
31GaN High-Voltage Power Devices
1.6 STATE-OF-THE-ART GaN POWER DEVICES
1.6.1 gAn ePitAxy on si And sic suBstrAtes
The epitaxial structure of GaN power switching transistors has to take care of the
requirements toward high voltage capability and switching performance. Principally,
this results in an epitaxial structure according to Figure 1.7, comprising a suitable
back-barrier buffer design that focusses electrons to the channel region even at high
drain bias. Additionally, the design has to guarantee suitable vertical breakdown and
low parasitic dynamic effects.
The envisaged performance of GaN power switching devices will trigger a high
v