Image sensors using thin-film absorbers.

Area of Science:

• Materials Science
• Electrical Engineering
• Photonics

Background:

• Complementary metal-oxide semiconductor (CMOS) image sensors dominate consumer electronics due to wafer-scale manufacturing and silicon photodiodes' suitability for human vision replication.
• Thin-film absorbers offer alternative photoactive materials with thicknesses comparable to or smaller than the wavelength of interest, enabling novel functionalities.
• Thin-film image sensors represent an emerging device category with potential for applications beyond silicon's limitations, such as transparency and short-wave infrared detection.

Purpose of the Study:

• To present the development and performance metrics of various thin-film image sensors at imec, utilizing organic, quantum dot, and perovskite photodiode technologies.
• To explore methodologies for selecting optimal sensor architectures, including integration with thin-film transistors or CMOS platforms.
• To demonstrate emerging use cases through proof-of-concept applications of these advanced thin-film image sensors.

Main Methods:

• Fabrication and characterization of thin-film photodetectors based on organic, quantum dot, and perovskite materials.
• Evaluation of key performance indicators (figures of merit) for the developed photodetectors.
• Analysis of integration strategies, comparing thin-film transistor and CMOS architectures for sensor systems.

Main Results:

• Demonstration of several types of thin-film image sensors with characterized figures of merit.
• Comparative analysis of different thin-film materials (organic, quantum dot, perovskite) for photodetection.
• Successful integration of thin-film sensors into proof-of-concept systems showcasing novel applications.

Conclusions:

• Thin-film image sensors offer significant potential for expanding imaging capabilities beyond conventional silicon-based technologies.
• The choice of sensor architecture (TFT or CMOS integration) is critical for optimizing performance based on application requirements.
• Emerging thin-film sensor technologies pave the way for new applications in areas like infrared imaging and transparent electronics.