Process-Induced Degradation of SiO&lt;inline-formula&gt;&lt;tex-math&gt;$_{\bf 2}$&lt;/tex-math&gt;&lt;/inline-formula&gt; and a-Si:H Passivation Layers for Photovoltaic Applications

O’Sullivan, Barry; Bearda, Twan; Nadupalli, Shankari; Labie, Riet; Baert, Kris; Gordon, Ivan; Poortmans, Jef

doi:10.1109/jphotov.2014.2326711

Cited by 9 publications

(2 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This finding has been confirmed in other work by capacitance-voltage analysis techniques. 18 It confirms e-beam passivation degradation by Si dangling bond defects at the c-Si/a-Si interface and in the a-Si (bulk) passivation layer while this is not observed for thermal evaporation. The surface state defects density Q SS leads to an increase of the ideal barrier height by Eq.…”

Section: Variations In Metallization Type and Methodsmentioning

confidence: 55%

Resistance and passivation of metal contacts using n-type amorphous Si for Si solar cells

Labie

Bearda

Daïf

et al. 2014

Journal of Applied Physics

View full text Add to dashboard Cite

A low fill factor remains one of the critical issues for successful implementation of amorphous Si layers in back-contact solar cells. In this work, the metal-phosphorous doped hydrogenated amorphous silicon (a-Si:H) contact is studied in terms of contact resistance while maintaining a high passivation level of the crystalline silicon bulk material after metal deposition and during long-term solar cell operation. On top of these contacting and passivation-preservation requirements, the metal back-surface reflection has to be large in order to reflect as much light as possible to generate high output current densities. Two different contact metals, Al and Ti, with Ti being combined in a stack with either Al, Pd/Ag or Cu, are investigated. For these two metals with comparable metal work function, the material choice shows only a minimal effect on the contact resistance value. The main parameters for obtaining a low-resistive, ohmic contact lie in the tuning of the n+ a-Si:H layer thickness and the application of a thermal annealing step. Contact resistance values down to 10 mΩ cm2 are obtained on an intrinsic/n+ a-Si:H layer stack with a remaining effective lifetime of several milliseconds after metallization and anneal. It is shown that a thin Ti (5 nm) layer is needed in order to obtain a thermally stable contact that guarantees a reliable long-term solar cell operation. The optical disadvantage of having Ti at the backside of a Si solar cell can be compensated by combining this very thin Ti layer with Cu. This results in an improvement of the back-reflectance compared to a direct Al contact.

show abstract

Section: Variations In Metallization Type and Methodsmentioning

confidence: 55%

Resistance and passivation of metal contacts using n-type amorphous Si for Si solar cells

Labie

Bearda

Daïf

et al. 2014

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

“…S6). The second issue is that without TCO as buffer layer, fabricating metals directly on a-Si:H stacks causes a degradation on the passivation of the solar cell 20 . The metal/a-Si:H contact was investigated by performing scanning transmission electron microscopy (STEM) on the metal/a-Si:H interface.…”

Section: Direct Metal/a-si:h Contactsmentioning

confidence: 99%

Transparent-conductive-oxide-free front contacts for high-efficiency silicon heterojunction solar cells

Pomaska

Lambertz

et al. 2021

Joule

View full text Add to dashboard Cite

In order to compensate the insufficient conductance of heterojunction thin films, transparent conductive oxides (TCO) have been used for decades in both-sides contacted crystalline silicon heterojunction (SHJ) solar cells to provide lateral conduction for efficient carrier collection. In this work, we substitute the TCO layers by utilizing the lateral conduction of c-Si absorber, thereby enabling a TCO-free design. A series resistance of 0.32 Ωcm 2 and a fill factor of 80.7% were measured for a TCO-free back-junction SHJ solar cell with a conventional finger pitch of 1.8 mm, thereby proving that relying on lateral conduction in the c-Si bulk is compatible with low series resistances. Achieving high efficiencies in SHJ solar cells with TCO-free front contacts requires suppressing deterioration of the passivation quality induced by direct metal-a-Si:H contacts and in-diffusion of metal into the a-Si:H layer. We show that an ozone treatment at the a-Si:H/metal interface suppresses the metal diffusion and improves the passivation without increasing the

show abstract

Process-induced losses by plasma leakage in lithography-free shadow masked interdigitated back contact silicon heterojunction architectures

Soman

Das

Ahmed

et al. 2023

Materials Science in Semiconductor Processing

View full text Add to dashboard Cite

Process-Induced Degradation of SiO<inline-formula><tex-math>$_{\bf 2}$</tex-math></inline-formula> and a-Si:H Passivation Layers for Photovoltaic Applications

Cited by 9 publications

References 14 publications

Resistance and passivation of metal contacts using n-type amorphous Si for Si solar cells

Resistance and passivation of metal contacts using n-type amorphous Si for Si solar cells

Transparent-conductive-oxide-free front contacts for high-efficiency silicon heterojunction solar cells

Process-induced losses by plasma leakage in lithography-free shadow masked interdigitated back contact silicon heterojunction architectures

Contact Info

Product

Resources

About