Thermoelectric power of amorphous compound semiconductors

Hall mobility of amorphous Ge2Sb2Te5

“…Each samiple has an activation eneroy, E~, between 0.36 eV and 0.43 eV with a prefilmls. 7 WNe concur with Vander Plas and Bube in conexponential factor o0 i 10' S/cm. These observations cluding that electrical transport in these filns does not are consistent with literature values.…”

Electrical Conductivity and Thermoelectric Power of a-Se80-xGa20Tex(x=0,5,10,15 and 20) Thin Films

“…In addition to transport of holes among the extended states, small polarons near the band edges may also contribute to conductivity. These small polarons are usually associated with the structure of Se [39]. Scottmiller et al [40] have studied the effect of addition of various elements (S, Te, Bi, As, In, Ge etc.)…”

Electrical properties of amorphous chalcogenide/silicon heterojunctions modified by ion implantation

“…The total interface trap density N it (integrated across the Si band gap) was determined from the absolute difference of the flat-band voltage V fb inferred from high-frequency CV curves taken on p-and n-type Si MOS-capacitors at 77 K, as described elsewhere [12]. The dopant concentrations in the n-type and p-type silicon substrates determined after the gold electrodes and the chalcogenide films were removed by concentrated hydrofluoric acid and nitric acid were equal to 2.0+0.1x10 15 cm -3 and 5x10 15 cm -3 , respectively. The relative permittivity of the Ge-Sb-Te and Ga-La-S films required for the N it estimation and analysis of space-charge limited conduction in the amorphous chalcogenide films was calculated by using ε = n 2 -k 2 , where n and k are, respectively, the refractive index and extinction coefficient determined from spectroscopic ellipsometry data.…”

“…Qualitatively similar dependences of S for the Ge-Sb-Te and GeTe films suggest that the same processes are responsible for the observed modification of the conductivity and the change in the carrier transport mechanism. However, the resistivity of GeTe as a function of the Bi-implantation dose decreases monotonically with the implantation dose, whereas for the Ge-Sb-Te films, a non-monotonic dependence of the resistivity as a function of the implantation dose is observed, with a minimum value around 1x10 15 cm -2 , [cf. () in Fig.…”