Title :
Influence of SiNx passivation on the surface potential of GaInAs and AlInAs in HEMT layer structures
Author :
Arps, M. ; Each, H.-G. ; Passenberg, W. ; Umbach, A. ; Schlaak, W.
Author_Institution :
Heinrich-Hertz-Inst. fur Nachrichtentech. Berlin GmbH, Germany
Abstract :
The surface Fermi level of Ga0.47In0.53As and Al0.48In0.52As is determined by Hall measurements on InP-based HEMT-type van der Pauw structures without and with downstream PECVD SiNx surface passivation. The passivation increases the surface Fermi level towards the conduction band-edge for both semiconductors in particular for low deposition temperatures. While the increase is clearly noticeable on GaInAs it appears less marked on AlInAs. From the finding that the resulting enhancement of carrier density in the GaInAs cap layer does not lower the DC channel resistivity of SiNx passivated HEMT devices conclusions can be drawn about the path of the current in the source and drain regions
Keywords :
Fermi level; Hall effect; III-V semiconductors; aluminium compounds; carrier density; conduction bands; gallium arsenide; high electron mobility transistors; indium compounds; interface states; passivation; silicon compounds; surface potential; Al0.48In0.52As; AlInAs; DC channel resistivity; Ga0.47In0.53As; GaInAs; GaInAs cap layer; HEMT layer structures; Hall measurements; InP; InP-based HEMT-type van der Pauw structures; PECVD SiNx surface passivation; SiN; SiNx passivation; carrier density; conduction band-edge; drain region; low deposition temperatures; passivation; semiconductors; source; surface Fermi level; surface potential; Charge carrier density; Conductivity; HEMTs; Ohmic contacts; Passivation; Plasma temperature; Silicon compounds; Substrates; Superlattices; Surface resistance;
Conference_Titel :
Indium Phosphide and Related Materials, 1996. IPRM '96., Eighth International Conference on
Conference_Location :
Schwabisch-Gmund
Print_ISBN :
0-7803-3283-0
DOI :
10.1109/ICIPRM.1996.492040
