Packaging and interconnect technologies for GaN nanowire-based light emitting diodes

Published

May 26, 2009

Author(s)

Norman A. Sanford, Myongjai Lee, Jen-Hau Cheng, Dragos Seghete, Steven M. George, John B. Schlager, Kristine A. Bertness

Abstract

GaN nanowires grown along c-axis on a silicon substrate using molecular beam epitaxy have been identified as one of the best materials for future light emitting diodes (LEDs). These defectfree nanowires-based LEDs may reach the highest possible efficiency due to their potentially excellent internal quantum and light extraction efficiencies. It is very challenging to interconnect these vertically aligned nanowires because of their small diameters, extremely high aspect ratios, and random distributions on the substrate. We have developed a novel packaging solution by encapsulating each nanowire with a nano-scaled, multilayer consisting of 50 nm thick alumina layers and 40nm thick tungsten layers for electrical and optical interconnects. Atomic layer deposition (ALD) processes have been applied to make such a multilayer due to ALD's excellent conformal coverage and precise thickness control. This nano-scaled multilayer also provides efficient thermal connections that are mechanically reliable. The internal, junction-to-substrate thermal resistance can be reduced by 400 times by plating copper surrounding the nanowires. With nano-scaled ALD alumina, we can establish an excellent thermal interface without electrical shorts. To characterize thermal performance of these nanowires, we have developed a photoluminescence measurement technique to measure the tip temperatures optically. The packaging and interconnect technologies developed for GaN nanowire-based LEDs are novel and can be applied to many other nanowire-based microsystems.

Proceedings Title

IEEE, Electronic Components and Technology Conference

Conference Dates

May 26-29, 2009

Conference Location

San Diego, CA

Pub Type

Conferences

Keywords

GaN nanowires, light emitting diodes (LEDs)

Citation

Sanford, N. , Lee, M. , Cheng, J. , Seghete, D. , , S. , Schlager, J. and Bertness, K. (2009), Packaging and interconnect technologies for GaN nanowire-based light emitting diodes, IEEE, Electronic Components and Technology Conference, San Diego, CA (Accessed April 20, 2024)