Some electrical characteristics of Cu- and in-doped CuInTe2

Abstract

A detailed study is made on the effects of annealing CuInTe, single crystals, both in vacuum and in the presence of elemental Cu and In. The variation of hole concentration with temperature is established and the acceptor state ionization energy is found to lie between 10 and 14 meV. This energy state is associated with the In vacancy. Mobility data are obtained and explained by taking into account various carrier scattering mechanisms including, ionized impurity, acoustic mode phonon, and space charge effects. The valence band deformation potential is found to be 5.35 eV.Une etude detaillee a et6 faite sur lee effects de recuit des cristaux simples de CuInTe, dans le vide et en presence des Blements Cu et In. La variation de concentration des trous avec la tem-p6rature a et6 etabli6 et 1'6nergie d'ionisation des 6tats de l'accepteur a ete trouvee comprise entre 10 et 14 meV. Cet &at d'bnergie, eat associ6 avec la vacance de 1'6lement In. Les donees relatives h la mobilit6 ont ete obtenub e t expliqueeS en prenant en consideration les differents mechanismes de dispersion des porteurs de charges y compris les impuretee ionishs, les phonons de mode acoutique et les effets d'bpace de charge. Le potentiel de deformation de la bande de valence est trouv6 egal a 5,35 eV. crystals, thin p-type films annealed in vacuum have been converted to n-type [lo].From electroreflectance data the band gap is reported [ll] to be 1.06 eV at 300 K and from an infrared study the effective hole masses are found to be my@, = 0.85 and mt/m, = 0.66 [12]. Some thermal and electrical properties of as-grown and l) Merida 5101, Venezuela. 3) Salford M5 4WT, England. a) On sabbatical leave at the University of Salford. 34 physic8 (a) 1112

Variable Range Hopping Conduction in p-Type CuInTe2

“…Increase of R H with 1/T confirms that in this ªhighº temperature range, conduction due to an activation mechanism is predominant, and an acceptor level around 5 to 25 meV is estimated, which agrees quite well with the reported values [10]. R H then starts to decrease after passing through the maximum as the temperature is further lowered and then remains very nearly constant.…”

Scattering of the charge carriers by ordered arrays of defect pairs in ternary chalcopyrite semiconductors

“…1 we plot for comparison the change of p with the 10 3 /T of samples of the corresponding 1:1:2 phase that have the lowest carrier concentration reported. 10,11 Their values at 300 K are also shown in Table I together with the present data. A trend that indicates the carrier concentration of these ODCs is smaller by at least two orders of magnitude is observed.…”

Transport properties of n-type CuInSe2

“…Mechanical, thermal, and electrical contacts to the samples were made by first depositing a thin film of copper by electroplating which was used as a base for soldering with pure indium. Although the instability of Cu contacts with p-type CuInSe, [16] has been reported, i.e. the electrical conductivity changes with time a t room temperature, no such effect was observed with n-type samples.…”