A newly developed chemical bevelling technique used for depth independent high depth resolution SIMS analysis

Abstract

A newly developed chemical bevelling technique has been used to produce bevelled samples for secondary ion mass spectrometry (SIMS) studies. A linear bevel with an abrupt surface/bevel interface was produced for the first time in chemical bevelling by adding a layer of oil on top of NH 4OH H 2O 2 etching solution. A series of bevel magnifications ranging from 5 × 10 2to 6 × 10 3 were obtained by changing the concentration of the etching solution. Al ion implanted GaAs and Al 0.3Ga 0.7As GaAs multi- quantum well samples were chemically bevelled and investigated using SIMS linescan profiling. A typical Al implant linescan profile was obtained and its accuracy was comparable to that achieved by depth profiling. Results from Al 0.3Ga 0.7As GaAs MQWs showed a high depth resolution of 3.1 nm retainable through the structure to at least 1.6 μm beneath the original surface. The relationship between depth resolution and the ion beam energy was studied.