High‐Efficiency, Microscale GaN Light‐Emitting Diodes and Their Thermal Properties on Unusual Substrates

Abstract

A method for forming efficient, ultrathin GaN light-emitting diodes (LEDs) and for their assembly onto foreign substances is reported. The LEDs have lateral dimensions ranging from ~1 mm × 1 mm to ~25 μm × 25 μm. Quantitative experimental and theoretical studies show the benefits of small device geometry on thermal management, for both continuous and pulsed-mode operation, the latter of which suggests the potential use of these technologies in bio-integrated contexts.

Self-powered flexible inorganic electronic system

“…High-quality inorganic-based flexible electronics, such as LEDs [95], high-density memories [96], and energy devices [32], can be realized by laser interfacial irradiation between a transparent mother substrate and laserreactive sacrificial layer. Several groups have demonstrated the fabrication of flexible GaN LEDs using LLO by melting the interface between a GaN and a sapphire wafer [97,98]. As with the flexible GaN LEDs transferred from a Si substrate, highquality epitaxial LED can be transferred onto a flexible substrate.…”

Full-Color Single Nanowire Pixels for Projection Displays

“…In addition, pixels of single nanowire-based LED arrays can be much more efficient in heat dissipation and can operate at extremely large injection current levels. [44][45][46][47] Critical to these technology developments is the demonstration of full-color, tunable light sources including LEDs and lasers using single, or a few nanowires on the same chip. This requires a precise tuning of alloy compositions in different nanowire structures and that these compositional 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 5 variations should be ideally introduced in a single growth/synthesis step.…”

Analytical investigations on the thermal properties of microscale inorganic light-emitting diodes on an orthotropic substrate

“…jzsong@zju.edu.cn µ-ILED device. 13,14 The µ-ILED has a dimension of 2a × 2b × h LED with 2a × 2b as the in-plane dimension and h LED as its thickness. The coordinate z points from the encapsulation layer to the substrate while x and y are the in-plane axis.…”

“…10,12,15 The specific heat capacity and density of the encapsulation layer (SU8) is 1200J/kg/K and 1090kg/m 3 . 14 Figure 5(a) shows the saturated temperature increase of the µ-ILED from the analytical predictions in Eq. (12) and finite element analysis for the duty cycle of 10% with the pulse period 0.1s.…”