Friday, May 29, 2009

Chipworks Reveals Sony BSI Secrets

Semiconducor International publishes Chipworks' Ray Fontain's article on Sony BSI sensor reverse engineering findings. The article reveals:

  • Sony BSI uses SOI process - meaning it's not cheap.
  • The sensor's backside has AR layer
  • The backside uses aperture grid made of tungsten
  • Assuming the pixel size of 1.75um, the silicon layer thickness is about 2.8um
  • It appears there is 0.8-0.9um thick spacer between microlens and color filter, so the distanse from microlens to the silicon surface is about 2um

    The picture below shows the sensor cross-section:


Update: It appears that Sony uses an additional conforming AR layer on top of microlens (should I say on bottom of microlens?).

2 comments:

  1. Hi,

    I was poking around ST's website and came across a new image sensor roadmap in their May 15 analyst presentations (slide 9):

    http://services.choruscall.com.att-idns.net/lugano/stm090515/4_technology_manufacturing.pdf

    Regards,

    Dick James

    ReplyDelete
  2. Dick,

    Many thanks for the interesting link! I'm re-posting this to the front page.

    ReplyDelete

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