Abstract

AlGaN/GaN power HFETs grown on a 200nm thick AlN sub-buffer layer are investigated. The presence of a steady kink in the static and dynamic drain-to-source current characteristics is attributed to floating-body (FB) effects that result from the AlN sub-buffer layer. A method to extract the off-state body-to-source voltage (VBS) is applied and the coherence of the results confirms that FB effects are present in this type of structures. To our knowledge, this is the first time that floating-body effects are reported and modeled in AlGaN/GaN HFETs.