Properties of II–VI semiconductors associated with moving dislocations

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“…The average charge density was found to be close to -2← → 10 −10 Cm −1 for the dislocation bands predominantly consisting of S(g) dislocations and +1← →10 −10 Cm −1 for the dislocation bands predominantly consisting of Zn(g) dislocations, respectively. The former charge density is similar to the value of -3← →10 −10 Cm −1 found by Petrenko and Whitworth (1980) on moving S(g) dislocations in ZnS using the method of dislocation currents (Osip'yan et al 1986). Thus, the electric charges of resting Zn and S dislocations were determined quantitatively for the first time.…”

“…The primary slip system is <110>{111} and the Burgers' vectors of perfect dislocations are a/2<110> (Holt 1962). The moving dislocations in the ZnS are Shockley partials with Burgers' vectors of a/6 <112> (Zaretskii et al 1983), which have a component of to along [110], and they move on the planes of the glide set (Osip'yan et al 1986). Another important feature of the sphalerite structure of ZnS is that dislocations with an edge component can be of two kinds, depending on whether the extra half-plane terminates in a row of metal or nonmetal atoms (Haasen 1957).…”

“…Cleaved fresh, clean, atomically smooth, and dislocation-free (110) ZnS surfaces were obtained by using a razor edge in air. Knowing the geometry of the slip bands, the technique of dislocation current (Osip'yan et al 1986) was used to determine the absolute orientation of the specimen. By this method, one simply measures the current when the ZnS crystal is deformed as shown schematically in Figure 1.…”

“…First, dislocations can be produced during fabrication of integrated circuits due to the enormous elastic stresses that build up, (e.g., during formation of shallow isolation trenches (Fahey et al 1992). Second, dislocations are so mobile at room temperature that they can easily multiply during the operation of optoelectronic devices due to temperature gradients and electric fields (Osip'yan et al 1986).…”

“…23, 3 (2001) The dislocation density, ρ d (x,y) was calculated from the topographic data z (x,y) using (5) where b z is the component of the Burgers' vector along the z direction of [110] and ρ d (x,y) is the density of dislocations. Since perfect dislocations of a/2<110> are never observed in ZnS (Osip'yan et al 1986), here we used a Burgers' vector of a/6 <112> for isolated 30˚ partial dislocations. The results are shown in Figure 6c for the scratching trench along [111] and in Figure 6d for the scratching trench along [111].…”