Open AccessПрыжковая проводимость Мотта и Эфроса-Шкловского в пленках из наночастц Si, легированных фосфором и бором
Author(s) -
С.Г. Дорофеев,
Н.Н. Кононов,
С.С. Бубенов,
В.М. Попеленский,
А.А. Винокуров
Publication year - 2022
Publication title -
fizika i tehnika poluprovodnikov
Language(s) - English
Resource type - Journals
eISSN - 1726-7315
pISSN - 0015-3222
DOI - 10.21883/ftp.2022.02.51963.9727
Subject(s) - variable range hopping , materials science , conductivity , doping , electrical resistivity and conductivity , annealing (glass) , nanoparticle , fermi level , condensed matter physics , thermal conduction , analytical chemistry (journal) , electron , nanotechnology , chemistry , optoelectronics , composite material , physics , quantum mechanics , chromatography
The electrical characteristics of thin films formed from Si nanoparticles (nc-Si) with various degrees of doping are studied.To exclude the influence of ionic conductivity, the current parameters of the films were recorded in an ultrahigh vacuum (P ~ 3 – 5∙10–9 Torr) with preliminary high-temperature (9500C) annealing.An analysis of the temperature dependences of the conductivity showed that in nc-Si films formed from heavily doped nanoparticles (the concentration of free electrons ne is greater than 1019 cm-3), the transport is determined by variable-length hopping (VRH). In these samples, the Mott conductivity prevails at temperatures above 300C and at lower temperatures, the Efros-Shklovskii type variable range hopping conduction is dominate.In films with a medium level of doping of nanoparticles (ne <1019 cm-3), transport is realized by the Mott, Efros - Shklovskii and thermally activated conductivities. At the same time, thermally activated conductivity is dominated at temperatures above 560K.In nc-Si films formed from undoped nanoparticles, the transport parameters are determined by thermally activated conductivity and Mott's conductivity. Conductivity of Efros - Shklovskii is not observed in such films.From the analysis of the parameters corresponding to the Mott and Efros - Shklovsky conductivities, the localization lengths of wave functions, the density of states at the Fermi level (g (EF)), and average hopping lengths are found. The average hopping lengths in nc-Si films from nanoparticles pre-etched in HF are in the range 56 - 86 nm, which indicates that hopping in such films occurs via intermediate nanoparticles.