficiency black IBC c-Si solar cells with poly-Si as carrier-selective passivating contacts

In this work, we present the application of poly-Si carrier-selective passivating contacts (CSPCs) as both polarities in interdigitated back-contacted (IBC) solar cell architectures. We compared two approaches to form a gap between the back-surface field (BSF) and emitter fingers. It is proved that the gaps prepared by both approaches are...