Abstract
Full-color displays are typically fabricated using a combination of chromatic materials of various types, introduced into an addressable pixel-based electronic device. Here we show that brightly colored, highly vivid pixels, directly suitable for RGB displays, can be fabricated using periodic areas of Al nanorods in each pixel. Both nanorod length and spacing are critically important in achieving strong and spectrally distinct scattering signatures across the visible spectrum. This use of a low-cost, abundant metal for achieving full-spectrum coloration is compatible with complementary metal-oxide semiconductor manufacturing methods and directly applicable to current liquid crystal display technology.
Aluminum is abundant, low in cost, compatible with complementary metal-oxide semiconductor manufacturing methods, and capable of supporting tunable plasmon resonance structures that span the entire visible spectrum. However, the use of Al for color displays has been limited by its intrinsically broad spectral features. Here we show that vivid, highly polarized, and broadly tunable color pixels can be produced from periodic patterns of oriented Al nanorods. Whereas the nanorod longitudinal plasmon resonance is largely responsible for pixel color, far-field diffractive coupling is used to narrow the plasmon linewidth, enabling monochromatic coloration and significantly enhancing the far-field scattering intensity of the individual nanorod elements. The bright coloration can be observed with p-polarized white light excitation, consistent with the use of this approach in display devices. The resulting color pixels are constructed with a simple design, are compatible with scalable fabrication methods, and provide contrast ratios exceeding 100:1.