Role of Sputter Deposition Rate in Tailoring Nanogranular Gold Structures on Polymer Surfaces

Abstract

The reproducible low-cost fabrication of functional polymer-metal interfaces via self-assembly is of crucial importance in organic electronics and organic photovoltaics. In particular, submonolayer and nanogranular systems expose highly interesting electrical, plasmonic, and catalytic properties. The exploitation of their great potential requires tailoring of the structure on the nanometer scale and below. To obtain full control over the complex nanostructural evolution at the polymer-metal interface, we monitor the evolution of the metallic layer morphology with in situ time-resolved grazing-incidence small-angle X-ray scattering during sputter deposition. We identify the impact of different deposition rates on the growth regimes: the deposition rate affects primarily the nucleation process and the adsorption-mediated growth, whereas rather small effects on diffusion-mediated growth processes are observed. Only at higher rates are initial particle densities higher due to an increasing influence of random nucleation, and an earlier onset of thin film percolation occurs. The obtained results are discussed to identify optimized morphological parameters of the gold cluster ensemble relevant for various applications as a function of the effective layer thickness and deposition rate. Our study opens up new opportunities to improve the fabrication of tailored metal-polymer nanostructures for plasmonic-enhanced applications such as organic photovoltaics and sensors.

Nucleation and Growth of Magnetron‐Sputtered Ag Nanoparticles as Witnessed by Time‐Resolved Small Angle X‐Ray Scattering

“…The employment of highly nonequilibrium conditions favors tailoring the morphology of resultant NPs which strongly depends on the rate with which NPs equilibrate themselves with the ambient gas . Furthermore, mixing of two or more metals can be realized either simultaneously or sequentially giving rise to a wealth of homogeneous or heterogeneous nanoalloys, unattainable by conventional means .…”

“…The employment of highly nonequilibrium conditions favors tailoring the morphology of resultant NPs which strongly depends on the rate with which NPs equilibrate themselves with the ambient gas. [2][3][4][5] Furthermore, mixing of two or more metals can be realized either simultaneously or sequentially giving rise to a wealth of homogeneous or heterogeneous nanoalloys, unattainable by conventional means. [6][7][8][9][10][11][12][13][14][15][16][17][18] Despite great progress in laboratory synthesis of novel NPs with advanced functionalities, commercial applications of magnetron-sputtered NPs are still far from being at hand.…”

Magnetron-sputtered copper nanoparticles: lost in gas aggregation and found by in situ X-ray scattering

“…The method has acquired particular popularity as is evidenced by an increasing number of papers that have been published in recent years. Single-metal, [4][5][6][7][8][9][10][11][12][13][14][15] alloyed [16][17][18][19][20][21][22][23][24][25][26] and heterostructured NPs [27][28][29][30][31][32][33][34][35][36][37][38][39][40] have been successfully synthesized.…”

Molecular dynamics simulation of Ag–Cu cluster growth on a thin polymer film

“…[3,16,17] The resulting class of materials, namely metal-polymer nanocomposites, has been the subject of many experimental and theoretical studies in recent years. [18][19][20][21][22][23] They are of particular interest because the interplay between their constituents with contrasting properties may lead to new functional applications, [24][25][26] and they offer the potential for high-quantity and low-cost fabrication with reproducible properties. [27] The most challenging aspect of the computational treatment of such systems is the fact that typical physical vapour deposition processes take several seconds or minutes.…”