Abstract

Recently, the on-chip autofocus (AF) function has become essential to the CMOS image sensor. An auto-focus usually operates using phase detection of the photocurrent difference from a pair of AF pixels that have focused or defocused. However, the phase-detection method requires a pair of AF pixels for comparison of readout. Therefore, the pixel variation may reduce AF performance. In this paper, we propose a color-selective AF pixel with a plasmonic nanostructure in a 0.9 µm2 pixel. The suggested AF pixel requires one pixel for AF function. The plasmonic nanostructure uses metal-insulator-metal (MIM) stack arrays instead of a color filter (CF). The color filters are formed at the subwavelength, and they transmit the specific wavelength of light according to the stack period and incident angles. For the optical analysis of the pixel, a finite-difference time-domain (FDTD) simulation was conducted. The analysis showed that the MIM stack arrays in the pixels perform as an AF pixel. As the primary metric of AF performance, the resulting AF contrasts are 1.8 for the red pixels, 1.6 for green, and 1.5 blue. Based on the simulation results, we confirmed the autofocusing performance of the MIM stack arrays.

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  1. S. UchiyamaSuperiority of image plane phase detection AFJ-Stage, Japan, ITE Technical Report2012Sep.2136[Online]. Available: https://www.jstage.jst.go.jp/article/itetr/36.38/0/36.38_17/_article/-char/en
  2. H. Endo"Phase detection pixel built-in image sensor" to realize high speed auto focusJ. Inst. Image Inf. Telev. Eng.201165290292
  3. M. Kobayashi, M. Johnson, Y. Wada, H. Tsuboi, H. Takada, K. Togo, T. Kishi, H. Takahashi, T. Ichikawa, and S. InoueA low noise and high sensitivity image sensor with imaging and phase-difference detection AF in all pixelsITE Trans. Media Technol. Appl.20164123128
  4. A. Morimitsu, I. Hirota, S. Yokogawa, I. Ohdaira, M. Matsumura, H. Takahashi, T. Yamazaki, H. Oyaizu, Y. Incesu, M. Atif, and Y. NittaA 4M pixel full-PDAF CMOS image sensor with 1.58 µm 2×1 On-Chip Micro-Split-Lens technologyITE Tech. Rep.20153958
  5. S. Choi, K. Lee, J. Yun, S. Choi, S. Lee, J. Park, E. Shim, J. Pyo, B. Kim, M. Jung, Y. Lee, K. Son, S. Jung, T. Wang, Y. Choi, D. Min, J. Im, C. Moon, D. Lee, and D. ChangAn all pixel PDAF CMOS image sensor with 0.64 µm × 1.28 µm photodiode separated by self-aligned in-pixel deep trench isolation for high AF performanceProc. Symposium on VLSI TechnologyKyoto, Japan2017Jun.T104T105
  6. T. Okawa, S. Ooki, H. Yamajo, M. Kawada, M. Tachi, K. Goi, T. Yamasaki, H. Iwashita, M. Nakamizo, T. Ogasahara, Y. Kitano, and K. TataniA 1/2 inch 48M all PDAF CMOS image sensor using 0.8 µm Quad Bayer Coding 2 × 2OCL with 1.0 lux minimum AF illuminance levelProc. IEEE International Electron Devices Meeting (IEDM)San Francisco, CA, USA2019Dec.16.3.116.3.4
