In-line characterization of preamorphous implants (PAI)

Amorphous layers formed with Ge implantation into Si over a range of energy (5 to 70 keV) and dose (0.5 to 3/spl times/10/sup 15//cm/sup 2/) were characterized using carrier illumination (CI), variable angle spectroscopic ellipsometry (VASE), and cross-sectional transmission electron microscopy (XTEM). The CI signal varies lineariy with XTEM depth to 860 /spl Aring/. The VASE response is monotonic, and can be linearized with additional calibration. Both methods are sensitive to amorphous layer depth and exhibit no dose sensitivity. CI is additionally sensitive to depth differences between 0/spl deg/ to 7/spl deg/ implant angles.