Effect of phosphorus on electrical properties of undoped InP grown at low temperature by atomic layer molecular beam epitaxy

摘要

Undoped InP layers grown at low temperature by atomic layer molecular beam epitaxy have been studied by Hall measurements and deep level transient spectroscopy. The free carrier concentration at room temperature increases linearly with phosphorus pressure and it has been possible to obtain layers with a free carrier concentration of 1 × 1016 cm-3 and an electron mobility of about 3000 cm2 V-1 s-1, which are similar to values for samples grown at high temperatures. Deep level transient spectroscopy shows the presence, in all the samples, of five electron traps with emission energies of 0·60, 0·40, 0·25, 0·16, and 0·11 eV from the conduction band, with concentrations independent of the free carrier concentration with the exception of the 0·40 eV trap concentration, which increases slightly with free carrier concentration. © 1996 The Institute of Materials.