Most LEDs today rely on a combination of Indium Gallium Nitride (IGN) and Yellow Phosphor (YP) emitters to produce white light. Recently, researchers have developed an inexpensive yet more luminosity-emitting alternative using silicon carbide, leading to cost reduction and higher luminosity output from LEDs. Silicon Carbide ceramic is a third-generation semiconductor material commonly used to fabricate dies, discrete Schottky diodes and power MOSFETs.
Silicon carbide (SiC) substrate material for LEDs can save costs in many ways. For instance, it reduces both module costs and overall system expenses while simultaneously decreasing energy use and weight of devices. Furthermore, SiC provides better heat dissipation which enables higher current densities with lower power losses in LED operation.
SiC is an excellent insulator, meaning it doesn’t absorb light like sapphire does when used for traditional LED devices. This makes it much better suited for high-power LEDs that must generate and disperse heat simultaneously; plus it enables fabrication of vertically structured LEDs without needing both n-type and p-type electrodes as is usually necessary with traditional horizontal sapphire-based models.
As electrification spreads to cars, electric transmission systems, and solar energy fields, power electronics must meet higher performance characteristics than ever. Silicon carbide offers various desirable qualities over silicon (Si), including increased switching speeds and superior thermal performance compared to its silicon counterparts – these advantages result in better efficiency, power density and electromagnetic interference (EMI) reduction for more advanced products designed for many different applications.
Silicon carbide ceramic is pioneering a revolution in power electronics. As a third-generation semiconductor material, its superior performance over silicon sets it apart. This includes higher breakdown electric field levels, thermal conductivity levels, electron saturation rate rates and radiation resistance ratings compared to its counterpart – not to mention its wider bandgap that allows it to work at higher frequencies and voltages.
Silicon carbide has an exceptionally high thermal conductivity for use in LEDs – three times greater than silicon. Furthermore, it features low lattice mismatch with gallium nitride making it suitable as a new generation substrate material for LEDs.
The LED industry is currently experiencing a paradigm shift as more efficient devices replace less efficient ones in applications like electric vehicles and renewable energy systems. This transition has particular resonance for high-power applications like driving systems like these.
To achieve these results, devices must feature both an extended lifespan and increased efficacy – meaning they must last throughout each day while producing more lumens than their predecessor. To accomplish this goal, high-performance materials must be utilized.
SiC substrates are ideal for LEDs because they offer the longest rated lifetime on the market and deliver maximum lumens per watt efficiency. Cree reports that its XHP LEDs boast an L70 rating of 35,000 hours with 112 lumens/W efficacy while dissipating 16.1 W in total dissipation.
Wider Range of Applications
Scientists from LiU and DTU have achieved an important step forward in the development of silicon carbide ceramic LEDs. Utilizing two steps – doping and surface structure modification – the researchers managed to produce white light through combination. This allows a greater range of colour tones than with blue-emitting gallium nitride LEDs currently found in many products such as laptops, smartphones and tablet computers.
Researchers created bright Si NCs/SiC multilayer LEDs featuring emission peaks at 500, 750 and 800 nanometers to increase LED intensity. P doping was found to significantly boost this intensity by passivating Si dangling bonds within multilayers and increasing radiative recombination; however, its effect may be mitigated when dopant concentration becomes excessive.
An approximate linear relationship exists between integrated EL current density and applied voltage, suggesting that carrier transport mechanisms in this device are predominantly driven by FN tunneling. Engineers using LEDs designed by LED manufacturers will be able to create devices with reduced power consumption, leading to smaller and more energy-efficient lighting fixtures. LEDs may also help telecom operators convert NIR light wavelengths into telecom wavelengths for use by them; additionally this technology could be useful for high speed photonic applications that need NIR radiation such as medical diagnostics/imaging or optical data communication.