Depth profile photoemission study of thermally diffused Mn/GaAs (001) interfaces

Abstract

A study of the growth of Lu 2 O 3 on Si(001) by synchrotron radiation photoemission and transmission electron microscopy Surface electronic structure in transition-metal (Cr and Mn) doped GaAs (001) studied by in situ photoemission spectroscopy Appl.We have performed a depth profile study of thermally diffused Mn/GaAs ͑001͒ interfaces using photoemission spectroscopy combined with Ar + -ion sputtering. We found that Mn ion was thermally diffused into the deep region of the GaAs substrate and completely reacted with GaAs. In the deep region, the Mn 2p core-level and Mn 3d valence-band spectra of the Mn/GaAs ͑001͒ sample heated to 600°C were similar to those of Ga 1−x Mn x As, zinc-blend-type MnAs dots, and/or interstitial Mn in tetrahedrally coordinated by As atoms, suggesting that the Mn atoms do not form any metallic compounds but are tetrahedrally coordinated by ligand atoms, and Mn 3d states are hybridized with ligand orbitals lized but were hybridized with the electronic states of the host GaAs. Ferromagnetism was observed in the dilute Mn phase.

Thermal diffusion of Mn through GaAs overlayers on (Ga, Mn)As

“…To explain this discrepancy, we can speculate that the observed diffusion really occurred at the cleaved surface and not through the whole layer. Likewise, we must conclude that the diffusion reported between Mn and GaAs [11], where a similar band bending situation should occur, was due to ion beam related knock-in effects rather than thermal diffusion.…”

“…The inability of Mn to diffuse through GaAs has also been observed in experiments on (Ga, Mn)As capped with thin GaAs films, in which case the effect of post-growth annealing was eliminated for 10 ML thick capping [9]. On the other hand, crosssectional scanning tunneling microscopy (STM) images from (Ga, Mn)As/GaAs multilayer structures suggest that the Mn concentration in 60 ML thick GaAs spacers may be as high as 10-20% of the total Mn concentration in the (Ga, Mn)As after annealing treatment [10], and a depth profiling study of a Mn/GaAs interface indicated massive diffusion of Mn into GaAs [11]. These apparently contradictory pictures of the (Ga, Mn)As/Ga interface require further studies.…”

Solid‐state formation of ferromagnetic δ‐Mn0.6Ga0.4 thin films with high rotatable uniaxial anisotropy

“…Studies of thermodynamic stability of the Mn/GaAs(001), Mn/GaN(001), and Mn/GaP(001) thin films have shown that, with increasing annealing temperature, synthesis of Mn 2 As, MnAs, and MnP occurs and both epitaxial and polycrystalline Mn x Ga 1− x clusters are formed 12–16. The same synthesis products can be obtained via implantation of Mn ions in GaAs 17 and GaN 18, 19 substrates.…”