Researchers develop a new method to deposit high-brightness green InGaN microLED arrays

Researchers from the University of Sheffield a new fabrication process for green InGaN microLEDs that achieves high brightness compact microLED arrays.

Emission microscopy of efficient InGaN green microLEDs (University of Sheffield)

Today most green InGaN microLEDs are produced by combining a standard photolithography technique with subsequent dry-etching processes on a standard III-nitride LED wafer. The researchers found a way to avoid the dry-etching processes which damage the surface the resulting LEDs. In the new process, the InGaN stack is direectly grown within pre-patterned micro-hole arrays through a thin (500nm) SiO2 layer serving as a GaN template over the epitaxial wafer.

The Perovskite Handbook - 2020 edition

MicroLED-Info and Perovskite-Info are happy to announce the 2020 edition of The Perovskite Handbook. This book is a comprehensive guide to perovskite materials, applications and industry, and it is now updated to January 2020 and lists recent developments and new companies, initiatives and research activities.

Perovskites are an exciting class of materials that feature a myriad of exciting properties. Perovskites are now entering the display market, with applications in quantum dots, LEDs, lasers and more.

The Perovskite Handbook

Reading this book, you'll learn all about:

  • Different perovskite materials, their properties and structure
  • How perovskites can be made, tuned and used
  • What kinds of applications perovskites are suitable for
  • Perovskites Quantum Dots
  • Perovskite solar cells, their merits and challenges
  • Perovskites-based LEDs
  • The state of the perovskite market, potential and future

iBeam Materials shows how to deposit both FETs and microLEDs directly on flexible metal foil substrates

iBeam Materials announced that it had successfully demonstrated the ability to produce high-performance GaN Field-Effect Transistors (FETs) directly on thin, flexible and rollable metal foil substrates.

This new technology complements iBeam's microLED deposition technology (demonstrated in the video above), and these FETs can be integrated with microLED chips in a side-by-side architecture. Both FETs and MicroLEDs are deposited on the flexible substrate without any transfer process.

Korean companies develop packaged RGB microLED technology for easier transfer process

Seoul Viosys and Seoul Semiconductors have jointly developed a new MicroLED technology, called Micro Clean LED that basically packages three separate LEDs (red, green and blue) into a single "one-single MicroLED pixel".

The idea is that these packaged colored pixels will be easier to transfer to the target substrate compared to the transfer of three different LEDs. The package itself does not contain any driver ICs.

KAIST researchers use 3D stacked MicroLEDs to enable high density displays

Researchers from the Korea Advanced Institute of Science and Technology (KAIST) developed a new process that enables the fabrication of highly dense MicroLED displays - up to 63,500 PPI (!).

The technique involves stacking RGB LEDs in three dimensions and a semiconductor patterning process. Stacking LEDs one on top of the other creates color interference issues, and to overcome this the researchers deposited an insulating film between the layers. This also improved the efficiency of the microLED devices.

Plessey develops the world's first InGaN on Silicon red LED

UK-based GaN-On-Si MicroLED microdisplay developer Plessey Semiconductor announced that it has successfully developed the world’s first GaN on Silicon-based Red LED.

Plessey native red InGaN LED, on silicon photos

Red LEDs are typically based on AlInGaP materia, or are color-converted from blue LEDs. These red LEDs limit the efficiency and the ability to create ultra-fine pitch sub pixels. Plessey says that InGaN red LEDs will also offer lower manufacturing costs, scalability to larger 200 mm or 300 mm wafers and better hot/cold factor over incumbent AlInGaP-based Red.

Plessey developed a process to deposit native green and blue microLEDs on the same wafer

UK-based GaN-On-Si MicroLED microdisplay developer Plessey Semiconductor announced that it managed to deposit native blue and green microLEDs on the same wafer. Plessey’s new patented process forms microLEDs that exhibit high current density operation and long operational lifetime.

Plessey native green and blue microLEDs wafer photo

Plessey said that to achieve this important milestone they had to overcome several challenges - including a magnesium memory effect, diffusion from the p-type cladding of the lower junction into the upper junction and the requirement for the precise tuning of the thermal budget during the growth of the second junction to prevent indium phase separation in the blue active region.