Investigations of nano size defects in InP induced by swift iron ions

Indium phosphide (InP) samples were irradiated with swift (100 MeV) 56Fe7+ ions with different fluences varying from 5 × 1012 to 2 × 1014 cm−2 at room temperature. Atomic force microscopy (AFM) and high resolution X-ray diffraction (HRXRD) have been used to investigate the irradiation effects. AFM observations revealed the presence of nanosized defect clusters in all irradiated InP samples. Size (diameter) and density of defect clusters was found as a function of ion fluence. Root mean square (r.m.s) surface roughnesses measured using the Nanoscope software supplied with the AFM instrument were found to change from 0.33 nm to 7.49 nm. HRXRD studies revealed the presence of radiation-damaged layer (strained peak) in high fluence (2 × 1014 cm−2) Fe ion irradiated InP. The screw dislocations, out of plane strain and lattice mismatch of irradiated samples have been studied.