MicroLED inspection

MicroLED display developer VueReal announced a strategic partnership with Toray Engineering. As part of this collaboration, VueReal will integrate Toray's TASMIT 3000SR-Ⅲ300 PL inspection tool into its turnkey MicroSolid Printing platform. The announcement mentions several customized and optimized tools, but does not provide more details.

VueReal and Toray say that the PL inspection tool 3000SR-Ⅲ300 seamlessly integrates with VueReal's MicroSolid Printing platform to further reduce surface inspection device review time and contribute to greater inspection efficiency. This system acquires images of defects with a high level of magnification and categorizes defect types.

Last month Apple decided to cancel its microLED Watch project, which had very bad consequences for many microLED developers. Ams-Osram is still considering its options and it estimates its loss at $650-900 million, while Singapore-based electronics assembly solutions provider Kulicke & Soffa announced that it was also effected, to the tune of $110-130 million as it cancelled its own project with Apple.

KLA Corporation recently announced that it is withdrawing from the FPD market altogether. The company entered this market when it bought Israeli Orbotech for $3.4 billion, developer of inspection equipment for the semiconductor and display industries. 

Toray Engineering announced a technical partnership with semiconductor test equipment supplier Advantest Corporation, to promote efficient combined production systems for miniLEDs and microLED displays.

Toray Engineering will able to offer a combined inspection, transfer, and mounting systems, by data linking its systems with Advantest's inspection equipment. The company says that these integrated systems will enable the acceleration of microLED R&D and production. 

Rayleigh Vision was established in 2023 in Hong Kong, to developed stacked microLED microdisplay technologies. The company's technology enables the stacking of LEDs on top of each other, to create high-density displays. The company's founder and CEO, Prof. Jr-Hau HE, will give a talk at the upcoming MicroLED-Connect startup showcase event on February 2024, and was kind enough to answer a few questions we had regarding the company's status, technology, and his views on the microLED industry and market.

Hello Prof. Jr-Hau, Can you tell us a bit your company, and technology, and your next steps?

Rayleigh Vision is a company that specializes in disruptive MicroLED technology, with a focus on solutions for full-color microdisplays. Our team includes pioneers in MicroLED technology, who have over a decade of experience in this field.

Although we've seen significant advancements in MicroLED technology, challenges remain. These include developing a full-color solution for microdisplays, improving mass transfer efficiency, and enhancing process yields. From the perspective of microdisplays, achieving a full-color display with a high Field of View (FOV) and Pixels per Degree (PPD) is crucial for an immersive Extended Reality (XR) experience. However, no product currently on the market meets these specifications. 

MicroLED-Connect is a hybrid event series, a year-long program of virtual and onsite events, all focused on the microLED industry. The first online 2-day webinar was hosted successfully last month, with over 25 lectures (all recordings accessible for pass holders). The next event is a startup showcase, that will be hosted on February 22, 2024.

The startup showcase includes lectures from 8 leading microLED startup companies, covering topics such as microdisplays, AR headset development, microLED production, transfer processes and microLED inspection.

Now is a great time to reserve your ticket and make sure you stay updated with the latest innovation from the following startup companies: Rayleigh Vision, Inziv, Comptek Solutions, QustomDot, Terecircuits, iBeam Materials, Kura Vision and NS Nanotech. You can read the complete agenda here.

Exaddon developed a unique micro 3D Printing technology that enables it to produce probes that can access and test pads and bumps with pitches of less than 20 micron. The company says that this unique method halves the current limit of fine-pitch probing, enabling microLED developers testing options that haven't been available before.

Exaddon's μ3D printing technology delivers high quality printed metal with micrometer resolution. Exaddon’s initial microLED test array is 3D printed directly on prepatterned traces with a pitch of less than 20 μm; This demonstrator validates Exaddon’s process on microPCBs for mounting on current probe heads. With 128 probes, the array gives microLED testers a 64x increase in efficiency.

Researchers from the UK-based University of Strathclyde, led by Dr. Eleni Margariti, developed a new microLED transfer process, based on a continuous, single shot roller transfer printing process.

The researchers say that this process can enable large-scale integration of microLEDs. The system they developed can transfer an array of 320x240 pixels (over 75,000 microLEDs) in a single shot, with sub-micron relative position accuracy. The transfer printing process preserves the array geometry with pixel spatial location error less than 1 µm deviation from the as-designed layout. 

The researchers also employed an automated sub-micron precision metrology system based on simple optical microscopy, to asses such large device populations and allow the assessment of yield.

InZiv announced a new industrial-level microLED inspection system, called the REL. The company says that this new system provides unprecedented speed wafer-level EL testing of microLEDs. The REL system can rapidly obtain EL measurements on a microLED wafer, with up to 6 million LEDs in 1 hour.

The company's unique technology offers repeatable, high- accuracy measurements, with no damage to the device. The system is fully compatible with both vertical and flip-chip designs. InZiv says that the REL offers the most critical and reliable microLED inspection on the market, enabling the advancement of all microLED applications. The company is already working on its next-generation system, which will double the output.

Korea-based Top Engineering developed and launched a new microLED chip inspection tool, offering non-contact EL inspection.

The equipment can analyze LED chips directly on the epiwafer, and inspect thousands of microLED chips at the same time. The tool can use non-contact EL inspection on vertical microLED chips.

We're happy to interview InZiv, as part of our series of interviews with MicroLED Industry Association members. InZiv develops testing and inspection equipment for display makers focusing mostly on MicroLED displays (but also QLED and OLED).

Q: Can you introduce your company and technology?

InZiv is a leader in display testing and inspection, providing high-resolution testing and inspection equipment to today’s foremost advanced display developers and manufacturers. InZiv’s proprietary nano-optical technology specializes in microLED displays, but also extends to QLED and OLED. With the size of pixels now reaching the single-micron scale, our testing equipment provides comprehensive data and nanometric resolution, empowering display manufacturers to improve their manufacturing processes, lower production costs, and enable greater access to the use of these displays by all consumers. Based in Israel, the company was founded in 2018, and counts a number of the world’s leading display manufacturers among its customers.