Comparative study of chemical and polarization characteristics of Pd/Si and Pd/SiOx/Si Schottky-barrier-type devices

Abstract

The chemical nature of semitransparent (∼125 Å) palladium on silicon Schottky-barrier-type devices was determined by complementary AES and ISS techniques. Postdeposition analyses of metal-semiconductor (MS) and metal–thin-insulator–semiconductor (MIS) devices prepared without heat treatment showed that palladium silicide is formed in the MS structures, while the presence of an ultrathin (∼30 Å) purposefully grown semiconductor oxide film inhibits the chemical reaction between Pd and Si in the metal overlayer. Chemical bonding information extracted from the AES data was correlated with barrier-height measurements obtained from capacitance-vs-voltage (C-V) and current-vs-voltage (I-V) electrical characteristics of these devices.

Investigation of hydrogen sensing properties and aging effects of Schottky like Pd/porous Si

“…It is well known that a silicon oxide layer between silicon and palladium prevent migration of Si into Pd or vice versa. Otherwise formation of palladium silicide in the metal-semiconductor structures can occur without heat treatment [16]. As is shown in our previous work, deposi- tion of palladium on porous silicon in the electroless process takes place simultaneously with silicon oxidation [2].…”

Electrostatically defined quantum dots in a Si/SiGe heterostructure

“…Electric top-gates are fabricated by electron beam lithography and palladium (Pd) evaporation 29 . The Pd on the device surface pins the Fermi energy at about 750 meV 30,31 below the conduction band edge. This strong pinning is as consequence of surface states at the Pd-Si interface.…”

Lateral quantum dots in Si∕SiGe realized by a Schottky split-gate technique

“…Pd yields a Schottky barrier height of 0.74 eV on n-type silicon, 13 which is among the highest available in this material system. Subsequently, the split-gate structures were written by e-beam lithography into Polymethl methacrylate ͑PMMA͒ resist in a LEO Supra 35 scanning electron microscope with a Raith Elphyϩcontrol unit.…”