Injection of emitted electrons in a multigrained semiconductor nanostructure

The mechanism of injection of emitted electrons into submicron grains of semiconductors has been studied by approximating their experimental current–voltage (I–V) characteristics. It is concluded that the injection in both single-crystalline and multigrained semiconductor structure can be described by the same physical model based on the notions of electron tunneling via the surface barrier and diffusion-drift transport of nonequilibrium electrons in the semiconductor. A determining role belongs to the I–V characteristic described by a power law with exponents from 2 to 4. Analysis of I–V curves allows the product of mobility and diffusion length of nonequilibrium electrons to be estimated. The obtained results can be used in the investigation and creation of multigrained semiconductor structures for gas sensors, optical sensors, and detectors and sources of infrared and terahertz radiation.