3D image sensing
3D sensors to revolution imaging for consumers applications
A new world of advanced human/machine interface is emerging leading to brand new applications such as augmented reality (AR), virtual reality (VR), and facial-recognition security systems.
3D cameras are the backbone of this revolution.
Challenges of CMOS Image Sensors in NIR
3D sensing techniques require specific CMOS Image Sensors (CIS) working in the Near Infrared (NIR) spectrum.
Because of the increased transparency of silicon in infrared (cf. graph on the right) there are several challenges to overcome:
1. Limited ability to capture light, resulting in reduced Quantum Efficiency (QE)
2. Increased Crosstalk
3. Increased dependence on substrate noise and metal contamination
This leads to reduced Signal to Noise Ratio (SNR)
SOI benefits for NIR CMOS image sensors
The new SOI substrate makes it possible to solve some of the challenges of NIR CIS
This optimized version of SOI substrate greatly improves the signal to noise ratio in the NIR spectrum thanks to the following key features :
1. Enhanced Quantum Efficiency thanks to light trapping
2. Reduced crosstalk thanks to complete pixel isolation
3. Total isolation through the BOX limiting the impact of substrate noise and metal contamination
4. BOX behaves also as a diffusion barrier to preventand metal contamination
Available in 300mm
BOX from 15nm to 150nm
“Epi Ready” Top silicon from 50nm to 200nm