4. MOSFETs - Basic Operation and Characteristics
The chapter on MOSFETs introduces the basic operation and characteristics of Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) emphasizing their high input impedance and scalability for VLSI circuits. Key structural components, operational modes, I-V characteristics, and fundamental parameters are discussed extensively. The chapter concludes with the laboratory characterization methods and the impact of technology scaling based on Moore's Law.
Sections
Navigate through the learning materials and practice exercises.
What we have learnt
- MOSFETs are voltage-controlled 3-terminal devices characterized by high input impedance and majority carrier operation.
- The fundamental operating regions of MOSFETs include cutoff, triode, and saturation, with specific current flow conditions.
- Key parameters such as transconductance and output resistance are crucial for evaluating MOSFET performance, with design implications in advanced technology nodes.
Key Concepts
- -- MOSFET (MetalOxideSemiconductor FieldEffect Transistor)
- A voltage-controlled three-terminal device used in modern electronics characterized by its high input impedance.
- -- Threshold Voltage (V_th)
- The minimum gate-to-source voltage that is required to create a conducting path between the drain and source terminals.
- -- Transconductance (g_m)
- A measure of the sensitivity of the drain current to changes in the gate-source voltage, often used to evaluate the gain of the device.
- -- ShortChannel Effects
- Phenomena that occur in MOSFETs with small channel lengths, impacting performance metrics such as velocity saturation and drain-induced barrier lowering.
- -- IV Characteristics
- The relationship between the drain current and the drain-source voltage under various gate-source voltage conditions, important for understanding device behavior.
Additional Learning Materials
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