High-resolution and high-efficiency microdisplays are critical components of wearable electronics – such as smart glasses – but developing a low-power, high-brightness pixel technology has proven difficult. A liquid-crystal on silicon (LCoS) display, for example, requires an external light source that constantly draws significant current, whereas a micro-organic-light-emitting-diode (μ-OLED) display offers better power efficiency, but its brightness and lifetime are low. The Nano-Eclipse LED (N-LED) is expected to draw significantly less power than current microdisplays – potentially doubling battery life – while also offering higher brightness, contrast, and resolution. N-LEDs also have a low material cost compared to traditional LEDs, and they can be scaled down to the nanometer range.

Technology Description

The N-LED consists of five layers: a silicon-based electron supply layer, a quantum-dot emissive layer, a polymer hole layer, and an anode layer. When voltage is applied to the supply layer, a dense electron gas is formed at the junction with the next layer. The electrons repel each other and are injected strongly to the next layer above. The turn-on voltage required to achieve bright illumination is very low (~1-2V), and because illumination is greatest at the periphery of each emitter, efficiency improves as size shrinks, making this system ultimately scalable. Nanometer-sized perforations can be achieved right now using electron beam lithography, and ultimately we expect to generate sub-nanometer LEDs containing a single quantum dot. This technology can be used as a silicon-based single-photon source on demand, which will be important for future quantum information technology.

Advantages

  • Lower power consumption than current microdisplay technology
  • Low material cost
  • High brightness, color contrast, and resolution
  • Long lifespan
  • Scalable to nanometer range
  • Integrable to electronic chips

Applications

  • Near-eye displays (e.g., camera viewfinders, head-mounted displays, and smart glasses)
  • Quantum computing

IP Status

An US patent 9,331,189 was issued May, 2016. Divisional patent application 15/067,272 was filed March, 2016. A provisional US patent application was filed May, 2017.

Stage of Development

We have demonstrated light emission and confirmed low voltage operation. Currently, we are optimizing hole-spacing and the charge-conducting layer to achieve theoretical efficiency.

Notable Mentions

  • The Chancellor’s Innovation Commercialization Funds ($35,000)
  • Pitt Ventures First Gear ($3,000)