A Novel Multi Gate LDMOSFET on SOI for RF Applications

This research consists of SOI MGLDMOSFET structure for high RF power multi gate laterally diffused MOSFET (MGLDMOSFET) is proposed using trenches in the drift zone. Three identical gates are arranged vertically in a trench in the proposed device. At either end of the device, two drain contacts that are vertically extended and connected to the n<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> Si bottom layer. In the p-base, the MGLDMOSFET structure creates many channels for the parallel transmission of current from drain to source. The drain and source contact of the device need to be separated for optimal conduction, a second trench filled with oxide is added and extended vertically on both ends of the drain contacts in the drift zone. A 55 V MGLDMOSFET with an I<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">D</inf> of 5.3 times higher, 3 times decrease in R<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on-sp</inf>, 5.7 times enhancement of peak g<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</inf>, 3 times improvement in BFOM with an increase of 3.1 times in f<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</inf> and an increase of 4.2 times in f<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">max</inf> versus 55 V Conventional LDMOSFET (CLDMOSFET) at same 5 µm cell pitch.