  7. D. N. Yaung, B. C. Hsieh, C. C. Wang, J. C. Liu, T. J. Wang, W. D. Wang, C. C. Chuang, C. Chao, Y. L. Tu, C. S. Tsai, T. L. Hsu, F. Ramberg, W. P. Mo, H. Rhodes, D. Tai, V. C. Venezia, and S. G. WuuHigh performance 300 mm backside illumination technology for continuous pixel shrinkageProc. International Electron Devices MeetingWashington, DC, USA2011Dec.8.2.18.2.4
  8. L. Novotny and B. HechtPrinciples of Nano-optics2nd EdCambridge University PressCambridge, UK2012Chapter 12
  9. T. Xu, Y.-K. Wu, X. Luo, and L. J. GuoPlasmonic nano-resonators for high resolution colour filtering and spectral imagingNat. Commun.2010159
  10. Y. Horie, S. H. Han, J. Y. Lee, J. W. Kim, Y. S. Kim, A. Arbabi, C. G. Shin, L. Shi, E. Arbabi, S. M. Kamali, H. S. Lee, S. W. Hwang, and A. FaraonVisible wavelength color filters using dielectric subwavelength gratings for backside-illuminated CMOS image sensor technologiesNano Lett.20171731593164
  11. H. J. Cho and Y. S. DoPlasmonic color filter with robustness against cross talk for compact imaging applicationsCurr. Opt. Photon.202041622
  12. B. Y. Zheng, Y. Wang, P. Nordlander, and N. J. HalasColor-selective and CMOS-compatible photodetection based on aluminum plasmonicsAdv. Mater.20142663186323
  13. H. Satoh and H. InokawaSurface plasmon antenna with gold line and space grating for enhanced visible light detection by a silicon-on-insulator metal-oxide-semiconductor photodiodeIEEE Trans. Nanotechnol.201211346351
  14. H. Satoh, T. Aso, S. Iwata, A. Ono, and H. InokawaRefractive index measurement of aqueous solution using silicon-on-insulator photodiode with surface plasmon antennaProc. Asia-Pacific Workshop on Fundamentals and Applications of Advanced Semiconductor DevicesHakodate, Japan2016Jul.7073
  15. X. Xu, Y. Wang, J. Tang, X. Zhang, and X. LiuRobust automatic focus algorithm for low contrast images using a new contrast measureSensors20111182818294
  16. X. Zhang, Z. Liu, M. Jiang, and M. ChangFast and accurate auto-focusing algorithm based on the combination of depth from focus and improved depth from defocusOpt. Express2014223123731247
  17. P. Śliwiński and P. WachelA simple model for on-sensor phase-detection autofocusing algorithmJ. Comput. Commun.201311117
  18. Lumerical Inc.FDTD 3D electromagnetic simulatorFDTDhttps://www.lumerical.com/products/fdtd/23 September 2020
  19. H. Taguchi and M. EnokidoTechnology of color filter materials for image sensorProc. International Image Sensor WorkshopHokkaido, Japan2011Jun.3437
  20. D. T. F. MarpleRefractive index of ZnSe, ZnTe, and CdTeJ. Appl. Phys.196435539542

