Application of lightly doped drain structure to AIGaN/GaN HEMTs by ion implantation technique

摘要

GaN-based wide bandgap semiconductors have superior electrical properties such as a high breakdown field and a high electron saturation velocity, which have been successfully applied to the fabrication of high electron mobility transistors (HEMTs) for high-power applications [1??4]. Further enhancement of the output power is an important issue for this type of AlGaN/GaN device [5], and an increase of the onstate breakdown voltage (V/sub br/) as well as a reduction in on-resistance (R/sub on/) should be very effective for the conventional AlGaN/GaN HEMTs. Here, for the enhancement of the on-state V/sub br/, a lightly doped drain (LDD) structure, which has been widely used for the fabrication of Si metal oxide semiconductor field effect transistors (MOSFETs) [6], may be attractive for the present AlGaN/GaN HEMTs. Recently, an approach to form the LDD structure in an AlGaN/GaN HEMT was made by using F plasma doping [7]. However, there are no reports on the application of ion implantation to form LDD-like Si technology.