Failure Analyses of Modern Power Semiconductor Switching Devices

Power semiconductor switches such as Power Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) and Insulated Gate Bipolar Transistors (IGBTs) continue to be a leading cause of failure in power electronics systems. With the continued expansion of the power electronics market, reliable switching devices are of utmost importance in maintaining reliable operation of high power electronic systems. An overview of the failure mechanisms of power semiconductor switches identified by two failure analyses at CALCE is presented. The specific applications of power semiconducting switches have a wide range and include semiconductors found in converters for AC/DC power supplies and home appliance motor control board. All observed failures were from devices which experienced a short circuit between the collector and emitter terminals. The causes of the failures are hypothesized to be a combination of manufacturing defects and poor thermal management.