Surface Modification of Backsheets Using Coupling Agents for Roll-To-Roll Processed Thin-Film Solar Photovoltaic (PV)...

Area of Science:

• Materials Science
• Surface Engineering
• Flexible Electronics

Background:

• Moisture stability is crucial for flexible electronic and photonic devices.
• Hermetic sealing is difficult; impeding moisture ingress is a practical alternative.
• Interfacial adhesion strength is critical for outdoor optoelectronic devices like solar cells.

Purpose of the Study:

• To improve the adhesion between poly(ethylene terephthalate) (PET) carrier films and thermoset encapsulant polymers.
• To evaluate the effectiveness of different surface modification techniques (chemical, UV/ozone, combined) on adhesion.
• To assess the durability of enhanced adhesion under damp-heat environmental conditions.

Main Methods:

• Surface modification of PET films using chemical treatments.
• Surface modification of PET films using UV/ozone treatments.
• Combined chemical and UV/ozone treatments for PET film surface modification.
• Adhesion strength testing before and after damp-heat exposure (60 °C, 90% RH).

Main Results:

• Surface treatments increased wettability and adhesion strength.
• The combined chemical and UV/ozone treatment yielded the highest adhesion improvement.
• Adhesion increased up to 12.1-fold with the combined treatment.
• A 200% increase in adhesion strength was observed even after severe damp-heat exposure.

Conclusions:

• Combined surface modification is highly effective for enhancing PET-encapsulant adhesion.
• The improved adhesion demonstrates significant moisture barrier properties for flexible devices.
• This approach offers a practical solution for durable outdoor optoelectronic applications.