HCI SOA Enhancement for EDNMOS with Metal Field Plate

This paper discusses Hot-Carrier Injection (HCI) for extended-drain nMOSFET (EDNMOS) with Metal Field Plate (MFP). The HCI linear-region drain current degradation is compared between a typical EDNMOS with MFP, and a typical EDNMOS without MFP. The difference in HCI linear-region drain current degradation is described using Technology Computer-Aided Design (TCAD) simulations that show the magnitude of the electric field and impact ionization at the drain to gate edge region. Additionally, the HCI Safe-Operating Area (SOA) is simulated from the Aging HCI silicon data using an AgeMOS model. It is shown from the HCI SOA that there are improvements in the HCI reliability operating boundary for the EDNMOS with MFP as compared to the EDNMOS without MFP, especially in the switch (i.e. high V
d
and low V
g
) region.