Title :
Piezoelectric GaN sensor structures
Author :
Zimmermann, T. ; Neuburger, M. ; Benkart, P. ; Hernández-Guillén, F.J. ; Pietzka, C. ; Kunze, M. ; Daumiller, I. ; Dadgar, A. ; Krost, A. ; Kohn, E.
Author_Institution :
Dept. of Electron Devices & Circuits, Univ. of Ulm, Germany
fDate :
5/1/2006 12:00:00 AM
Abstract :
Free-standing GaN and AlGaN/GaN cantilevers have been fabricated on (111) silicon substrate using dry etching. On these cantilevers, a piezoresistor and a high-electron-mobility transistor (HEMT) structure have been realized, and the piezoresponse has been characterized. Cantilever bending experiments resulted in a Young´s modulus of approximately 250 GPa, a sensitivity of K∼90, and a modulation of the HEMT current of up to 50%. It is seen that the piezoresponse could be related to both the bulk properties and the properties of the heterostructure interface.
Keywords :
III-V semiconductors; aluminium compounds; cantilevers; electric sensing devices; etching; gallium compounds; high electron mobility transistors; microsensors; piezoelectric devices; piezoresistive devices; wide band gap semiconductors; (111) silicon substrate; AlGaN-GaN; HEMT; Young modulus; bulk properties; dry etching; heterostructure interface; high electron mobility transistor; microelectromechanical system; piezoelectric sensor; piezoresistor structure; piezoresponse characterization; Aluminum gallium nitride; Compressive stress; Dry etching; Gallium nitride; HEMTs; Optical polarization; Piezoresistance; Silicon; Tensile stress; Thermal stresses; AlGaN/GaN; cantilever; microelectromechanical system (MEMS); piezoresistor; polarization; sensor;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2006.872918
