The next battle in the LED phosphor industry stems from the rapid growth of LED applications that require warm colors and saturated reds in display or residential and retail lighting. For these, additional red and/or green phosphors are added to the mix. Nitrides and Oxynitrides offer excellent performance but are both controlled by Denka and Mitsubishi Chemicals, with strong IP obtained from NIMS. Market price for these materials is 5x to 10x higher than that of yellow phosphors.
Multiple organizations are therefore scrambling to develop better, cheaper and non IP-restricted compositions. Tungstates, molybdates, carbidonitrides, Green Aluminates and Selenides are being investigated. In addition, Quantum Dots are finally emerging as a credible alternative to traditional phosphor in some applications.
But phosphor composition is not the only key factor. Manufacturing technology, deposition methods and system design all have significant impact on LED and overall system cost and performance. This report provides a detailed list of established and emerging compositions and deposition technologies.
REMOTE PHOSPHORS COULD PRESENT A SIGNIFICANT UPSIDERemote phosphors offer significant benefits in terms of system performance and efficiency. However, they increase the required amount of phosphor material and associated cost by orders of magnitude. This constitutes the major roadblock for adoption. With some applications though, remote phosphors are the best option for reaching the required performance, and the additional phosphor cost can be partially or completely offset at the system level by improving the overall performance and reducing component count. The adoption of remote phosphors is decided on a case-by-case basis depending on the application, performance and cost targets. A RARE EARTH SHORTAGE COULD IMPACT THE LED INDUSTRY IN THE MID-TERM While supply constraints on Light Rare Earth should ease soon, tension will persist for the heavier elements, including Yttrium, Terbium and Europium, which are critical to both fluorescent lamp and LED makers. Shortages could appear and persist even after 2015. Fluorescent lamp is the major application competing with LED for these resources. In the short-term, as incandescent and other inefficient light sources are phased out of the market in most countries, the consumption of fluorescent lamps will increase significantly, putting additional strain on supply.