Improved Long-Term Reliability of a Silica-Encapsulated Perovskite Quantum-Dot Light-Emitting Device with an Optically Pumped Remote Film Package

Abstract

In this study, inorganic perovskite (CsPbBr3) quantum dots are wrapped in SiO2 to provide better performance against external erosion. Long-term storage (250 days) is demonstrated with very little changes in the illumination capability of these quantum dots. While in the continuous aging procedure, different package architectures can achieve very different lifetimes. As long as 6000 h of lifetime can be expected from these quantum dots, but the blue shift of emission wavelength still needs more investigation.

Colloidal Quantum Dot Enhanced Color Conversion Layer for Micro LEDs

“…Another important parameter is the color conversion efficiency (CCE) which compares before and after conversion layer was placed. The difference of the spectral intensity at blue (or UV) and QD-emission bands can be used to figure out the overall conversion efficiency [17,26]:…”

“…The high CCE value can be viewed as an indicator of highly utilized pumping photons in the system, while the low CCE number can mean the loss of photons in the structure is high. A traditional PDMS (poly-dimethylsiloxane) /QD packaged LED can usually reach 30% or 40% [26].…”

A Metal-Embedded Packaging Structure for Performance Enhancement in Quantum-Dot-Converted LEDs

“…Colloidal quantum dots (CQDs) are considered promising materials for fabricating optoelectronic devices, such as solar cells and light-emitting diodes (LEDs), because they afford unique optical properties such as high quantum yield, variable color emission, and narrow emission linewidth [1][2][3][4][5][6][7][8][9]. Direct electrically driven or optical pumping methods have proved effective for exciting quantum dots (QDs) [10].…”

“…CQDs are sensitive towards environmental factors such as temperatures, and their illumination capabilities are susceptible to high temperatures. In the past, many works focused on enhancement of CQD lifetime have been published [5,16,17]. One possible solution to this problem is to mix a high thermal-conductivity material with the CQDs to expedite heat transfer [5,15].…”

“…In the past, many works focused on enhancement of CQD lifetime have been published [5,16,17]. One possible solution to this problem is to mix a high thermal-conductivity material with the CQDs to expedite heat transfer [5,15]. Although this mixing-based approach increases the average thermal conductivity, the host material (usually, silicon or polydimethylsiloxane [PDMS]) still occupies the majority of the volume, and the thermal dissipation can remain poor owing to discontinuous thermal paths among CQDs and high thermal-conductivity materials and host materials.…”