X-Ray Diffraction Measurements on Lattice Mismatch of InTlAs Grown on InAs Substrates

Abstract

InTlAs layers were grown by molecular-beam epitaxy on InAs(001) substrates, and their lattice mismatch to the substrate was characterized by X-ray diffraction measurements. In each X-ray rocking curve, a distinct peak of InTlAs was observed at a higher diffraction angle than the substrate peak, indicating a smaller lattice constant of InTlAs than InAs. The lattice mismatch, δ=(a epi-a sub)/a sub, was estimated to be -0.08% for a sample whose thallium composition x of In1-x Tl x As was determined to be 0.12(±0.02)% by Rutherford backscattering spectrometry.

Thallium incorporation during TlInAs growth by low-temperature MBE

“…More severe surface segregation than in the samples grown at 200-225 1C can be seen in both the samples grown at 250 1C. It is interesting to note here that the Tl contents around 0.1% found for the flat region in these samples grown at 250 1C are close to the Tl content obtained in our previous study [1] for the sample grown at 425 1C under a much higher BEP ratio of Tl/In.…”

“…In our previous study [1], we attempted to incorporate Tl into InAs by molecularbeam epitaxy (MBE) at moderate growth temperatures between 375 and 500 1C. It has, however, been revealed that only 0.1% mole fraction of Tl was incorporated at a growth temperature of 425 1C in spite of a large flux ratio of Tl to In [1]. On the other hand, a few published papers [2][3][4], including our previous papers [5,6], reported successful incorporation of Tl into GaAs or InGaAs up to several percent in Tl mole fraction by MBE at growth temperatures below 250 1C.…”

“…In our previous study [1], we attempted to incorporate Tl into InAs by molecularbeam epitaxy (MBE) at moderate growth temperatures between 375 and 500 1C. It has, however, been revealed that only 0.1% mole fraction of Tl was incorporated at a growth temperature of 425 1C in spite of a large flux ratio of Tl to In [1].…”

Gas Source MBE Growth and Characterization of TlInGaAs/InP DH Structures for Temperature-independent Wavelength LD Application

“…Concerning the lattice constant, Kajikawa et al [8] recently claimed that the lattice constant of TIAs is smaller than that of InAs. though the theoretical calculation by van Schilfgaade et al [9] showed the opposite result.…”

Structural and electronic properties of zincblende phase of TlxGa1−x AsyP1−y quaternary alloys: First-principles study

“…In scientific and technological areas, the interest on Thallium compounds have been ascending in recent years [5][6][7]. Especially for optical communication systems which are narrowing the band gap [8][9][10] and for heterostructure field effect transistor applications [11], Thallium compounds have been recommended as beneficial applicant. Thallium-V compounds have been indicated as an alternative to HgCdTe [12].…”