Transparent Conductive AGZO/Ag/AGZO Multilayers on PET Substrate by Roll-to-Roll Sputtering

Area of Science:

• Materials Science
• Thin Film Technology
• Optoelectronics

Background:

• Transparent conductive films (TCFs) are crucial for optoelectronic devices.
• Traditional TCFs often rely on indium-tin oxide (ITO), facing cost and scarcity issues.
• Developing indium-free TCFs is essential for sustainable technological advancement.

Purpose of the Study:

• To investigate the fabrication of indium-free Al and Ga-codoped ZnO (AGZO)/Ag/AGZO multilayer films using large-scale roll-to-roll sputtering.
• To optimize the film thicknesses by adjusting roll speeds for enhanced optical and electrical properties.
• To analyze the impact of the nanoscale silver interlayer on the performance of AGZO multilayer films.

Main Methods:

• Dual target roll-to-roll radio frequency (RF) sputtering for AGZO deposition.
• DC sputtering for the silver (Ag) interlayer deposition at room temperature.
• Optimization of AGZO/Ag/AGZO multilayer thicknesses by varying roll speeds (0.15/1.1/0.15 m/min).
• Characterization of optical transparency and electrical sheet resistance on polyethylene terephthalate (PET) substrates.

Main Results:

• Achieved excellent optical transparency of 84% at 550 nm for the optimized AGZO/Ag/AGZO multilayer films.
• Obtained a low sheet resistance of 9.2 omega/sq. on PET substrates.
• Demonstrated the feasibility of large-scale, room-temperature deposition of indium-free TCFs.
• Identified optimal thicknesses for AGZO/Ag/AGZO layers as 9.21 nm, 8.32 nm, and 8.04 nm, respectively.

Conclusions:

• Indium-free AGZO/Ag/AGZO multilayer films are successfully fabricated using scalable roll-to-roll sputtering.
• The nanoscale silver interlayer significantly enhances the electrical and optical properties of the films.
• These optimized films show great potential as cost-effective alternatives to ITO for various optoelectronic applications.