This paper focuses on the structural aspects of two basic types of RF power MOSFETS: the DMOS and the LDMOS. The comparison of the DMOS and LDMOS structures reveals the basic fundamentals of the RF MOSFET device technology and the challenges that exist to improve their RF performance and reliability.
This document focuses on the structural aspects of two basic types of RF power MOSFETs: DMOS (double-diffused) and LDMOS (laterally diffused). It compares their physical structures, highlighting that while VLSI devices use similar principles, RF applications require larger channel lengths, greater junction depths, and thicker gate oxides to handle high power. The text notes that most high-power RF applications utilize DC supply voltages ranging from 20 to 50 volts.
Most high power RF applications use DC supply voltages ranging from 20 to 50 volts.
The LDMOS eliminates parasitic wire bonds by using a diffused p-type region that acts like an ohmic connection.
Insulating material, specifically BeO, can be used to isolate the drain.