Process control of CMOS image sensor arrays
As imaging technology has improved, the challenges related to manufacturing those devices has increased. Smaller, physical pixel size, larger array areas, better quantum efficiency all present challenges for process control of this critical area. Color photo resist ADI profile, deep trench isolation etch profile and back-end metal CMP all need to be accurately controlled to enable super low noise sensing with minimal cross-talk. Additionally, the ability to find sub-micron defects as well as macro-level variations within the array is important to ensure consistent response throughout the array area.
Onto Innovation enables accurate measurement and control of deep photo resist and Si channel profile/deptch for pixel isolution, as well as CMP thickness and dishing to ensure device yield. Our inspection systems control for the array area with unique image processing, creative illumination and high resolution to ensure device yield.