Analysis of 5keV Boron implants with the CAMECA Shalllow Probe
The CAMECA Shallow Probe goes beyond standard implant metrology: based on the LEXES technique, the analyzed signal is proportional to the dose of the investigated species. Not only implants can be analyzed, but also and simultaneously, cross-implants, contamination, SiO2 top layer, B and even F in case of BF2/BF3 implantation.
Another interesting feature is the capability to measure BOTH as-implanted and annealed wafers, allowing engineers to control their process at any time.
121-point mapping on USJ Boron implanted at 5keV
Courtesy of LETI, France. This example shows 121-point mappings of USJ Boron implanted at 5keV on as-implanted and annealed 300mm wafers.
Repeatability on B dose measurements is better than 0.5% for both as-implanted and annealed wafers. The average dose is 1.92 e15 at/cm2 for as-implanted, and 2.14 e15 at/cm2 for annealed. The screen oxide is removed in both cases but only after anneal for the annealed wafer. The dose increase after anneal indicates B migration from screen oxide to bulk during anneal.
The ideal metrology tool for ultra shallow implants
The above example shows results for 5keV Boron implants. However, as it is based on LEXES, a specialized EPMA technique for the analysis of thin layers and shallow implants, the Shallow Probe is optimized to analyze even shallower implants at energies < 5keV.
Full flexibility for wafer mapping and pattern analysis
A mapping of 121 points is shown here, but users have full choice as to the number of points to be analyzed in the specified zone. Small mapping in dedicated areas and pads is possible. Pads as small as 50x50µm can be monitored.