Abstract
The demand for the development of local laser sintering of nanoparticle arrays is explained by the expanding needs for printed electronics for functional microstructure formation, on heat-sensitive substrates in particular. This work is based on the research into the sintering of arrays of silver nanoparticles synthesized in a spark discharge and deposited on a substrate by focused aerosol flow. The sintering was done by continuous and pulsed lasers with wavelengths 527, 980 and 1054 nm. Sintered samples were studied by measuring the resistivity, cross-section profile area and microstructure features. The highest average conductivity, equal to the half of the bulk silver conductivity, was achieved when sintering by continuous radiation with a wavelength 980 nm. The results showed that when using pulsed radiation the direct heating of nanoparticles in the sample surface layer dominates with the formation of a pore-free conductive layer of around 0.5 μm thick and crystallite of 70–80 nm size. It was found that laser sintering by radiation with a wavelength 527 nm required an order of magnitude lower specific energy costs as compared to the longwave laser radiation. The high energy efficiency of laser sintering is explained by special conditions for radiation absorption at plasmon resonance.
Highlights
When forming electronic elements by printing with nanoparticles (NP), an important process that ensures the electronic properties of these elements is the sintering of NP arrays deposited on the substrate
Comparing the data on average specific conductivity σ(e) (Figure 4) and on microstructure (Figure 5, Table 2) of silver NP arrays sintered by four types of laser radiation, we assume that the best conductivity areas in all cases are non-porous external layers with thickness in the range
It is important to emphasize the basic regularities of local laser sintering by pulsed and CW radiation of silver NP arrays formed by dry aerosol printing
Summary
When forming electronic elements by printing with nanoparticles (NP), an important process that ensures the electronic properties of these elements is the sintering of NP arrays deposited on the substrate. Studies and applications of local laser sintering of NP arrays on substrates have been developing, which significantly expands the possibilities of micron-size printing methods in the areas of heat-sensitive plastic substrates and a variety of NP materials used [1,2]. The method of laser sintering of micron-size conductors from silver NPs and organic thin-film transistors on polyethylene naphthalate (PEN) substrates was studied in [3,4]. Most metals used for the synthesis of NPs, e.g., copper or aluminum, have a high oxidation reactivity in ambient conditions. It results in the formation of oxide insulating film 1–3 nm thick on a surface, preventing the high conductivity between particles. To prevent oxidation processes, it is possible to form samples in a high vacuum or in an inert gas environment [7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
