Showing posts with label microLED. Show all posts
Showing posts with label microLED. Show all posts

Tuesday, April 5, 2022

Picosun ALD and NYCU in Taiwan enhances micro-LED efficiency

ESPOO, Finland, 5th of April 2022 – Picosun Atomic Layer Deposition (ALD) has played a vital role in enhancing electro-optical characteristics of micro-LEDs in research done by National Yang Ming Chiao Tung University (NYCU) in Taiwan.

The usage of dielectric films as a passivation material is a popular technique to suppress dangling bonds as well as to improve output power and external quantum efficiency in LEDs. The study conducted at NYCU compared III-Nitride micro-LEDs of different sizes with and without ALD Al2O3 passivation. The results showed external quantum efficiency enhancement of 70% for 5 µm × 5 µm micro-LEDs and 60% for 10 µm ×10 µm micro-LEDs when using ALD Al2O3 passivation.



In addition, to achieve full color display, an inkjet printing to pattern quantum dots automatically has been developed at NYCU. The solution can considerably improve the precision of color pixels and satisfy the high-resolution requirements. Picosun ALD passivation technology was successfully used for preventing the quantum dots from photo-oxidation and degradation. After a 500 hours environmental reliability test, the color gamut remained at excellent level.*

“Micro-LED technology has been the disruptive technology in the next generation displays, and more application areas are emerging its benefits being long lifetime, high power efficiency and high brightness. With quantum dot-based technology micro-LEDs can be used in applications such as virtual and mixed reality as they allow the use of single-color, blue, micro-LED chips resulting in lower manufacturing costs. Our study has proved that ALD passivation plays a key role in upcoming nanometer-scale devices”, says Hao-Chung Kuo, professor at NYCU.

“Picosun’s ALD technology has been production-proven at many prominent LED manufacturers. ALD films’ superior conformality and uniformity, and their ability to ensure reliable, pinhole-free encapsulation even at extremely low film thicknesses is a key benefit. Furthermore, the ALD process can be run at moderate temperatures”, explains Juhana Kostamo, VP, Industrial Business Area of Picosun Group.

Thursday, November 5, 2020

Improving Curved uOLED encapsulation with ALD

[Beneq Blog] For the past decades, organic light emitting diodes (OLEDs) have become of great interests for applications to micro-displays. Unfortunately, these systems are highly sensitive to moisture and oxygen ingress and require high barrier encapsulation. Additionally, a specific protection needs to be added to protect the device from mechanical failure. Depending on the application, various options from glass lids to flexible barriers have been developed. The former offers high mechanical protection but suffers from long implementation processes, while the later typically exhibit low hardness and poor wear resistance.

Pinhole free encapsulation via ALD deposited directly onto micro-OLEDs means simpler manufacturing and robust protection. The thinner ALD encasement enable substrate bending and open the possibility of more compact curved devices with less complex optical engines.

Continue reading at BENEQ: LINK

Friday, February 7, 2020

Veeco Introduces Suite of MOCVD Systems to Enable High Performance Photonics Devices

Plainview, N.Y. - Veeco Instruments Inc. (Nasdaq: VECO) introduced today the Lumina Metal Organic Chemical Vapor Deposition (MOCVD) platform, which incorporates the proprietary TurboDisc® reactor technology for outstanding film uniformity, yield and device performance for a variety of photonics applications. This new MOCVD platform, including the Lumina R480™ and Lumina R480S™ models, will accelerate the production of VCSEL, Edge-Emitting Laser (EEL) and Mini / Micro LED devices. 
 

(Image: Veeco)

In response to strong consumer demand for arsenic phosphide (As/P) MOCVD technology, the Lumina platform is advancing a new generation of high-efficiency photonics devices including VCSELs used in 3D sensing, autonomous driving and high-speed data communication. The Lumina platform is also designed for mini and micro LED production for advanced displays found in next-generation 4K and 8K televisions, smartphones and wearable devices, as well as EEL devices used for advanced optical communications and silicon photonics applications.

“Leading photonics manufacturers are currently seeing the benefits of our Lumina MOCVD system and are validating its impact in the manufacturing of high-volume photonics devices,” said Gerry Blumenstock, Senior Vice President, Product Line Management. “As the world’s leader in MOCVD equipment, the Lumina platform is the answer for the next generation VCSEL, EEL andmini / micro LED devices. With its proven design, technology and performance, Lumina provides exciting opportunities for the next generation of photonics devices.”

The Lumina R480 and R480S systems are based on Veeco’s industry leading MOCVD TurboDisc® technology which features excellent uniformity and low defectivity over long campaigns for exceptional yield and flexibility. In addition, Veeco’s proprietary technology drives uniform thermal control for excellent thickness and compositional uniformity. Providing a seamless wafer size transition, the system is capable of depositing high quality As/P epitaxial layers on wafers up to six inches in diameter. The R480 and R480S systems allow users to customize their systems for maximum value.

Veeco will be exhibiting at Photonics West in San Francisco, CA from Tuesday, February 4 to Thursday, February 6. Stop by booth number 1456 to learn more about Veeco’s MOCVD and ion beam sputtering solutions for photonics applications.

Wednesday, November 13, 2019

Improvement of the quantum efficiency of micro LED by ALD passivation

Micro LED has been interested in the next generation display and been actively developing at many electronics manufactures and institutes for applications of AR/VR, wearable device and extra-large display as a core factor of the forth industry. Also it is evaluated to have superior properties to LED as well as OLED with low power consumption, excellent brightness, greater contrast, flexibility and reliability.

Micro LED of less than 10 µm size is required for displays needed high pixel per inch (PPI) but the quantum efficiency drop would occur by sidewall effect in the manufacturing process. Looking at the reason in detail, micro LED chips require separation of them by dry etching process and the sidewall effect reducing external and internal quantum efficiency happens not to optimize extraction of light by chemical contaminations and structural damages during the etching process.

ALD passivation on the sidewall of Micro LED after dry etching process

The passivation of sidewall by atomic layer deposition recover and remove the plasma damage by dry etching so that the quantum efficiency could be increased and also the ratio of improvement could increase as small as the size of micro LED.

Specially, the interest of productive ALD equipment has been gradually increased because of the excellent dielectric passivation by ALD Al2O3 thin films expecting to improve quantum efficiency.

NCD has been developing wafer based high throughput batch ALD system continuously enable to form high quality oxide passivation to improve the quantum efficiency of micro LED. By introduction of the system in production of micro LED, it could be expected to guarantee the productivity, high quality and performance reliability of high resolution micro LEDs for applications of AR/VR, flexible and wearable devices and extra-large displays.  

NCD Si wafer based batch ALD cluster system