The characterization of ultrashallow junctions after implantation and subsequent rapid thermal processing (RTP) annealing is usually done in two ways. The sheet resistance of the junction is measured with a four-point probe and junction depth and dose are evaluated via secondary ion mass spectrometry (SIMS). After ultralow energy beamline implantation in a Varian VIISta 80 single wafer high current implanter the subsequent spike anneal for maximum activation and minimal diffusion was carried out on a Mattson 3000 Plus equipped with the flash-anneal controller. Junction depth profiling was done to monitor the influence of implant conditions and RTP annealing parameters. Measurements of junction depth, total dose, activated dose and uniformity were carried out on FEI Quadrupole SIMS tools. Queued measurements were performed on full wafers and small samples. Calibration of both junction depth and retained dose will be discussed. At very low beam energies (250 eV, oxygen, normal incidence) valuable information about depth profile shape, near surface concentration, and activated dose were obtained.
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