WORKSHOP PAPER
Optimized BSI CMOS Pixel for both UV and Visible Light
N. Fassi1,2, J.-P. Carrère1, M. Estribeau2, F. Omeis1, E. Leon Perez1, K. Jouannic1, M. Orru1, C. Augier1, T. Combier1, C. Blanc1, A.S. Sodjo1, P. Magnan2, V.Goiffon2
1STMicroelectronics, 850 rue Jean Monnet, 38926, Crolles, France
2ISAE-SUPAERO, Université de Toulouse, 10 av Edouard Belin, 31055, Toulouse, France

Abstract

This study proposes a comprehensive solution to the challenges to make a high-performance CMOS Image sensor for ultraviolet (UV) light, by utilizing backside-illuminated (BSI) CMOS image sensors with high-k antireflective coatings first demonstrated interface electrical the backside that configuration allows an excellent draining of the photo generated carriers towards the photodiode. Next, the ARC layers initially optimized for visible (VIS) light show too strong absorption into UV. Finally, a new ARC stack has been defined by optical simulation. Experimental results next demonstrate that these optimized ARC configurations enhance the sensor's Quantum Efficiency (QE) in the UV range without compromising dark current or other performance metrics, making it suitable for wide-spectrum, high-resolution imaging applications.
Year: 2025
Workshop: IISW
URL: https://doi.org/10.60928/stz5-v7tm
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Keywords

ultraviolet, backside illuminated pixels, CMOS image sensors, quantum efficiency, interface defects, antireflective coatings, high-k dielectric,

References

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