A Deep Dive into High-Performance Electron Injection Material

Commercial photonics have been subject to radical change in a relatively short period. Our understanding of how to generate high fidelity light waves efficiently and reliably has coincided with a revolution in nanomaterial synthesis. This is best exemplified by the onset of high-performance electron injection materials.

The Basics of Electron Injection Materials

Light can be generated using a wide range of phenomena. Two household examples of this include:

  • Incandescence: A current is passed through a thin tungsten coil, causing it to heat up to the point of glowing. Incandescent lighting is largely obsolete owing to its poor efficiencies: as little as 5% of the energy used is converted into light.
  • Fluorescence: A current is passed through a vapor that emits shortwave ultraviolet (UV) radiation when excited. This impinges on a phosphorous coating on the bulb which subsequently glows. Though more efficient than incandescent bulbs, fluorescent lights are undesirable as they contain hazardous materials.
  • Electroluminescence: A voltage is applied to a semiconducting material which emits light when a current is flowing through it. Electroluminescent light sources like light-emitting diodes (LEDs) are now the gold standard for efficient lighting.

Electroluminescence provides the basic mechanism of illumination in modern consumer displays and smart devices. It results from the recombination of electrons and holes in a solid-state device. Most high-performance semiconducting arrays comprise a stack of semiconducting materials that selectively block/transmit either electrons/holes. These distinct thin-film transistors (TFTs) are typically based on silicon or novel metal oxide materials capable of facilitating efficient electron transportation through the stack.

High-performance electron injection materials are typically formatted as solutions containing metal oxide nanoparticles with the optimal conductivity and work function for specific applications. Their primary purpose is to emit electrons from one solid into another. In a standard p-n thin film, the n-type semiconductor injects electrons through the junction where they recombine with electron holes. This is more complex in modern thin film devices composed of multiple tandem semiconducting elements deposited onto electrical elements like silver nanowires and Perovskite absorbers.

High-Performance Injection Electron Materials from Avantama

At Avantama, we have developed a broad variety of off-the-shelf nanoparticle formulations for a range of photonics applications, including premium OLED and QLED displays and emerging lighting solutions. Our primary high-performance electron injection material comprises zinc oxide (ZnO) nanoparticles centred around a mean particle size of 12 nanometres (nm). This low work function electron injection formulation has a concentration of 2.5% solids loading (WT%) in a mixture of alcohols and is compatible with a wide spectrum of deposition techniques, including spin and slot die coating.

N-11 is our standard high-performance electron injection material, providing manufacturers with a scalable formulation for precision light emitting applications. If you would like more information on the features of our high-performance electron injection material, or need something more specific for your workflow, simply contact a member of the team today.