Technical / research - Page 2

Researchers from the University of Illinois Urbana-Champaign developed a new process to create transistors for high-performance microLED displays. The researchers say that this is the highest performing solution-processed semiconductor transistor to date, and a potential low-cost one.

The new method is based on ordered defect compound semiconductor CuIn5Se8 prepared by solution deposition. These transistors were used to form high-speed logic circuits operating in megahertz, to power a small 508 PPI blue microLED display (8 micron LEDs).

OTFT developer Smartkem, a MicroLED Industry Association member, announced that it has signed an agreement with Shanghai Chip Foundation Semiconductor Technology to co-develop microLED-based backlight units for LCD displays.

Smartkem prototype microLED display

The new backlight units will use Smartkem's proprietary organic dielectric single layer material, or Redistribution Layer (RDL). Chip Foundatiion will use the material with its own microLED devices. As part of the co-development project, Smartkem will develop specifica insulator materials to be used by Chip Foundation. The project will develop miniLED packages that contain four microLEDs wired in series. Smartkem says that the chip will offer high brightness, high current efficiency, improved uniformity and lower power consumption compared to current miniLED based backlighting units.

Researchers from Zhengzhou University, the Zhengzhou University of Railway Engineering and North Minzu University has developed a new method to improve the efficiency of deep ultraviolet (DUV) microLEDs.

The researchers explain that standard DUV microLEDs suffers from serious electron leakage, and low hole injection efficiency. And the smaller they get, the more sidewall defects reduce the efficiency even further. The researchers introduced polarized bulk charges into the hole supply layer and the electron  supply layer (p-HSL and n-ESL) to enhance the binding of carriers and increase the injection efficiency of carriers.

MicroLED-Connect is the world's first dedicated MicroLED conference and exhibition. The event, organized by TechBlick and the MicroLED Association, will take place at the High Tech Campus in Eindhoven, also known as "the smartest square kilometer in all of Europe", and will include an excellent conference program, masterclasses, tours - with a special emphasis on social/professional gatherings and networking opportunities. Register now to attend MicroLED-Connect and enjoy our special discount (up to 400 per ticket), valid until August 15, of up to 400 Euro.

One of the themes to be highlighted at the event is microLED material platforms, the basis of all microLED emission technology. As MicroLED technology competes with high-end and cost-effective OLED displays, microLED developers need to deeply innovate their material platforms and technologies and we believe that this is one of the keys for microLEDs' future success.

Researchers from HP propose a new composable monitor design - that is based on microLED display modules (tiles) that can connect together to construct complete monitors. The researchers explain that microLED is a key technology as it enables a bezel-less design.

The main idea is to create Lego-like building blocks, both flat and curved, that can connect in both horizontal and vertical configurations. 

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. 

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. 

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 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.