For the first time ever, researchers at the Siemens subsidiary Osram Opto Semiconductors were able to successfully produce gallium nitride LED chips on a silicon substrate instead of the much more expensive sapphire backing.
Silicon is a standard material in the semiconductor industry and is therefore an inexpensive and easily obtainable alternative. This development goes a long way toward making it possible for Osram to produce LED components at a much lower cost while maintaining the same level of quality and performance.
LEDs are an efficient and, above all, energy-conserving alternative to traditional types of room lighting. However, until now the manufacturing costs for LEDs have been higher than those of other more established types of lighting, so they have not been widely adopted for everyday use.
Using this new procedure, it should be possible to use large sheets of silicon for LED production, which would result in a major improvement of manufacturing efficiency. Osram has already succeeded in producing high-performance LED chips on a 150-millimeter (six-inch) wafer. Theoretically, one such wafer would be sufficient to produce 17,000 LED chips of one square millimeter each.
Researchers are already working on the adjustment of the production process to handle eight-inch wafers. This would increase the number of chips per substrate, thereby further reducing the cost of production. The first commercially available LED products using silicon-based chips are expected to be on the market in about two years.
These new thin-film-based LEDs are still only at the pilot stage and will have to be tested under real-world conditions. The blue and white silicon-based prototypes display performance characteristics that are on a par with the LEDs available on the market today. A blue chip measuring one square millimeter in a standard housing delivers a record brightness of 634 milliwatts at 3.15 volts. That's an efficiency rate of 58 percent. Those are excellent results for a chip of that size at a current of 350 milliamperes.
The development of these new manufacturing technologies is based on the specialized knowledge regarding the growth of artificial crystals that has been gathered by the researchers at Osram Opto Semiconductors.
The major breakthrough was a special epitaxy process which made it possible to slice off particularly stable silicon films without the cracking that has often been a problem in the past. At the same time, these silicon films are also comparable to sapphire backing with regard to the LEDs' brightness and stability.
Dr. Norbert Aschenbrenner | Siemens InnovationNews
'Stealth' material hides hot objects from infrared eyes
25.06.2018 | University of Wisconsin-Madison
Scientists print sensors on gummi candy: creating microelectrode arrays on soft materials
21.06.2018 | Technische Universität München
Russian researchers together with their French colleagues discovered that a genuine feature of superconductors -- quantum Abrikosov vortices of supercurrent -- can also exist in an ordinary nonsuperconducting metal put into contact with a superconductor. The observation of these vortices provides direct evidence of induced quantum coherence. The pioneering experimental observation was supported by a first-ever numerical model that describes the induced vortices in finer detail.
These fundamental results, published in the journal Nature Communications, enable a better understanding and description of the processes occurring at the...
In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.
Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
25.06.2018 | Physics and Astronomy
25.06.2018 | Earth Sciences
25.06.2018 | Power and Electrical Engineering