Omnivision BSI pixel uses P+ backside implant to passivate the backside surface. The recently published WO/2009/099491 patent application gives some details of its optimization process. The figure below shows the location of the backside P+ implant 220:
First, Omnivision optimizes the P+ layer depth, making few implants with different energies:
The sensitivity for the different depths is shown below:
Next step is the optimization of the P+ implant dosage. The three tested dosages are shown here:
The pixel sensitivity vs dosage is shown below:
One more step is optimization of the silicon layer thickness:
First, Omnivision optimizes the P+ layer depth, making few implants with different energies:
Next step is the optimization of the P+ implant dosage. The three tested dosages are shown here:
The pixel sensitivity vs dosage is shown below:
Omnivision BSI Backside Implant Optimizations
Reviewed by MCH
on
October 11, 2009
Rating:
Reviewed by MCH
on
October 11, 2009
Rating:
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