Several mechanisms contribute to leakage currents in nanoscale devices:
Quantum Tunneling: At nanoscale dimensions, electrons can tunnel through thin insulating barriers, leading to leakage. Thermionic Emission: High electric fields can provide enough energy for electrons to overcome potential barriers, resulting in leakage. Defect-Assisted Tunneling: Defects within the material can provide pathways for leakage currents to flow through. Subthreshold Leakage: In MOSFETs, leakage can occur when the device is supposed to be off, primarily due to the weak inversion layer.
