Vertical-channel E-MOSFET usage: A vertical-channel (power) E-MOSFET structure is primarily selected for which application requirement?

Introduction / Context:
Power MOSFETs commonly use a vertical current flow architecture (VMOS, trench MOSFETs). The vertical structure shortens the current path and increases the effective channel area, enabling low on-resistance and large current handling. Recognizing why we choose a vertical channel informs device selection for converters, motor drivers, and power supplies.

Given Data / Assumptions:

• Power-class E-MOSFETs designed for switching.
• Thermal constraints managed via packages and heatsinks.
• Basic trade-offs among voltage rating, current capability, and switching speed.

Concept / Approach:

A vertical conduction path lets many unit cells be paralleled on the die, reducing RDS(on) and spreading current. While such devices can also be designed for high voltage, the core reason for the vertical approach is to deliver high current with low conduction loss. High-frequency capability is more limited by charge storage and capacitances than by channel orientation alone.

Step-by-Step Solution:

Verification / Alternative check:

Datasheets show trench/vertical devices with milliohm-level RDS(on) and high continuous/peak drain currents. Lateral MOSFETs of similar area have much higher RDS(on), limiting current.

Why Other Options Are Wrong:

• High frequencies: determined by gate charge/capacitance and driver strength, not simply vertical orientation.
• High resistances: opposite of the design goal (we want low on-resistance).
• High voltages: achievable, but the key advantage asked is high current capability.

Common Pitfalls:

• Equating high-voltage rating with high-current capability; both depend on die design and cell density.
• Ignoring thermal limits; high current requires adequate heat removal.

Final Answer:

for high currents