Phase equilibria and liquid-phase-epitaxy growth of PbSnSeTe lattice-matched to PbSe

Abstract

The phase equilibria data necessary for growing solid compounds of Pb1−xsSnxsSe1−ys Teys lattice matched to PbSe from melts consisting of (Pb1−xLSnxL)1−z (Se1−yLTeyL)z are presented. Liquidus data for values of xL from 0% to 40% and yL from 0% to 40% for temperatures between 450 and 540 °C are also presented. The influence of tellurium on the liquidus temperature is shown to be negligible at least for yL less than 40%. A crossover in the liquid-solid tie lines of tin, xs vs xL, for layers grown at 650 and 450 °C is observed at xL equal to 14%. The liquid-solid tie-line data for tellurium, ys vs yL, show a low segregation coefficient relative to selenium for yL less than 40%, thus explaining tellurium’s limited influence on the liquidus temperature. The lattice-matching conditions for xL =5%, 10%, and 20% are yL =16.4%, 25%, and 33.5%, respectively. A significant lattice-pulling effect is observed for the 5% tin case and is expected for the 10% and 20% tin cases. This effect, along with the low relative segregation coefficient for tellurium, makes it possible to easily grow lattice-matched layers of PbSnSeTe on PbSe by liquid phase epitaxy.

Molecular beam epitaxy of PbSrSe and PbSe/PbSrSe multiple quantum well structures for use in midinfrared light emitting devices

“…8 The corresponding Sr to PbSe flux ratios used to adjust the Sr composition during the growth are also listed in Table I for reference. Figure 2 shows the FTIR transmission spectra for two PbSrSe samples with Sr compositions of 0.068 and 0.230, respectively.…”

The Effect of Composition Dependent Lattice Strain on the Chemical Potential of Tellurium in Pb1−xSnxSe1−yTey Quaternary Alloys

“…Values for the tellurium content in the solid, ys, were then calculated using an equation derived from Vegard's law for quaternary alloys that are lattice matched with BaF 2 [2]: 0.074 + 0.1 2 3xs This method of calculating PbjxsSnxsSejysTeys solid composition assumes that the liquidsolid segregation coefficients for the metal, Pb and Sn, and non-metal, Se and Te, atoms are independent. This assumption is valid based upon comparisons of x-ray and Auger electron spectroscopic determined compositions of Pbi~xsSnxsSelysTeys quaternary alloys grown on PbSe [3]. Work by Davarshvili et al [2] also confirms that the composition of the metal sublattice is independent of the tellurium content in the liquid growth solution.…”

“…Table I summarizes these data and also lists values for tin and tellurium content in PbIxsSnxsSeiysTeys solid alloys that are lattice matched with BaF 2 . Values for the tin content in the solid, xs, were determined explicitly from x-ray diffraction analysis of LPE-grown PblxsSnxsSe ternary layers on PbSe substrates [3]. Values for the tellurium content in the solid, ys, were then calculated using an equation derived from Vegard's law for quaternary alloys that are lattice matched with BaF 2 [2]: 0.074 + 0.1 2 3xs This method of calculating PbjxsSnxsSejysTeys solid composition assumes that the liquidsolid segregation coefficients for the metal, Pb and Sn, and non-metal, Se and Te, atoms are independent.…”

“…EXPERIMENTAL PROCEDURE (Pb1..xSnxl)o.9 9 (Se1.y 1 Tey,)o.oi growth solutions were prepared using weighed portions of six nines lead and tin and polycrystalline pieces of PbTe and PbSe. With a chalcogen content fixed at 1%, the liquidus temperatures for these solutions were in the range of 530 0 C [3]. Pbl.xsSnxsSe_yjTeys solid solution alloys were grown from these liquid solutions on freshly cleaved (111 )-oriented BaF 2 substrates using a standard sliding-substrate LPE graphite boat under a flowing hydrogen ambient.…”

“…Substrates for lattice-matched layer growth include Pbo. 80 Sno.2oTe [1], PbSe [2, 3], and KCI [4]. The growth method in all of these cases has been liquid phase epitaxy (LPE).…”