Gallium nitride based, integrated, bilateral switch power device with substrate-biasing diodes

An integrated bilateral switch power device based on gallium nitride, comprising a die including:

• a semiconductor body including a substrate and stack of semiconductor layers on the substrate;
• a substrate node electrically coupled to a backside of the substrate;
• a first switch field effect transistor integrated in the substrate and including a first gate terminal and a first conduction contact region coupled to a top of the stack of semiconductor layers;
• a second switch field effect transistor integrated in the substrate and including a second gate terminal and a second conduction contact region coupled to the top of the stack of semiconductor layers;
• a substrate-biasing network configured to electrically couple the substrate node selectively to the first conduction contact region if the first conduction contact region is at a lower potential than the second conduction contact region or to the second conduction contact region if the second conduction contact region is at a lower potential than the first conduction contact region, the substrate biasing network including a first diode-connected transistor and a second-diode connected transistor each coupled to the substrate node.

A method, comprising:

• applying a first gate voltage to a first gate of a first switch field effect transistor integrated in a semiconductor body including a semiconductor substrate and a plurality of semiconductor layers on the semiconductor substrate, a conductive substrate node coupled to a bottom of the semiconductor substrate;
• applying a second gate voltage to a second gate of a second switch field effect transistor integrated in a semiconductor body including a semiconductor substrate and a plurality of semiconductor layers on the semiconductor substrate, the first and second switch field effect transistors coupled together as a bilateral switch;
• applying a voltage between a first conduction contact region of the first switch field effect transistor coupled to a top of the stack of semiconductor layers and a second conduction contact region of the second switch field effect transistor coupled to the top of the stack of semiconductor layers;
• selectively coupling, with a substrate-biasing network, the substrate node to the first conduction contact region if the first conduction contact region is at a lower potential than the second conduction contact region or to the second conduction contact region if the second conduction contact region is at a lower potential than the first conduction contact region, the substrate biasing network including a first diode-connected transistor and a second-diode connected transistor each coupled to the substrate node.