Localized atmospheric plasma sintering of inkjet printed silver nanoparticles

Abstract

Atmospheric pressure argon plasma sintering of silver nanoparticle inks was investigated to improve the plasma sintering process in terms of sintering speed, substrate friendliness and technical complexity. Sintering times were reduced to several seconds while achieving similar conductivity values of above 10% compared to bulk silver. Sintering can be carried out under ambient conditions at specific locations without exposing the entire substrate. Plasma sintering at atmospheric pressure exhibits the capability to be used in roll-to-roll production processes

Atmospheric pressure plasmas for surface modification of flexible and printed electronic devices: A review

“…[13] A Resistivity (ρ) of three inkjet printed silver nanoparticle inks after argon plasma sintering at atmospheric pressure or low pressure and after thermal sintering for different sintering time [57].…”

“…Generally, metal nanoparticles are dispersed in organic compounds in order to prevent agglomeration in the solvent and to improve processing. [57][58][59][60] After inkjet printing using metal nanoparticle ink, the metal nanoparticles are still surrounded by this organic shell, which acts as an insulating layer and prevents electron transfer between the particles. [57] To establish conductivity, conventional heating, [61][62][63][64] laser sintering, [65] microwave sintering [66][67] and high temperature plasma sintering [68][69][70] have been investigated.…”

“…Table 1 shows the resistivity results of the inkjet-printed silver nanoparticle ink after different sintering methods including low pressure plasma sintering (using 300W of a capacitively-coupled argon plasma from Diener Electronics in Germany), APP sintering (using the plasma pencil and plasma conditions shown in Figure 26), and thermal sintering (at 150 and 230 ℃). [57] Three different commercial silver nanoparticle inks were used. For thermal sintering, the three inks showed significantly different sintering speed and final conductivity, probably due to their different metal loadings, particle sizes, solvent systems and stabilizing agents.…”

“…22(b))show an exponential decay in resistivity with increasing energy to the substrate during the plasma sintering. The authors believe that it is caused by the increased ionization of the plasma gas and, as a consequence, the energetic ions as well as ultraviolet (UV) radiation from the plasma decreased the chain length of the organic binding material around the nanoparticles [55,57,61]. The differences in Ag line resistivity between glass and the polymer substrates are believed to be related to the wettability and the thermal conductivity of the substrate which strongly affects sintering [61].…”

Laser Direct Writing of Conductive Silver Micropatterns on Transparent Flexible Double-Decker-Shaped Polysilsesquioxane Film Using Silver Nanoparticle Ink

“…This represents a significant drawback in implementation of large-area production of printed electronics, being unfavorable in terms of cost. Moreover, to avoid such interference with the thermal properties of the polymer, sintering with microwave heating, 17 Ar plasma, 18,19 ultraviolet (UV) irradiation, 20 and flash light irradiation [21][22][23][24][25][26] have been considered as alternatives. Furthermore, the long sintering time of 30 min or more that is generally required to create conductive features also hinders industrial implementation.…”