I. Avramova

Thin-film coating of Cu-Co oxide catalyst on lanthana/zirconia films electrodeposited on stainless steel

Abstract In this paper we report for the first time that lanthana/zirconia films, electrodeposited on a stainless steel substrate, are suitable for supporting a thin-film coating of Cu-Co oxide catalyst. The catalyst is active towards the O 2 +CO and NO+CO reactions.

High Temperature and High Power Stability Investigation of Al-Based Ohmic Contacts to p-Type 4H-SiC

Three types of low resistivity Al-based ohmic contacts to p-type 4H-SiC, Au/Al/Si, Au/AlSiTi and Au/Ti/Al have been studied. Reproducible contact resistivity of 8.30x10 -5 Ωcm 2 , 6.42x10 -5 Ωcm 2 and 1.42x10 -5 Ωcm 2 has been obtained for Al/Si, AlSiTi and Al/Ti contacts, respectively. The investigation of the thermal properties of Al-based contacts shows that addition of Ti to the contact composition improves its stability at ageing temperatures as high as 700 o C, at operating temperatures up to 450 o C and current densities of 10 3 A/cm 2 . XPS analysis of as-deposited and annealed contacts has been performed to explain the observed thermal properties.

Nanolayered Au/Ti/Al Ohmic Contacts to P-Type SiC: Electrical, Morphological and Chemical Properties Depending on the Contact Composition

Electrical, morphological and chemical properties of nanolayered Au/Ti/Al ohmic contacts with different Ti:Al ratio are investigated. Contact resistivities of 1.42×10-5 ⋅cm2 and 1.21×10-5 ⋅cm2 are achieved for Au/Ti(70)/Al(30) and Au/Ti(30)/Al(70) contacts, respectively. It is found that the Ti:Al ratio does not affect the lowest resistivity value but influences on the optimal annealing temperature at which it is obtained. The different optimal annealing temperature provokes different element distributions and interface chemistry of the annealed contacts. An increase of the Al concentration in the contact composition causes essentially the surface morphology leading to an increase in surface roughness of the as-deposited and annealed contacts.