Chinese Researchers Develop Phosphor-free White Light from Nanopyramid LEDs

A novel nanopattern technique of nanospherical-lens photolithography is introduced to fabricate the InGaN nanopyramid white (NPW) light-emitting diodes (LEDs) by selective area growth. Highly ordered NPW LED arrays are achieved after optimizing the growth conditions. It is found that the NPW LEDs vary from warm white light to cool with the increase in growth temperature.

Schematic illustrations of the fabrication process flow for phosphor-free nanopyramid LEDs by the NLP method. (graphic courtesy of Journal of Applied Science)

For the cool white NPW LEDs, the spectrum is similar to the conventional white LEDs obtained from the blue LEDs combined with yellow phosphors. The blue emission originates from the upper sidewalls of nanopyramids, and yellow light is mainly emitted from the lower ridges with respect to the base of nanopyramids. Furthermore, simulation shows that the light extraction efficiency of NPW LEDs is about 4 times higher compared with conventional ones, and the escape cone is as much as 85° due to their three-dimensional nanopyramid structures. These observations suggest that the proposed phosphor-free NPW LEDs may have great potential for highly efficient white lighting.

To read the rest of the report, please refer to the following link: Fabrication and optical characteristics of phosphor-free InGaN nanopyramid white light emitting diodes by nanospherical-lens photolithography

Disclaimers of Warranties
1. The website does not warrant the following:
1.1 The services from the website meets your requirement;
1.2 The accuracy, completeness, or timeliness of the service;
1.3 The accuracy, reliability of conclusions drawn from using the service;
1.4 The accuracy, completeness, or timeliness, or security of any information that you download from the website
2. The services provided by the website is intended for your reference only. The website shall be not be responsible for investment decisions, damages, or other losses resulting from use of the website or the information contained therein<
Proprietary Rights
You may not reproduce, modify, create derivative works from, display, perform, publish, distribute, disseminate, broadcast or circulate to any third party, any materials contained on the services without the express prior written consent of the website or its legal owner.
Display devices have been used for many years as a means of HMI (Human Machine Interface) to connect humans and machines interactively, and their usage are still expanding. Automotive interiors are no exception to this trend, with an increasing ... READ MORE
About LiDAR Automotive industry trends In recent years, many vehicles have been launched with ADAS (Advanced Driver Assistance Systems) as standard equipment. As the future evolves towards more automated driving, sensing around the vehicle i... READ MORE