Singular Point Source MOS (S-MOS) Cell Concept

Abstract

A Singular Point Source MOS (S-MOS) cell concept suitable for power semiconductor MOS based devices is presented. The S-MOS differs from a standard Planar or Trench MOS cell in the manner by which the total channel width per device area is determined. The S-MOS cell channel width is defined as the peripheral length of a line running approximately along the N++ source and P channel junction which is situated on a single gated trench side-wall. The length of the line can be established from a singular point source implant for forming the N++ source region which corresponds to the shape of the N++/P junction. The total channel width will therefore depend on the total number of gated trench sidewalls per chip. Despite a relatively short channel width obtained on a single trench side-wall, narrow mesa dimensions between adjacent trenches will provide an adequate number of cells for adjusting the total channel width as required for a given device performance. The S-MOS can be realized by simple manufacturing processes and presents an alternative approach for MOS cell layouts by decoupling critical design parameters (e.g., channel width, trench dimension and NPN transistor area). This flexibility can lead to lower overall losses, lower gate charge levels, improved switching robustness and controllability for different MOS based devices.

Enhancing Efficiency and Reliability of Electric Vehicles via Adaptive E-Gear Control

“…The current at which the gear switching happens has been determined offline according to the semiconductor properties and results from simulations, where it was evaluated that the highest efficiency could be achieved by switching at the semiconductor's peak efficiency current. This approach differs from what is described in [7].…”

“…In this paper, we consider an automotive converter equipped with an Adjustable Switch Hybrid Concept (AHS) based electric gear technology, presented in [7], and propose an automatic gear control strategy to increment the range and lifetime of BEVs by reducing converter losses and damages.…”

“…Recently, a new converter switching concept has been introduced in [7], [14]: the AHS is an extension of the Cross Switch (XS) Hybrid concept, originally comprising a fixed parallel arrangement of Silicon Insulated-Gate Bipolar Transistors (IGBTs) and unipolar SiC Metal-Oxide-Semiconductor Field-Effect Transistors (MOS-FETs), hence relying on the different electrical characteristics of both devices. In the AHS, the Si-IGBT to the SiC-MOSFET ratio is dynamically adjusted through the gate units depending on the load conditions, resulting in a variable configuration of the converter.…”