Enhanced copper micro/nano-particle mixed paste sintered at low temperature for 3D interconnects

Journal Article · Mon Jun 27 00:00:00 EDT 2016 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4954966· OSTI ID:22590658

Dai, Y. Y.; Anantha, P.; Ng, M. Z.; Li, Z. G.; Gan, C. L. ^[1]; Lin, Y. D. ^[2]

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1. NTU-Lockheed Martin Joint Lab, Nanyang Technological University, Research Techno Plaza, 50 Nanyang Drive, Singapore 637553 (Singapore)
2. School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)

An enhanced copper paste, formulated by copper micro- and nano-particles mixture, is reported to prevent paste cracking and obtain an improved packing density. The particle mixture of two different sizes enables reduction in porosity of the micro-paste and resolves the cracking issue in the nano-paste. In-situ temperature and resistance measurements indicate that the mixed paste has a lower densification temperature. Electrical study also shows a ∼12× lower sheet resistance of 0.27 Ω/sq. In addition, scanning electron microscope image analysis confirms a ∼50% lower porosity, which is consistent with the thermal and electrical results. The 3:1 (micro:nano, wt. %) mixed paste is found to have the strongest synergistic effect. This phenomenon is discussed further. Consequently, the mixed paste is a promising material for potential low temperature 3D interconnects fabrication.

• OSTI ID: 22590658
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 26 Vol. 108; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COPPER
DENSITY
ELECTRON SCANNING
FABRICATION
IMAGE PROCESSING
IMAGES
MIXTURES
NANOPARTICLES
POROSITY
SCANNING ELECTRON MICROSCOPY
TEMPERATURE RANGE 0065-0273 K