Yazar "Yucekul, Mustafa Ozber" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • [ X ]
    Öğe
    Enhancing near-infrared sensitivity of CMOS image sensors using a hemispherical photon-trapping structure
    (Springer, 2025) Yucekul, Mustafa Ozber; Tanrikulu, Mahmud Yusuf
    CMOS image sensors are extensively utilized in applications ranging from consumer electronics to biomedical imaging and autonomous systems. Despite their high efficiency in the visible spectrum, their sensitivity in the near-infrared (NIR) region remains significantly low due to the limited absorption of silicon beyond 700 nm. To address this challenge, we propose a novel light-trapping strategy incorporating a hemispherical structure at the silicon interface. This design facilitates the direct transmission of normally incident light into the silicon layer while enhancing light scattering and redistribution. Additionally, a pyramidal structure positioned below the silicon layer refracts transmitted light, further improving absorption. To minimize optical crosstalk between adjacent pixels, a deep trench isolation (DTI) structure is implemented. The optical performance of the proposed structure is evaluated through finite-difference time-domain (FDTD) simulations, demonstrating up to a 36% enhancement in optical efficiency at a wavelength of 1100 nm compared to conventional BSI CMOS image sensor designs. These findings highlight the potential of hemispherical photon-trapping strategies for enhancing CMOS image sensor performance in NIR applications such as machine vision and biomedical imaging.
  • [ X ]
    Öğe
    Enhancing near-infrared sensitivity with GaAs-based hybrid CMOS image sensors
    (SPIE-Society of Photo-Optical Instrumentation Engineers, 2025) Yucekul, Mustafa Ozber; Tanrikulu, Mahmud Yusuf
    Complementary metal-oxide-semiconductor (CMOS) image sensors are widely used in applications such as time-of-flight systems, machine vision, mobile devices, and medical imaging due to their versatility and compact structure. However, enhancing their sensitivity in the near-infrared (NIR) region remains a significant challenge, largely due to insufficient light absorption within this spectral range. We propose an innovative solution to this limitation by integrating GaAs semiconductor material with silicon in a hybrid CMOS image sensor. The design incorporates a 2 mu mx2 mu m pixel architecture combined with a deep trench isolation structure, which significantly enhances light absorption and efficiency in the NIR region. This approach achieves more than a twofold increase in NIR sensitivity in the 800- to 1000-nm wavelength range compared with conventional backside-illuminated CMOS image sensors. Simulation results highlight the substantial potential of the GaAs-based hybrid structure in advancing the performance of CMOS image sensors for applications requiring improved sensitivity in the NIR region. To the best of our knowledge, the proposed structure is the first of its kind reported in the literature.