A Simple Drain Current Model for MOS Transistors with the Lorentz Force Effect

Area of Science:

• Solid State Physics
• Semiconductor Device Physics
• Magnetic Sensors

Background:

• Metal-Oxide-Semiconductor (MOS) transistors are fundamental semiconductor devices.
• The Lorentz force, a physical phenomenon, arises from the interaction of charged particles with magnetic fields.
• Existing models for MOS transistor drain current do not typically account for Lorentz force effects.

Purpose of the Study:

• To propose a novel concept for modeling drain current in rectangular normal MOS transistors incorporating the Lorentz force.
• To characterize the MOS transistor as a magnetic sensor.
• To develop new drain current equations for the strong inversion region under Lorentz force influence.

Main Methods:

• Application of a DC loop current through an on-chip metal loop to generate a magnetic field.
• Measurement of drain current changes in the MOS transistor due to the induced Lorentz force.
• Development and validation of new drain current equations based on observed mobility changes.

Main Results:

• The drain current in MOS transistors decreases when subjected to Lorentz force from both directions.
• A change in carrier mobility of approximately 4.45% was observed in the strong inversion region.
• The proposed drain current model achieved an average error of less than 2% compared to experimental measurements.

Conclusions:

• The Lorentz force significantly affects the drain current in MOS transistors, particularly in the strong inversion region.
• The developed model provides an accurate method for predicting drain current behavior under magnetic fields.
• This research establishes the MOS transistor's potential as a sensitive magnetic sensor.