Ohmic versus rectifying contacts through interfacial dipoles: Al/InxGa1-xAs

The Schottky barrier height at Al/n-InxGa1-xAs contacts (0.19 < x < 0.38) w as engineered by fabricating Si bilayers at the metal-semiconductor interfa ce. Si interlayers grown under As flux led to the suppression of the barrie r, while interlayer deposition under Al flux yielded an increase in the bar rier height. In situ X-ray photoemission spectroscopy results and ex situ c urrent-voltage measurements indicated a barrier tunability range of about 0 .8 eV, with ideal ohmic behavior of diodes engineered for low barrier heigh t, and barrier heights as high as 0.7 eV in diodes engineered for high barr ier height. (C) 1999 Elsevier Science B.V. All rights reserved.