EBIC Characterization
The EBIC technique uses the E-beam to induce a charge into a PN junction. A pre-amplifier is connected to the sample stage or a probe tip and an image is gathered through this channel as the E-beam rasters across the sample. The resulting image is then mixed with the secondary electron detector image and yields varying contrast between the P and N regions. The dopant concentration and any irregularities are now characterized.
EBAC Characterization
The EBAC technique is similar to EBIC, but is used on metal lines and buried vias. During EBAC characterization, the metal line absorbs current from the E-beam. A probe is connected to the line and again routes through a pre-amplifier to capture an image as the E-beam rasters across the sample.
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EBAC Signal mixed with SEM signal to pinpoint opens in buried metal lines. Note the sample is only de-processed to Metal 7. |
This can be done on a metal line on the surface and it will yield a quantitative active voltage contrast image. The technique is more powerful than traditional AVC, since it allows you to locate and characterize buried faults up to four layers down. A line can be contacted at metal layer 4 and an image can be captured of that same line at layer 3 and 2. The EBC Package is highly sensitive and can detect small currents from the metal line through the dielectric. By increasing the beam voltage a user can image deeper into the sample. Shorts and opens are located before destructive deprocessing eliminates the ability to detect them.
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