Scientists invent color-efficient silicon-based light-emitting diodes (LEDs)

Although silicon dominates the microelectronics and photovoltaic industries, it has long been considered unsuitable for the manufacture of light-emitting diodes. However, this is not true at the nanometer scale. Tiny silicon nanocrystals composed of hundreds of atoms can generate light and have great potential to be efficient light emitters. To date, the manufacture of silicon-based light-emitting diodes has been limited to the red visible spectral range and near-infrared rays, so the manufacture of diodes that emit colored light is absolutely novel.

KIT scientists have discovered that by using monodisperse nanoparticles of different sizes, the color of the light emitted by the diode can be changed. It can be tuned from the deep red spectral region to the orange spectral region, and the external quantum efficiency can also reach 1.1%. It is worth mentioning that the fabricated silicon-based light-emitting diodes have surprisingly long-term stability, which has never been achieved before. The increase in the life of the operating components is due to the use of only nanoparticles of the same size, which effectively enhances the stability of sensitive thin film components, while oversized particles that can cause short circuits are excluded.

This color silicon-based LED also has the advantage of not containing any heavy metals. Unlike other research groups using cadmium selenide, cadmium sulfide or lead sulfide, the silicon nanoparticles used by the research team are completely non-toxic, and the silicon on the earth is rich in reserves and low in cost, which is more conducive to the further development of silicon-based LEDs. development of.

In addition, the interesting aspect of the new type of light-emitting diode is also the homogeneity of its light-emitting area. Researchers say that as liquid-treated silicon-based light-emitting diodes can be fabricated at low cost and in large quantities, nanoparticle "groups" will also enter new fields, and the potential will be difficult to estimate, while textbooks may describe semiconductor components. It will also be rewritten.