The polaron and bipolaron assisted charge transport in polyaniline induce a motion of hole in the polyaniline and p-type conductivity
is achieved [44-47].
Conibeer, "Surface states induced high P-type conductivity
in nanostructured thin film composed of Ge nanocrystals in Si[O.sub.2] matrix," Applied Physics Letters, vol.
[Cu.sub.2]O prepared by thermal oxidation or by physical vapor deposition usually contains copper vacancy ([V.sub.Cu]) defects with a carrier density as high as [10.sup.18] [cm.sup.-3] that results in its p-type conductivity
Copper based delafossite materials have resolved this problem as these materials have high p-type conductivity
and tune-able optical band-gap.
The very impressive aspect of this study was the wide range of temperature and the repetitive consistency with which p-type conductivity
Krost, "Local p-type conductivity
in zinc oxide dual-doped with nitrogen and arsenic," Applied Physics Letters, vol.
"The purpose of the research is to introduce a pollutant that switches the conductivity of zinc oxide from N to P under the determined laboratory conditions, and makes possible the production of electronic pieces only from transparent conductors such as zinc oxide which are mostly known as transparent electrodes," Siyamak Golshahi, one of the researchers at Gilan University, told INIC."Spray pyrolysis method was used to accumulate zinc oxide layers in order to pollute them and to obtain P-type conductivity
," Golshani said, adding, "In this method, which is usually classified in chemical accumulation methods, raw materials (salts which contain final elements) are dissolved in solvents such as methanol, ethanol, water, etc, and constitute the initial material.
Due to the formation of Cd vacancies in CdTe lattice acting as acceptor centers, CdTe films prepared by different techniques have generally high electrical resistivity ([10.sup.7-[10.sup.9] [ohm]cm), and with slightly p-type conductivity
, on the other hand, an excess of Cd atoms located interstitially can produce n-type CdTe samples.
The origin of p-type conductivity
in these transparent oxides receives considerable attention, and field emission properties and nanostructured materials are discussed.
Sn[O.sub.2] is generally an n-type semiconductor due to the existence of intrinsic defects such as oxygen deficiencies and tin interstitials; but, SnO exhibits p-type conductivity
and relatively high hole mobility originated from the tin vacancy.
They find that it is p-type conductivity
, and the acceptor ionization energy is about 196 meV, which is larger than the calculated results of 155 meV by Gai et al.