Bond rupture of threefold-coordinated Si atoms at intrinsic sites on the Si(111)-(2×1) induced by 1.16-eV photon excitation

Excitation-induced germanium quantum dot formation on Si(100)-(2×1)

“…25,26 Although the Si͑100͒-͑2 ϫ 1͒ surface has surface specific optical transitions, their contribution is small for excitation with 1064 nm wavelength. 7 Due to the low surface absorption coefficient ͑␣ =11 cm −1 ͒ of the 1064 nm radiation in Si, photoexcitation takes place mainly in the bulk. Therefore, the primary effect of the 1064 nm nanosecond laser light on the Si substrate is bulk-valence excitation to generate holes and electrons with small excess energies.…”

“…Preferential bond rupture nearest to pre-existing vacancies was also observed on the Si͑111͒ surface. 6,7 Selective removal of the topmost layer was also shown for Si͑100͒-͑2 ϫ 1͒. 46 In this case, localized electronic states at defects, such as vacancies, on the reconstructed surface are believed to be responsible for this selective layer removal.…”

“…42 THL on surface sites of nonequilibrated valence holes was concluded to be the mechanism responsible for bond breaking when a Si͑111͒-͑2 ϫ 1͒ surface was excited by 1064 nm, 3.5 ns laser pulses. 39 Surface bond rupture rate was studied for Si͑111͒, 3,7,24,39 Si͑100͒, 41,43,44 and other materials. 3 The rate of bond rupture varies between 3 ϫ 10 −5 and 8 ϫ 10 −10 ML/ pulse depending on the laser wavelength and fluence.…”

“…[2][3][4][5] Recent scanning tunneling microscopy studies have demonstrated that laser pulses well below the melt and ablation thresholds induce bond rupture at individual atomic sites on several semiconductor surfaces via a process that is purely electronic. [6][7][8] The laser-induced electronic bond rupture causes structural changes on the surface which depend strongly on the surface studied.…”

Role of two-hole localization in anion-vacancy formation on the (110) surfaces of InP and GaAs at the third regime of Langmuir evaporation

“…[6][7][8][9][10] This feature implies that non-linear interactions of photogenerated carriers or excitons are crucial for generating vacancies on semiconductor surfaces. The THL mechanism formulated by Sumi 5 has described satisfactorily the nonlinear characteristic of the formation of surface vacancies.…”