Role of O2 radicals on silicone plasma treatments for a‐Si:H surface passivation of PV wafers bonded to glass. Issue 9 (7th April 2015)

• Record Type: Journal Article
• Authors: Granata, Stefano Nicola; Marchegiani, Alessio; Bearda, Twan; Tous, Loic; Cheyns, David; Abdulraheem, Yaser; Gordon, Ivan; Szlufcik, Jozef; Mertens, Robert; Poortmans, Jef
• Is Part Of: Physica status solidi. Volume 212:Issue 9(2015:Sep.)
• Page Start: 1946
• Page End: 1953
• Publication Date: 2015-04-07
• Subjects: amorphous silicon -- plasma treatment -- polydimethylsiloxane -- surface passivation; Solid state physics -- Periodicals; Solids -- Industrial applications -- Periodicals; 530.41
• DOI: 10.1002/pssa.201431945
• Languages: English
• ISSNs: 1862-6300

Abstract

Abstract : Argon (Ar) and oxygen (O2 ) plasmas are performed on silicone adhesives to eliminate the negative influence of silicone on amorphous silicon (a‐Si:H) surface passivation of wafers bonded to glass. Both the Ar and O2 plasmas lead to oxidation of the silicone surface, consisting in an increase of oxygen/carbon ratio, of degree of crosslinking, and of material density. The oxidized silicone is more resilient than pristine and does not interact with the a‐Si:H passivation process, allowing for state‐of‐the‐art surface passivation of wafers bonded to glass. Similarities between the modifications induced by the Ar and O2 plasmas on the silicone indicate the secondary role of the O2 radicals in the oxidation process. Moreover, amorphous/crystalline heterojunction interdigitated back contact solar cells (a‐Si:H/c‐Si HJ i‐BC) are fabricated on freestanding and bonded wafers treated with Ar plasma. The devices show comparable open‐circuit voltages of up to 675 mV, confirming at device level the efficacy of the treatment.