This work reports on the morphological and electrical characteristics of Ni/4H-SiC Schottky contacts, fabricated on epitaxial layers intentionally covered by micrometric size Gedroplets. Specifically, the Ge-droplets behave as preferential paths for the vertical current conduction, as observed at nanometric scale by conductive atomic force microscopy. As a consequence, the electrical I-V characteristics of these Ni contacts revealed the presence of a double-barrier, thus indicating an inhomogeneity in the interface. This behavior was associated to the local Schottky barrier lowering contribution due to the Ge-presence. These results can be useful to explore the possibility of controlling the contact (Schottky or Ohmic) properties by changing the size and the distribution of the surface impurities.
Preliminary study on the effect of micrometric Ge-droplets on the characteristics of Ni/4H-SiC Schottky contacts
Vivona M;Giannazzo F;Roccaforte F
2015
Abstract
This work reports on the morphological and electrical characteristics of Ni/4H-SiC Schottky contacts, fabricated on epitaxial layers intentionally covered by micrometric size Gedroplets. Specifically, the Ge-droplets behave as preferential paths for the vertical current conduction, as observed at nanometric scale by conductive atomic force microscopy. As a consequence, the electrical I-V characteristics of these Ni contacts revealed the presence of a double-barrier, thus indicating an inhomogeneity in the interface. This behavior was associated to the local Schottky barrier lowering contribution due to the Ge-presence. These results can be useful to explore the possibility of controlling the contact (Schottky or Ohmic) properties by changing the size and the distribution of the surface impurities.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.