Some Properties of In[sub 2]Te[sub 3] and Ga[sub 2]Te[sub 3]

Abstract

This paper summarizes the measurements which have been made to determine various physical parameters for the compounds Ga2Te3 and In2Te3 . The previously described problems of the preparation of stoichiometric In2Te3 and Ga2Te3 and the associated question of ordering of lattice vacancies in In2Te3 are reviewed briefly. Measurements of the thermal coefficient of expansion of the two compounds at liquid air and room temperatures are described. The main section of the work concerns the measurements of electrical conductivity and Hall effect in the compounds. The determination of activation energy values from the electrical measurements and their relation to the energy gap is discussed, and values of activation energies and also of electron mobilities are given for ordered and disordered In2Te3 . It is shown that the change in activation energy in In2Te3 at 470°C is not associated with a change in structure, and an explanation in terms of change in conduction band minimum is considered. Results of preliminary room temperature measurements of thermal conductivity in Ga2Te3 and ordered In2Te3 are given.

Semiconducting Properties of AgIn[sub 3]Te[sub 5]

“…The thermal conductivity of AgInsTes, 0.009 w/ cm~ is essentially the same as that of ordered InfTe3, 0.011 w/cm~ reported by Zaslavskii (14). However, Gasson et al (13) have reported the thermal conductivity of InfTe3 as 0.008 w/cm~ whereas Wooley and Pamplin (15) have reported a value of 0.014 w/cm~ These values are indicative that more definitive work remains to be done on InfTe3 as discussed by O'Kane and Mason (16).…”

Semiconducting Properties of Peritectic Compounds from the Pseudo-binary System of CdTe-In[sub 2]Te[sub 3]

“…However there is considerable discrepancy in the reported values for the energy gap of disordered In2Te3. Although Zhuze et al (13) report an energy gap of 1.12 ev for disordered In2Te3, and Gasson et al (14) report that Eg = 1.02 ev, Woolley and Pamplin (15) report that Eg ----1.55 -----0.05 ev, and Appel (16) reports that Eg for disordered In2Te3 is equal to 2.4 • 0.1 ev. These latter results along with preliminary unpublished work in our laboratory suggest that Zhuze et al (13), Gasson et al (14), and perhaps even Woolley and Pamplin (15) were not observing an energy gap characteristic of pure, uncontaminated disordered In2Te3.…”

On the phase diagram of the Ga-Te system in the composition range 55 at % Te

“…1): (a) Ga-Te (64.65 wt% Te), with two structural modifications, a monoclinic [3][4][5][6][7][8] and an hexagonal structure [4] and (b) Ga2Te3 (73.30wt % Te), with an fcc zinc blende structure [1][2][3][4]9,10]. An orthorhombic superstructure is also reported [11 ].…”