A novel plasmonic metal-semiconductor-insulator-metal (MSIM) color sensor compatible with CMOS technology

Area of Science:

• Photonics and optoelectronics
• Materials science for sensing applications
• Semiconductor device physics

Background:

• Accurate color detection is crucial for biological and industrial applications, particularly in photonic technology.
• Determining light wave characteristics, such as wavelength, is essential for color sensing.
• Existing methods may lack efficiency or separate detection capabilities for distinct RGB color spectra.

Purpose of the Study:

• To propose and design an efficient structure for separate detection of red, green, and blue (RGB) colors.
• To investigate the performance of a novel color detector based on plasmonic filters and PN diodes.
• To demonstrate the compatibility of the designed detector with CMOS technology.

Main Methods:

• Utilizing a plasmonic filter to sense specific wavelengths corresponding to red, green, and blue light.
• Integrating a PN diode to convert detected photons into measurable electrical current.
• Characterizing the detector's response by measuring current density at various input light intensities.

Main Results:

• The proposed detector achieves distinct current densities for blue (27 µA/cm²), green (35 µA/cm²), and red (48 µA/cm²) colors at an input intensity of 1 mW/cm².
• Low input intensities (3.94 µW/cm² for blue, 2.98 µW/cm² for green, 2.25 µW/cm² for red) are sufficient to achieve a current density of 0.1 µA/cm².
• The detector exhibits simple wavelength adjustability and linear operation across different input intensities.

Conclusions:

• The developed plasmonic filter and PN diode structure offers an efficient method for separate RGB color detection.
• The detector's high sensitivity and CMOS compatibility make it suitable for integration into devices like cameras and displays.
• Further improvements in sensitivity can be achieved by employing high-precision photodetector structures like PIN diodes.