Filter-Less Polychromatic Recognition in One Photosensitive Oscillator via Dual-Perception Feature Decoupling

Area of Science:

• Optoelectronics and Materials Science
• Advanced Semiconductor Devices
• Spectroscopic Instrumentation

Background:

• Filter-less polychromatic photodetectors are crucial for miniaturized optoelectronic systems but typically require multiple semiconductors.
• Achieving polychromatic perception with a single semiconductor without optical components is a significant challenge.
• Existing technologies face limitations in spectral recognition, color imaging, and biometrics due to integration complexity.

Purpose of the Study:

• To demonstrate a novel filter-less photosensitive ring oscillator (PSRO) for polychromatic recognition using a single amorphous semiconductor.
• To decouple oscillation frequency and relaxation characteristics for distinguishing both wavelength and intensity.
• To present a new methodology for polychromatic perception and advanced spectrometers.

Main Methods:

• Fabrication of a PSRO based on amorphous indium gallium zinc oxide (a-IGZO).
• Utilizing the intrinsic localized defective states of a-IGZO for relaxation character.
• Employing a fifth-order oscillation architecture to construct frequency features for polychromatic detection.
• Integrating the PSRO with a response processing circuit for system demonstration.

Main Results:

• The developed PSRO exhibits a response oscillation frequency up to approximately 160 Hz.
• Recognizable detection of primary colors (450 nm, 532 nm, and 635 nm) was achieved.
• The device demonstrated reliable performance across an intensity range of 50 to 1500 µW cm⁻².
• Successful demonstration of an integrated system for polychromatic recognition.

Conclusions:

• A filter-less PSRO based on a single amorphous semiconductor offers a viable solution for polychromatic recognition.
• The decoupling of oscillation frequency and relaxation character enables simultaneous wavelength and intensity detection.
• This approach provides a new methodology for developing advanced spectrometers and polychromatic perception systems.
• The demonstrated integration system highlights the practical application feasibility of the PSRO technology.