Plasma Surface Modification of Polymer Backsheets: Origins of Future Interfacial Barrier/Backsheet Failure (Poster)

Conference · Mon May 01 00:00:00 EDT 2006

DOI:https://doi.org/10.1109/WCPEC.2006.279620· OSTI ID:893118

Pankow, J W; Glick, S H

Flexible polymer substrates coated with inorganic oxide moisture barriers are a potential replacement for glass backsheets in thin-film PV (photovoltaic) modules. Silicon oxynitride (SiO{sub x}N{sub y}) deposited by plasma enhanced chemical vapor deposition (PECVD) on polyethylene terephthalate (PET) represents one potential new backsheet candidate. Barrier deposition runs at NREL have included a nitrogen-rich plasma pretreatment prior to barrier deposition with the intention of cleaning the PET surface and enhancing adhesion of the SiO{sub x}N{sub y} barrier film to PET; however, test coupons of PET/barrier/EVA/TPE failed after damp-heat exposure. (EVA is ethylene vinyl acetate and TPE is Tedlar{reg_sign}-PET-EVA). PET substrates exposed to plasma conditions similar to those used in pretreatment were examined by X-ray photoelectron spectroscopy (XPS) to reveal that new low molecular weight PET fragments were created at the PET surface. These fragments are responsible for barrier/PET interfacial failure and barrier transfer to the EVA encapsulant side following damp heat exposure.

• Research Organization: National Renewable Energy Lab. (NREL), Golden, CO (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC36-99-GO10337
• OSTI ID: 893118
• Report Number(s): NREL/PO-520-39954; TRN: US200625%%97
• Resource Relation: Conference: Prepared for the 2006 IEEE 4th World Conference on Photovoltaic Energy Conversion (WCPEC-4), 7-12 May 2006, Waikoloa, Hawaii
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
36 MATERIALS SCIENCE
ADHESION
CHEMICAL VAPOR DEPOSITION
CLEANING
DEPOSITION
ENERGY CONVERSION
ETHYLENE
GLASS
MODIFICATIONS
MOISTURE
MOLECULAR WEIGHT
OXIDES
POLYETHYLENES
POLYMERS
POLYVINYLS
SILICON
SUBSTRATES
X-RAY PHOTOELECTRON SPECTROSCOPY
POLYMER SUBSTRATES
PLASMA
PET
INORGANIC OXIDE MOISTURE BARRIERS
GLASS BACKSHEETS
THIN-FILM
PV
PHOTOVOLTAIC
Solar Energy - Photovoltaics