Researchers develop polarized LCD backlighting unit based on semipolar microLEDs and perovskite materials
Researchers from several Universities in China developed a self-polarizing RGB device utilizing semipolar microLEDs and perovskite based films aimed at improving backlight applications.
Structure of an LCD based on semipolar blue μLEDs excite anisotropic perovskite NCs as backlight. Image from Opto-Electronic Advances
In standard LCD displays, the backlighting units emits non-polarized light, which then results in an almost 50% light loss as this light has to pass through a polarizer (this is part of the LCD light path). The newly developed high-performance device is designed to emit RGB polarized light which results in higher efficiency and no light-loss dueo to the LCD filter.
Stanford researchers funded by Samsung develop new stretchable skin-like electronics suitable for microLED driving
Researchers from Stanford, led by prof. Zhenan Bao, developed skin-like stretchable electronic devices, using ag new design and fabrication process. The researchers say that the newly developed methods enable devices that are five time smaller and one thousand faster than their previous devices.
The new stretchable devices are powerful and fast enough to drive microLEDs, and indeed the researchers demonstrated driving 60Hz microLED arrays. The devices can also be used to drive sensors.
STRATACACHE to integrate Lumiode's backplane deposition technology in its microLED fab in Eugene, Oregon
US-based signage leader STRATACACHE announced that it has signed a strategic research and IP licensing agreement with US-based Lumiode that will enable STRATACACHE to integrate Lumiode's technology in its upcoming E4 microLED production line in Eugene, Oregon.
Lumiode's technology enables the deposition of an active matrix backplane directly on the LED structure. Lumiode's technology enables the production of both large-area displays and small microdisplays, and it is likely that STRATACACHE is interested in the former.
KAIST researchers develop a universal selective transfer process via micro-vacuum force
Researchers from Korea's KAIST institute developed a new microLED selective mass transfer process based on micro-vacuum force. The researchers brand their technology as micro-vacuum assisted selective transfer printing (µVAST), and say that it can be used to transfer a large number of microLEDs by adjusting the micro-vacuum suction force.
The process starts by forming small (20 micron, in the researchers demonstration device) holes on glass substrates using fast (7000 holes-per second) laser-induced etching (LIE). The LIE-drilled glass substrate is then connected to vacuum channels, which are controlled for selectively picking up, and the releasing, microLED devices.
Researchers succesfully grow GaN microLED arrays on a flexible graphene substrate
Researchers from Korea's Seoul National University and Sungkyunkwan University developed a method to grow GaN LED arrays on a flexible graphene layer. The so-called microdisks arrays exhibit excellent crystallinity with a uniform in-plane orientation and strong blue light emission.
The researchers grew the GaN microdisks on a graphene layer (grown on a sapphire substrate) covered with a micro-patterned SiO2 mask using metal–organic vapor-phase epitaxy. The microdisks were then processed into micro-LEDs and then successfully transferred onto bendable substrates.
MicroLED presentations from last year's microLED virtual meeting from UCSB, Coherent and Yole Intelligence
MicroLED-Connect is an upcoming hybrid event series, a year-long program of virtual and onsite events, all focused on the microLED industry. The first MicroLED Connect virtual event is coming up later this month, a 2-day virtual event that will be focused on microLED (and also miniLED) technologies. The event will include over 25 lectures from leading companies, researchers and market analysts. The series is organized by the MicroLED Industry Association together with TechBlick.
In this post we share three online presentations, taken from last year's online microLED event (November 2022). The first video, above, is from the SSLEEC group (led by Prof. Denbaars and Prof. Nakamura) at the University of California, Santa Barbara, that discusses the latest microLED research performed at this world-renowned group.
Researchers from Smartkem and Jiao Tong University demonstrate a high-performance organic-last integrated microLED display
Researchers from Shanghai Jiao Tong University together with UK-based OTFT developer SmartKem published a new paper describing the use of via interconnections in an organic-last integrated microLED display. The researchers report that the low-defect organic semiconductor backplane enables excellent performance.
As part of the project, the researchers demonstrated a 254 PPI active-matrix microLED display that achieves a brightness of 150,000 nits. The transistors exhibit superior performance in terms of milliampere driving current, and large ON/OFF current ratio approaching 1010 with excellent uniformity and reliability
KOPTI researchers develop promising new ZnO/GaN microLEDs
Researchers from the Korea Photonics Technology Institute (KOPTI) have developed highly efficient microLED devices. the researchers say that these new LEDs maintain an IQE of over 90% and are not effected by small chip site and increased current density.
The new microLEDs, branded as ZOGAN LEDs, are made from p-ZnO and p-GaN. The researchers say that the non-radiative leakage current is almost negligible and not increased as the chip size decreases even below 10 um. The researchers created blue ZOGAN LEDs in sizes 5, 10 and 20 um and confirmed the high performance in all these devices.
Micro-CPV: a promising new solar technology that may benefit from microLED production processes
Researchers from the Universidad Politécnica de Madrid and MIT, published a review article on Micro-Scale Concentrating Photovoltaics, or micro-CPV, a new technology that uses miniaturized solar panels and optics that concentrate the sun's energy into these micro panels. The benefits of micro-CPV compared to normal solar panels include potentially lower cost (much less solar absorption area), better thermal management, shorter optical path and lower resistive losses.
There are many challenges yet before micro-CPVs can be produced in large volume and at competitive prices. Interestingly, microLED production processes can be applied to the production of micro-CPVs, as these solutions can be seen like inverted technologies - tiny devices that either absorb or emit light.
ETRI researchers develop a highly efficient semiconductor chip packaging technology, applicable for microLED production
Researchers from Korea's ETRI institute developed a new chip packaging material, that is said to reduce the power consumption of the process by 95%, and reduce the number of required stages from 8 to 3. This could make semiconductors production much more efficient and lower in cost.
The technology is applicable to all high-end semiconductor production - including microLED production. Indeed the team reports that they have reached out to several microLED developers to evaluate the technology, and the initial testing has been very positive. The material could be commercialized in three years.
