Depth resolution function of the laser assisted tomographic atom probe in the investigation of semiconductors

The investigation of boron delta layers by tomographic atom probe (3DAP) is used to demonstrate that a depth profiling resolution of 0.9 nm (full width at half maximum) can be achieved. Results are compared with measurements provided by secondary ion mass spectrometry. The steepness is found to be below 1 nm/decade. In addition, silicon atomic planes are resolved in the real space demonstrating an in-depth spatial resolution of the 3DAP below 0.2 nm.