Semi-conductive components - Monolithic power integration

In power electronics, functions are mainly related to the control and conversion of electrical energy. For example, power semiconductors are mainly used as switches in energy converters (rectifiers, choppers, inverters, etc.). However, power semiconductors are also used for specific protection functions in electrical equipment. The first power components (diodes, bipolar transistors, thyristors) capable of controlling high voltages and currents were marketed in the 1950s, and since then, semiconductor components have gradually replaced electromechanical solutions for power converters. In the 1970s, MOS (Metal/Oxide/Semiconductor) structures, characterized by high input impedance, made it possible to do away with the current controls of purely bipolar power devices. The first MOS power transistors were born, foreshadowing the numerous power components based on the combination of MOS and bipolar technologies. In the 1980s, a technological step forward was taken with the IGBT (Insulated Gate Bipolar Transistor), which became the most widely used power component for medium-power applications. Over the last twenty years or so, power electronics integration has expanded, driven by specific markets such as automotive, lighting and household appliances. Depending on power levels and constraints, integration solutions can be monolithic or hybrid. In this dossier, we will look at monolithic integration and its two main families: Smart Power integration and functional integration. Hybrid integration is covered in the following issue [D 3 111] .

Although the performance requirements for power components are different from those for integrated circuits, the development of power components over the last twenty years is closely linked to advances in microelectronic technologies in the field of integrated circuits. Indeed, the boom in integrated circuits for signal and information processing has been accompanied by a major research effort that has led to the development of new technological processes and reduced dimensions.

The synergy between the fields of power and signal processing was triggered by the introduction of MOS technologies in power devices. The on-state resistance performance of vertical power MOS structures (VDMOS) has been significantly improved by the reduction in size that has enabled an increase in the number of cells per unit area. The IGBT, currently one of the most widely used devices in power electronics, is a direct spin-off from this work. Smart Power" devices combining MOS-controlled power devices and signal processing circuits are a perfect illustration of this trend.

These new integrated power functions can be implemented in one of two ways: either...