AC conductivity of amorphous semiconductors

Defects in Amorphous Semiconductors: Amorphous Silicon

Defects in disordered (amorphous) semiconductors are discussed, with an emphasis on hydrogenated amorphous silicon. The general differences between defect phenomena in crystalline and amorphous hosts are described, and the special importance of the electron–phonon coupling is stressed. Detailed calculations for amorphous Si are presented using accurate first principles (density-functional) tech...

Conductivity-limiting bipolar thermal conductivity in semiconductors

Intriguing experimental results raised the question about the fundamental mechanisms governing the electron-hole coupling induced bipolar thermal conduction in semiconductors. Our combined theoretical analysis and experimental measurements show that in semiconductors bipolar thermal transport is in general a "conductivity-limiting" phenomenon, and it is thus controlled by the carrier mobility r...

Spin Injection into Amorphous Semiconductors

Conductivity in transparent oxide semiconductors.

Despite an extensive research effort for over 60 years, an understanding of the origins of conductivity in wide band gap transparent conducting oxide (TCO) semiconductors remains elusive. While TCOs have already found widespread use in device applications requiring a transparent contact, there are currently enormous efforts to (i) increase the conductivity of existing materials, (ii) identify s...

The Theory of Transport in Amorphous Semiconductors

The theory of transport in disordered systems is approached using the Master equation point of view. Emphasis is laid on a microscopic interpretation. An approximate selfconsistent theory is presented with which it is possible to evaluate hopping d.c and a.c conductivity and Hall mobility. The theory is compared with computer simulations and experiments on amorphous semiconductors. The method i...