PROPERTIES OF SCHOTTKY CONTACT OF AL ON SIGE ALLOYS

Electrical properties of Schottky contacts of Al on p-Si1-xGex alloys were investigated. The Si1-xGex strained layers were grown on p-Si sub strates by using rapid thermal process/very low pressure-chemical vapo r deposition. Low reverse currents were obtained. It was found that th e Schottky barrier height of Al/p-Si1-xGex contacts decreased with inc reasing Ge fraction. The decrement is in accordance with the decrement of the band gap of the strained Si1-xGex. The Fermi level at the inte rface is pinned at about 0.43 eV below the conduction band. The influe nce of strain relaxation for SiGe alloy layers and the Si sacrificial cap layers on the properties of Schottky contacts were also investigat ed. (C) 1996 American Institute of Physics.