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Sintering of nanoparticles deposited onto rigid or flexible substrate is required for many devices that use continuous and patterned thin films. An emerging need in this area is to perform nanoparticle sintering under ambient conditions, at high speeds, and with throughput that is compatible with high speed nanoparticle deposition techniques. Intense Pulsed Light sintering (IPL) uses a high energy, broad area and broad spectrum beam of xenon lamp light to sinter metallic and non-metallic nanoparticles. The capability of IPL to meet the above needs has been demonstrated. This paper experimentally examines temperature evolution and densification during IPL. It is shown, for the first time, that temperature rise and densification in IPL are related to each other. A coupled optical-thermal-sintering model on the nanoscale is developed, to understand this phenomenon. This model is used to show that the change in nanoscale shape of the nanoparticle ensemble due to sintering, reduces the optically induced heating as the densification proceeds, which provides a better explanation of experimental observations as compared to current models of IPL. The implications of this new understanding on the performance of IPL are also discussed.
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A Hybrid Desktop Process for Integrated Deposition and Low-cost, In-situ Sintering of Conductive Silver Nanoparticles
Microscale continuous thin films or patterned conductive structures find applications in thin film electronics, energy generation and functional sensor systems. An emerging alternative to conventional vacuum based deposition of such structures is the additive deposition and sintering of conductive nanoparticles, to enable low temperature, low-cost and low energy fabrication. While significant work has gone into additive deposition of nanoparticles the realization of the above potential needs nanoparticle sintering methods that are equally low-cost, in-situ, ambient condition and desktop-sized in nature. This work demonstrates the integration of non-laser based, low-cost and small footprint optical energy sources for ambient condition sintering of conductive nanoparticles, with wide-area aerosol jet based additive printing of nanoparticle inks. The nanoparticle sintering is characterized by quantifying the sintering temperatures, sintered material conductivity, crystallinity, optical properties, thickness and microscale morphology in terms of the sintering parameters. It is shown that such optical sintering sources can be further integrated with inkjet printing as well, and the implications on new paradigms for hybrid additive-
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- Award ID(s):
- 1809289
- PAR ID:
- 10063286
- Date Published:
- Journal Name:
- World Congress on Micro and Nano Manufacturing
- Page Range / eLocation ID:
- 4
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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