Photoluminescence performance of pulsed-laser deposited Al2O3 thin films with large erbium concentrations

Erbium doped Al2O3 films with concentrations up to 6x10(20) Er cm(-3) have been prepared in a single step process by pulsed-laser deposition. Alternat e ablation of Al2O3 and Er targets has been used to control the in-depth di stribution and in-plane concentration of Er3+ ions independently. The chara cteristic Er3+ photoluminescence response at 1.53 mum has been studied as a function of the Er3+ distribution. It is found that lifetime values can be greatly increased by increasing the Er3+-Er3+ in-depth separation above 3 nm. This result can be related to a reduced Er3+-Er3+ energy migration proc ess. The in-plane Er3+ concentration was increased by either increasing the number of pulses on the Er target or the laser energy density for ablation . By the latter method in-plane concentrations as high as 1.1x10(14) Er cm( -2) per layer (corresponding to 2x10(20) Er cm(-3)) were achieved, while ke eping lifetime values as high as 6 ms. This result is explained in terms of shallow Er3+ implantation during deposition. (C) 2001 American Institute o f Physics.