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MicroLEDs offer an extraordinary combination of high luminance, high energy efficiency, low cost, and long lifetime. These characteristics are highly desirable in various applications, but their usage has, to date, been primarily focused toward next-generation display technologies. Applications of microLEDs in other technologies, such as projector systems, computational imaging, communication systems, or neural stimulation, have been limited. In non-display applications which use microLEDs as light sources, modifications in key electrical and optical characteristics such as external efficiency, output beam shape, modulation bandwidth, light output power, and emission wavelengths are often needed for optimum performance. A number of advanced fabrication and processing techniques have been used to achieve these electro-optical characteristics in microLEDs. In this article, we review the non-display application areas of the microLEDs, the distinct opto-electrical characteristics required for these applications, and techniques that integrate the optical and electrical components on the microLEDs to improve system-level efficacy and performance.
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Ultra‐Thin Ceramic Substrates for Improved Heat sinking for MicroLEDs
Abstract Micro light emitting diodes (MicroLEDs) provide unrivaled luminance and operating lifetime, which has led to significant activity using devices for display and non‐display applications. The small size and high power density of microLEDs, however, causes increased adverse heating effects that can limit performance. A new generation of electrically insulating high thermal conductivity materials, such as alumina, is proposed to mitigate these thermal effects when used as a substrate as an alternative to glass. This strategy can then be used as a method of passive heat sinking to improve the overall performance of the microLED. In this work, a newly available material, an 80 micron thick alumina ceramic substrate, is shown to yield a 30 % improvement on average in the maximum current drive over a glass substrate.
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- Award ID(s):
- 1926747
- PAR ID:
- 10449392
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 8
- Issue:
- 19
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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