1T Pixel Using Floating-Body MOSFET for CMOS Image Sensors

Area of Science:

• Solid-state physics
• Semiconductor device physics
• Image sensor technology

Background:

• CMOS image sensors (CIS) are ubiquitous in modern imaging.
• Traditional CIS pixels often require multiple transistors, increasing complexity and power consumption.
• There is a continuous need for more efficient and compact pixel designs.

Purpose of the Study:

• To introduce and characterize a novel single-transistor (1T) pixel for CMOS image sensors.
• To develop an analytical model for the conversion gain of the 1T pixel.
• To investigate the impact of different design configurations and fabrication parameters on pixel performance.

Main Methods:

• Fabrication of 1T pixels using a floating-body MOSFET structure.
• Development of analytical models to describe conversion gain.
• Experimental validation by comparing theoretical predictions with measured data.
• Implementation and testing of various pixel configurations (e.g., rectangular-gate, ring-gate).

Main Results:

• The 1T pixel functions as both a photo-sensing device and a source-follower transistor.
• Analytical models for conversion gain were derived and validated against experimental results.
• Different pixel configurations and fabrication variations were explored, demonstrating tunable characteristics.
• The 1T pixel structure shows potential for charge storage and evacuation control.

Conclusions:

• The presented 1T pixel offers a simplified and potentially more efficient alternative for CIS.
• The developed models provide a theoretical basis for understanding and optimizing 1T pixel performance.
• Further research into optimized designs and fabrication processes can enhance the utility of this 1T pixel technology.