The Sio <sub> 2 </ Sub> / Si (001) Surface Of Er-related Nanostructures And Their Photoluminescence Properties, And

Considerable methods have been used to develop an efficient Si-based light-emitting material,with a wavelength～1.5μm,due to the potential application in optoelectronic.However,the ever increasing optical information traffic is demanding broadband Si-based light emitting diodes beyond the conventional 1.5μm window, for integration with the all-wave fiber communication systems and to fully utilize the 1.280μm to 1.625μm low-loss bands.In order to realize the tunable or continuous broadband luminescence,we attempt to put the efficient optically-active Er³⁺ ions and the defect related luminescence(DRL) centers into Si by introducing many dislocations in the growth process of Er-related nanostructures on Si(001).To improve luminescent efficiency of Er³⁺ ions,an ultrathin SiO₂ film is grown on the Si(001) surface to achieve the even distribution of Er atoms and the formation of optically-active Er-O complex.Er-related nanostructures self-assembled on the Si(001) covered with an ultrathin SiO₂ layer have been studied by scanning tunneling microscopy and photoluminescence(PL),compared with Er-related nanostructures formed on clean Si(001).The post-annealing temperature of 560℃-660℃can lead to the formation of Er silicate nanobunches,with an ultrahigh density of 1×10¹²-1×10¹³ cm^-2.The Er silicide nanowires are obtained at the post-annealing temperature above 700℃. Er-related nanostructures will change from the amorphous nanobunches to the crystalline nanowires with the increase of post-annealing temperature due to the SiO desorption.The PL band shape and intensity depend strongly upon the preparation conditions and a wide band is exhibited from 1.3μm to 1.6μm due to DRL and Er³⁺ ion.A dominant peak at 0.80 eV is observed for the nanobunches.We have distinguished the Er³⁺ line from the D1 line,which have the same energy region around 0.80 eV,and it is shown that our samples have effective optically-active Er³⁺ ions.