Correcting MicroLED and OLED Display Quality to Improve Production Efficiency and Yields

This post was sponsored and authored by Radiant Vision Systems, LLC

Introduction

Emissive OLED, microLED (μLED), and miniLED are emerging as the next wave of technology in the display market. This is exciting because these displays promise improved display performance and visual appearance with greater efficiency than other display technologies, thanks to their individually emitting pixel elements. Both OLEDs and microLEDs have superior contrast ratios and sharper images with deeper blacks and more vibrant colors than traditional LCDs. These emissive displays require no backlight, resulting in thinner, lighter-weight displays that use less electricity. OLEDs also bring a dramatic boost in responsiveness, about 1,000 times faster than existing technologies, virtually eliminating blur on fast-moving and 3D video. MicroLEDs match OLED technology for response time and view-angle performance, but exceed OLED in brightness and ruggedness, with even lower power consumption.

Radiant correcting OLED and MicroLED display quality - figure 1

Figure 1 – The 219-inch microLED display “The Wall” by Samsung, shown at IFA 2019, September 6-11 in Berlin, Germany. (Source: Samsung)1

As manufacturers work to launch commercially viable emissive display products, high costs due to material prices and manufacturing yield issues have hindered widespread technology adoption—most dramatically in large-format implementations, as they drive up end-customer prices. The smartphone market has been the most successful segment for OLED technology to date and will likely be the catalyst that drives long-term adoption of OLEDs and microLEDs for other applications. Display Supply Chain Consultants (DSCC) cites smartphones as the dominant OLED market, accounting for around 91% of units per year with revenue share around 79% by 20222. Yole Développement (Yole) projects a similar trend for microLEDs, with a longer ramp up period, and a market reaching up to 330 million units by 20253. With this type of growth in demand, improvements in manufacturing efficiency are needed.

What to expect from SID Displayweek 2020? An interview with Sri Peruvemba, VP at SID

The SID DisplayWeek 2020, the premier event for the display industry, will take place in San Francisco (June 7-12). The MicroLED-Info team will attend this event, and we are happy to present this interview with Sri Peruvemba to discuss the upcoming event. Sri is a good friend and a board director and VP at SID.

Thanks for your time Sri - as Chair of Marketing at SID, please can you tell us a bit about DisplayWeek 2020?

I am proud to say that SID’s DisplayWeek is still the world’s most respected show on electronic displays, touchscreens and related materials. Everyone in the industry has a presence. The show has been growing for the past few years and last year we had a record attendance of over 8,000 people from all over the world. Factoring in global business and political environment, we expect DW2020 to be another record year evidenced by paper submissions, awards submissions, over 90% of the floor space sold out (we had expanded both floor space and meeting rooms), offers to sponsor various events and other factors.

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.

Rohinni demonstrates its latest MicroLED prototypes at CES 2020

Rohinni demonstrated its latest technology and prototypes at CES 2020, and this interesting video shows the company's booth and provides an interview with the company's CEO.

On display you can see some flexible lighting prototypes, an LCD display backlighting unit that uses mini LEDs, automotive solutions developed by the Rohinni and Magma JV, keyboard backlights from its Luumii JV and finally some microLED display prototypes made by the BOE Pixey JV.

Mojo Vision develops microLED-based AR contact lenses

In June 2019, AR developer Mojo Vision announced that it developed a 14k sub-pixel PPI Micro-LED microdisplay, to power its upcoming AR platform. The company now revealed that its technology actually embeds the microLED microdisplay in a contact lens.

Mojo Vision microLED contact lenses generations image (January 2020)

Mojo Vision has been in stealth mode until now - as the company finally revealed its technology and demonstrated a lens mounted to a handheld stick that you can peer through to see a demo loop comprised of green text overlaid on real world objects.

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

Plessey demonstrated its latest microLED displays and technologies at CES 2020

UK-based GaN-On-Si MicroLED microdisplay developer Plessey Semiconductor demonstrated several new microLED technologies at CES 2020. First up we have a Head Up Display (HUD) for automotive applications, that is based on a 0.7" blue monochrome MicroLED display:

Plessey 0.7'' blue FHD automotive microLED HUD (CES 2020)

This same display was demonstrated at SID DisplayWeek 2019, and uses JDC's silicon backplane. The next display is a native red InGaN microLED. This is the first time this display was demonstrated:

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.

Introducing The MicroLED Handbook

MicroLED-Info is proud to present The MicroLED Handbook. This book is a comprehensive guide to MicroLED display technology, industry and market. MicroLED displays are thin, efficient, bright and flexible and are on track to revolutionize the display industry.

The MicroLED Handbook

Reading this book, you'll learn all about:

  • MicroLED technology, materials and production processes
  • How MicroLEDs compare to LCDs and OLEDs
  • What are the challenges towards commercial production
  • LED technology and manufacturing processes
  • MicroLED driving and full-color architectures
  • The MicroLED displays currently on the market

Meet the MicroLED-Info team at MWC 2020

The MicroLED-Info team is excited to announce its attendance at the Mobile World Congress 2020 on February 24-27 in Barcelona, Spain. The Mobile World Congress (MWC) is the world's largest gathering for the mobile industry, organized by the GSMA. It features a large exhibition, conference programme and networking opportunities.

We are looking forward for a great event and great new microLED prototypes and technologies on display.