Conduction Mechanism in Amorphous As2S3

The conduction mechanism in amorphous As2S3 has been studied by investigating the variation of the electrical resistivity over the temperature range 300 – 450 K. The electrical resistivity is characterised by a mobility gap of 2.15 eV over the temperature range investigated. The dc conductivity provides evidence of conduction by excitation of charge carriers into the band  edges near the mobility edges. The results also give the possibility of conduction by a phonon-assisted hopping of polarons between localised states.Keywords: Amorphous semiconductor, hopping, mobility edg

Electrical resistivity evidence of a ferroelecteic phase transition in potassium nitrate

No Abstract. Journal of the Ghana Science Association Vol. 2 (2) 1999: pp.1-

Ferroelectricity in Sodium Nitrite Thin Films

Investigations have been conducted on the ferroelectric property of thin films of NaNO2. The thin films were prepared with the dip coating technique. The phase transition was investigated by observing the change in the dielectric constant with temperature change. The presence of ferro-electricity was investigated with a Sawyer-Tower Bridge. UV-VIS absorbance spectroscopy was used to determine the energy band gap and the extinction coefficient at room temperature. It was observed thatNaNO2 thin film undergoes a first order transition from the disordered paraelectric phase to an ordered ferroelectric phase at 162.3�C. Ferroelectricity was confirmed in the NaNO2 thin films by the appearance of a hysteresis loop below the transition temperature. The band gap of the thin film was 3.102 eV. The ferroelectric property exhibited by the NaNO2 thin films do not make it a favourable choice for modern day ferroelectric devices. However, this may be im-proved by doping the thin film with chlorine ions