Quantum dots will be prescribed in MicroLED: virtuality ceases to be grainy
The MicroLED displays, like OLED, simple LEDs and the LEDs of the backlight in LCD screens, is produced approximately equally: a source of blue radiation, which by means of color filters or phosphor is converted into red and green spectra. The filters are passive, and the phosphor is extremely inefficient from the point of view of energy costs.
The solution was found in the form of quantum dots — special additives in the form of microparticles which absorb yourself in the blue spectrum and effectively radiate the pure spectra with different wavelength depending on the sizes of these incremental micro-particles, red and green. On sale you can find the monitors and TVs with lights on quantum dots and will soon begin to go OLED for quantum dot, in which the microparticles are added directly to the blue OLED. As it turned out recently, monolithic MicroLED displays, which are made directly on silicon wafers, can also be produce with the use of quantum dots.
The company Nanoco Technologies and Plessey Semiconductors announced that they have signed a partnership agreement for joint development, obtaining patents and the production of MicroLED based on quantum dots. In the mass production of “quantum” MicroLED will be launched in 2020 to 200-mm plant Plessey Semiconductors. The company Nanoco Technologies is responsible for the selection of materials and debug production, in order to achieve the same radiation characteristics over the entire surface of a 200 mm wafer.
The microLED displays will be produced on a gallium-nitride (GaN) wafers with a substrate made of silicon. The process is the technology of growing crystals for led blue glow. Only instead of the phosphor in some blue LEDs by inkjet printing will be made of microparticles of the desired size to create “red” and “green” quantum dots. In fact, is to create classic arrays of RGB triads. This technology will allow to reduce the size of the subpixels to 4 µm is a modern 30 µm, the size of which is limited to the minimum dimensions of the granules of the phosphor.
Reducing the size of subpixels to 87 % (more than 7 times) will have a positive impact on the resolution of the MicroLED. The grain size of the virtual image will be reduced nearly an order of magnitude. Pleased that the developers are planning to use “quantum” microLED for gaming headsets, virtual and augmented reality.