Nanoscale investigation of AlGaN/GaN-on-Si high electron mobility transistors

AlGaN/GaN HEMTs are devices which are strongly influenced by surface properties such as donor states, roughness or any kind of inhomogeneity. The electron gas is only a few nanometers away from the surface and the transistor forward and reverse currents are considerably affected by any variation of...

Descripción completa

Detalles Bibliográficos
Autores: Fontserè, Abel, Pérez-Tomás, Amador, Placidi, Marcel, Llobet, Jordi, Baron, N, Chenot, S, Cordier, Y, Moreno, J C, Jennings, M R, Gammon, P M, Fisher, C A, Iglesias, V, Porti, M, Bayerl, A, Lanza, M, Nafría, M
Tipo de recurso: artículo
Fecha de publicación:2012
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/414708
Acceso en línea:http://hdl.handle.net/10261/414708
https://api.elsevier.com/content/abstract/scopus_id/84866342520
Access Level:acceso abierto
Palabra clave:Nanoscale
Electron transistor
http://metadata.un.org/sdg/9
Build resilient infrastructure, promote inclusive and sustainable industrialization and foster innovation
Descripción
Sumario:AlGaN/GaN HEMTs are devices which are strongly influenced by surface properties such as donor states, roughness or any kind of inhomogeneity. The electron gas is only a few nanometers away from the surface and the transistor forward and reverse currents are considerably affected by any variation of surface property within the atomic scale. Consequently, we have used the technique known as conductive AFM (CAFM) to perform electrical characterization at the nanoscale. The AlGaN/GaN HEMT ohmic (drain and source) and Schottky (gate) contacts were investigated by the CAFM technique. The estimated area of these highly conductive pillars (each of them of approximately 20-50 nm radius) represents around 5% of the total contact area. Analogously, the reverse leakage of the gate Schottky contact at the nanoscale seems to correlate somehow with the topography of the narrow AlGaN barrier regions producing larger currents.