Title :
Low resistance ohmic contacts to two-dimensional electron-gas structures by selective MOVPE
Author :
Solomon, P.M. ; Palevski, A. ; Kuech, T.F. ; Tischler, M.A.
Author_Institution :
IBM Thomas J. Watson Res. Center, Yorktown Heights, NY, USA
Abstract :
Selective metalorganic vapor-phase epitaxy (MOVPE) has been used to make very-low-resistance edge contacts to thin n/sup +/ GaAs layers and to two-dimensional electron gas (2DEG) structures. Contact resistance for contacts to the n/sup +/ layer are <1*10/sup -8/ Omega -cm/sup 2/, close to its fundamental limit. Computer simulations of the 2DEG structure reveal the influence of traps at the regrown GaAs-AlGaAs interface which deplete the corner region of carriers. This corner region is influenced by the slope of the sidewall. Low-resistance contacts to the 2DEG structures were achieved both through the use of a postgrowth anneal and through the use of vertical sidewalls.<>
Keywords :
III-V semiconductors; aluminium compounds; contact resistance; electron gas; gallium arsenide; high electron mobility transistors; metallisation; ohmic contacts; semiconductor superlattices; semiconductor-metal boundaries; vapour phase epitaxial growth; 2DEG structure; AuGeNi; GaAs layers; GaAs-AlGaAs; computer simulation; contact resistance; corner region; fundamental limit; ohmic contacts; postgrowth anneal; selective MOVPE; sidewall; traps; two-dimensional electron-gas structures; vertical sidewalls; very-low-resistance edge contacts; Contact resistance; Electron traps; Epitaxial growth; Epitaxial layers; FETs; Gallium arsenide; HEMTs; MODFETs; MOSFETs; Ohmic contacts;
Conference_Titel :
Electron Devices Meeting, 1989. IEDM '89. Technical Digest., International
Conference_Location :
Washington, DC, USA
Print_ISBN :
0-7803-0817-4
DOI :
10.1109/IEDM.1989.74308
