Abstract:
Determination of density of states of hydrogenated amorphous siliconby phase shift analysis of modulated photocurrent.Determination of the energetic distribution of localized statesdue to random network and structural defects within the mobility gap of amorphous semi conductorsis of great importance for understanding the transport properties of these materials. Since there is no structural order,the band states can be only determined experimentally.In this thesis, the density of states (DOS) distribution in the energy gapof Hydrogenated n-type amorphous silicon is determined. For this purpose a The Phase shift analysis of modulated photocurrent (PSAMP) method is studied. The validity of the PSAMP theorem for the doped a-H:Si is discussed. The theorem is verified for this type of semiconductors and the distribution of the states is determined for a range of 400 meV.
