Stabilizing ultrathin Silver (Ag) films on different substrates

TL;DR

This study introduces a method to stabilize ultrathin silver films on various substrates using zinc filler metal, enhancing their adhesion, stability, and optical properties for optoelectronic applications.

Contribution

The paper presents a novel zinc-based technique to improve adhesion, stability, and performance of ultrathin silver films on multiple substrates.

Findings

Ultrathin Ag films achieved low sheet resistance (~3 Ω/Sq)

Films exhibit low surface roughness (~1 nm)

Enhanced stability and optical transparency (~65%)

Abstract

This paper reports an effective method of stabilizing ultrathin Silver (Ag) films on substrates using a filler metal (Zn). Ag films with a thickness < 15 nm were deposited by DC magnetron sputtering above a Zn filler metal on glass, quartz, silicon and PET (polyethylene terephthalate) substrates. Zinc is expected to partially or fully fill the roughness associated with the substrates. The Zn filler material and ultrathin Ag film form a 3-D augmented atomically chemically graded interface. 3-D interfaces have smoothly varying chemistry. The ability of Zn to partially or fully fill the substrate roughness improves the adhesion of Zn along with the Ag to the substrate. Also, Zn acts as a barrier layer against the diffusion of Ag into the substrate. This technique leads to ultrathin Ag films with low sheet resistance (~ 3 {\Omega}/Sq.), low mean absolute surface roughness (~1 nm), good optical transparency (~ 65 %), better stability and compatibility with the environment. The results indicate significant potential for applying stable ultrathin Ag film/electrode as a practical and economically feasible design solution for optoelectronic (transparent and conductive electrodes for solar cells and LEDs) and plasmonic devices. This film shows good conductivity, transparency, stability, and flexibility.