Discrete low-voltage power metal-oxide-semiconductor field effect transistors are used in a wide variety of applications with each application relying on different aspects of device behaviour. The conflicting requirements of these applications along with constraints such as legislation, industrial base, and intellectual property have resulted in a diverse array of technologies available in the market. This study outlines the many considerations that are faced when designing a high-performance silicon power MOSFET technology contrasting the trade-offs involved as factors such as on-state resistance, switching performance, reliability, and robustness in the application are optimised.

Up to now the vast majority of insulated gate bipolar transistors (IGBTs) has been produced on silicon (Si) wafers out of the float-zone (FZ) process. FZ crystals can easily be used for this application, but are only available with a diameter of up to 200 mm. However, the use of wafer substrates with a diameter of 300 mm offers a significant increase in productivity and is therefore the diameter of choice for the high-volume production of CMOS devices. In order to benefit from this advantage also for the manufacturing of IGBTs, material out of the magnetic Czochralski process, which is available in 300 mm, had to be adapted. Key issues include crystal originated particles, dopant segregation along the crystal axis, and the higher concentration of oxygen. In particular, the implementation of the field-stop zone by the implantation of protons will lead to the additional formation of hydrogen-decorated C_IO_I complexes which can act electrically as donors. However, by an appropriate adjustment of the processing parameters the electrical characteristics of IGBTs on FZ substrates can be well reproduced.

A new soft-punch-through (SPT) buffer concept for 600–1200 V insulated-gate bipolar transistors (IGBTs) based on thin wafer technology is proposed. The new SPT structure employs an epitaxial layer for the lightly doped n-type drift region, which is grown on a thick starting material or substrate. The n-type substrate serves as the SPT buffer region. The doping concentration of both drift and buffer regions are comparably low with the buffer region having a higher doping level. The design options of this new concept are discussed based on experimental data and 1200 V IGBTs using the new buffer concept are compared to IGBTs employing previously published buffer technology.

From the power loss reduction and safety operation points of view, the direction of power device developments is simply one-way. However, from the application point of view, the direction is wide-ranging. There are a variety of requirements to be considered, such as switching waveforms, operational environments including not only the temperature range but also the combination of the humidity, the cosmic ray endurance, the package compactness and so on. In this study, several efforts are explained as the latest technologies.