Low-frequency noise in AlN/AlGaN/GaN metal-insulator-semiconductor devices: A comparison with Schottky devices.Show others and affiliations
2014 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 116, no 5, p. 8article id 054510Article in journal (Refereed) Published
Abstract [en]
We have systematically investigated low-frequency noise (LFN) in AlN/AlGaN/GaN metalinsulator- semiconductor (MIS) devices, where the AlN gate insulator layer was sputteringdeposited on the AlGaN surface, in comparison with LFN in AlGaN/GaN Schottky devices. By measuring LFN in ungated two-terminal devices and heterojunction field-effect transistors (HFETs), we extracted LFN characteristics in the intrinsic gated region of the HFETs. Although there is a bias regime of the Schottky-HFETs in which LFN is dominated by the gate leakage current, LFN in theMIS-HFETs is always dominated by only the channel current. Analyzing the channel-current-dominated LFN, we obtained Hooge parameters α for the gated region as a function of the sheet electron concentration ns under the gate. In a regime of small ns, both the MIS- and Schottky-HFETs exhibit α ∝ ns–1. On the other hand, in a middle ns regime of the MIS-HFETs, α decreases rapidly like ns–ξ with ξ~2-3, which is not observed for the Schottky- HFETs. In addition, we observe strong increase in α ∝ ns3 in a large ns regime for both the MIS- and Schottky-HFETs. [ABSTRACT FROM AUTHOR]
Place, publisher, year, edition, pages
American Institute of Physics (AIP), 2014. Vol. 116, no 5, p. 8article id 054510
National Category
Condensed Matter Physics
Identifiers
URN: urn:nbn:se:liu:diva-151621DOI: 10.1063/1.4892486OAI: oai:DiVA.org:liu-151621DiVA, id: diva2:1251679
2018-09-272018-09-272019-12-31Bibliographically approved