The design basis of general components for high-power MOSFET CAD

Abstract

The structure and design basis of CAD for high- power MOSFET are presented. Keyworh - MOSFET, CAD. Recently the mass-production of high-power metal-oxide- semiconductor field-effect transistors (MOSFET) grows up. It is caused by their better operational parameters in comparison with bipolar transistors. The main fields of high-power MOSFET applications are computer engineering, sources of secondary power supply in electronics etc. The MOSFETs with variable operating voltages, currents and speed are required. However the design of MOSFET is connected with some problems which arise from features of this devices (l). MOSFET is characterized by high voltages, low resistance in open state, high currents, commutation voltage and speed and it defmes main problems at design. MOSFET electrical parameters come into collision on means for obtaining of parameters and it forces to search for compromises at design stage. For example, for obtaining of low resistance at the open state it is necessary to reduce resistivity and increase the crystal area at it causes breakdown voltage reduction, switching time increase and considerable yield ratio decrease. Above-mentioned aspects prevent to use optimal design and technological decisions and lead to high production costs. Presented CAD is oriented to design of self-aligned DMOSFETs with polysilicon gate, dual-leveled electrode arrangement and multicellular structure, because such construction allows to easy realize high breakdown voltage and low resistance at open state. The main aim of proposed CAD is provision of design high speed and quality improvement at research and design works.