The Effect of Doping on the Electrophysical Properties of Polycrystalline Diamond Films Deposited from an Abnormal Glow Discharge

The paper is focused on the study of the boron doping effect on the electrical characteristics, on the mechanism of charge carrier transfer, and on the energy spectrum of the localized defect states in the polycrystalline diamond films (PDF) deposited from an abnormal glow discharge. PDF doping enables to form the semiconductor layers of p-type conductivity, which have as good properties as those of PDF produced by the alternative methods. The doping reduces the degree of disorder in the film material brought by the growth defects, which determine the film electrical characteristics and electrotransfer mechanism. The PDF electrical characteristics and electrotransfer mechanism are determined by the defects of different nature, whose band gap energy levels have a continuous energy distribution. A p-type activation component is realized in the exchange of charge carriers between the valence band and shallow acceptor levels with the activation energy of 0.013-0.022 eV. Doping increases the effect of the hopping mechanism of the conductivity involving the localized states with a density of (1-6)•10{20} eV{-1}•cm{-3} distributed near the Fermi level, which is in the low half of the band gap

Urbach's rule criteria in alumina irradiated with ions

Irradiation of dielectrics with ions is available for aims of the optical, mechanical and other properties modification. The defect localized states effect on alumina optical absorption properties depends on ability of incorporated elements to substitute the lattice cations. The complex energetic spectrum of the defect localized states demands the generalized approaches which characterize the radiation induced disorder in materials as a whole. The Urbach's rule criteria for the absorption spectra of alumina irradiated with the silicon, chromium and titanium ions (Ф=10^17 cm^-2, E2=100 keV) were investigated. The induced defect, their clusters and hard solid solution effect on the Urbach's equation parameters was determined. Analysis the reasons of the absorption change was given. Absorption spectra of irradiated alumina were subjected the Urbach's rule as all it criteria were fulfilled. This is stipulated by the static disorder in crystalline lattice induced by substitution defects, intrinsic defects and cluster formation on its base. A common focal point in absorption spectrums situated at 4.4 eV was fixed. This Urbach's focus is determine by the processes of defects clusterization, the energetic characteristics of clusters and depend on ability of the implanted ions to form the hard solid solutions in alumina. A correlation between the interband and exponential absorption parameters indicates to synthesis in Аl2Оз a new strongly defect material having band gap width near the 4.5 eV and absorption edge stipulated by the defect cluster levels

Ion-heat modification of inorganic dielectrics properties

The influence of an ions irradiation and subsequent annealing in vacuum on mechanical and electrophysical properties of irganic dielectrics examined. The opportunity of purposeful regulation of their surface resistivity in limits 10 ..10 Ohm per squ (П/П) is shown. The modes of modification ensuring deriving on a surface of dielectrics a thermostable resistive coatings are giv

Ion-heat modification of inorganic dielectrics properties

The influence of an ions irradiation and subsequent annealing in vacuum on mechanical and electrophysical properties of irganic dielectrics examined. The opportunity of purposeful regulation of their surface resistivity in limits 10 ..10 Ohm per squ (П/П) is shown. The modes of modification ensuring deriving on a surface of dielectrics a thermostable resistive coatings are giv

Urbach's rule criteria in alumina irradiated with ions

Irradiation of dielectrics with ions is available for aims of the optical, mechanical and other properties modification. The defect localized states effect on alumina optical absorption properties depends on ability of incorporated elements to substitute the lattice cations. The complex energetic spectrum of the defect localized states demands the generalized approaches which characterize the radiation induced disorder in materials as a whole. The Urbach's rule criteria for the absorption spectra of alumina irradiated with the silicon, chromium and titanium ions (Ф=10^17 cm^-2, E2=100 keV) were investigated. The induced defect, their clusters and hard solid solution effect on the Urbach's equation parameters was determined. Analysis the reasons of the absorption change was given. Absorption spectra of irradiated alumina were subjected the Urbach's rule as all it criteria were fulfilled. This is stipulated by the static disorder in crystalline lattice induced by substitution defects, intrinsic defects and cluster formation on its base. A common focal point in absorption spectrums situated at 4.4 eV was fixed. This Urbach's focus is determine by the processes of defects clusterization, the energetic characteristics of clusters and depend on ability of the implanted ions to form the hard solid solutions in alumina. A correlation between the interband and exponential absorption parameters indicates to synthesis in Аl2Оз a new strongly defect material having band gap width near the 4.5 eV and absorption edge stipulated by the defect cluster levels