Other (20)

S. UchiyamaSuperiority of image plane phase detection AFJ-Stage, Japan, ITE Technical Report2012Sep.2136[Online]. Available: https://www.jstage.jst.go.jp/article/itetr/36.38/0/36.38_17/_article/-char/en

H. Endo"Phase detection pixel built-in image sensor" to realize high speed auto focusJ. Inst. Image Inf. Telev. Eng.201165290292

M. Kobayashi, M. Johnson, Y. Wada, H. Tsuboi, H. Takada, K. Togo, T. Kishi, H. Takahashi, T. Ichikawa, and S. InoueA low noise and high sensitivity image sensor with imaging and phase-difference detection AF in all pixelsITE Trans. Media Technol. Appl.20164123128

A. Morimitsu, I. Hirota, S. Yokogawa, I. Ohdaira, M. Matsumura, H. Takahashi, T. Yamazaki, H. Oyaizu, Y. Incesu, M. Atif, and Y. NittaA 4M pixel full-PDAF CMOS image sensor with 1.58 µm 2×1 On-Chip Micro-Split-Lens technologyITE Tech. Rep.20153958

S. Choi, K. Lee, J. Yun, S. Choi, S. Lee, J. Park, E. Shim, J. Pyo, B. Kim, M. Jung, Y. Lee, K. Son, S. Jung, T. Wang, Y. Choi, D. Min, J. Im, C. Moon, D. Lee, and D. ChangAn all pixel PDAF CMOS image sensor with 0.64 µm × 1.28 µm photodiode separated by self-aligned in-pixel deep trench isolation for high AF performanceProc. Symposium on VLSI TechnologyKyoto, Japan2017Jun.T104T105

T. Okawa, S. Ooki, H. Yamajo, M. Kawada, M. Tachi, K. Goi, T. Yamasaki, H. Iwashita, M. Nakamizo, T. Ogasahara, Y. Kitano, and K. TataniA 1/2 inch 48M all PDAF CMOS image sensor using 0.8 µm Quad Bayer Coding 2 × 2OCL with 1.0 lux minimum AF illuminance levelProc. IEEE International Electron Devices Meeting (IEDM)San Francisco, CA, USA2019Dec.16.3.116.3.4

D. N. Yaung, B. C. Hsieh, C. C. Wang, J. C. Liu, T. J. Wang, W. D. Wang, C. C. Chuang, C. Chao, Y. L. Tu, C. S. Tsai, T. L. Hsu, F. Ramberg, W. P. Mo, H. Rhodes, D. Tai, V. C. Venezia, and S. G. WuuHigh performance 300 mm backside illumination technology for continuous pixel shrinkageProc. International Electron Devices MeetingWashington, DC, USA2011Dec.8.2.18.2.4

L. Novotny and B. HechtPrinciples of Nano-optics2nd EdCambridge University PressCambridge, UK2012Chapter 12

T. Xu, Y.-K. Wu, X. Luo, and L. J. GuoPlasmonic nano-resonators for high resolution colour filtering and spectral imagingNat. Commun.2010159

Y. Horie, S. H. Han, J. Y. Lee, J. W. Kim, Y. S. Kim, A. Arbabi, C. G. Shin, L. Shi, E. Arbabi, S. M. Kamali, H. S. Lee, S. W. Hwang, and A. FaraonVisible wavelength color filters using dielectric subwavelength gratings for backside-illuminated CMOS image sensor technologiesNano Lett.20171731593164

H. J. Cho and Y. S. DoPlasmonic color filter with robustness against cross talk for compact imaging applicationsCurr. Opt. Photon.202041622

B. Y. Zheng, Y. Wang, P. Nordlander, and N. J. HalasColor-selective and CMOS-compatible photodetection based on aluminum plasmonicsAdv. Mater.20142663186323

H. Satoh and H. InokawaSurface plasmon antenna with gold line and space grating for enhanced visible light detection by a silicon-on-insulator metal-oxide-semiconductor photodiodeIEEE Trans. Nanotechnol.201211346351

H. Satoh, T. Aso, S. Iwata, A. Ono, and H. InokawaRefractive index measurement of aqueous solution using silicon-on-insulator photodiode with surface plasmon antennaProc. Asia-Pacific Workshop on Fundamentals and Applications of Advanced Semiconductor DevicesHakodate, Japan2016Jul.7073

X. Xu, Y. Wang, J. Tang, X. Zhang, and X. LiuRobust automatic focus algorithm for low contrast images using a new contrast measureSensors20111182818294

X. Zhang, Z. Liu, M. Jiang, and M. ChangFast and accurate auto-focusing algorithm based on the combination of depth from focus and improved depth from defocusOpt. Express2014223123731247

P. Śliwiński and P. WachelA simple model for on-sensor phase-detection autofocusing algorithmJ. Comput. Commun.201311117

Lumerical Inc.FDTD 3D electromagnetic simulatorFDTDhttps://www.lumerical.com/products/fdtd/23 September 2020

H. Taguchi and M. EnokidoTechnology of color filter materials for image sensorProc. International Image Sensor WorkshopHokkaido, Japan2011Jun.3437

D. T. F. MarpleRefractive index of ZnSe, ZnTe, and CdTeJ. Appl. Phys.196435539542

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