Investigation of contact resistivity for Au—Ti—Pd—n-Si ohmic contacts for impatt diodes

Abstract

Both contact resistivity of Au—Ti—Pd—n-Si ohmic contact and mechanism of current flow are studied in the 100—360 K temperature range. A method is proposed for reduction of error in determination of contact resistivity based on analysis of statistical dependences of the measured contact resistivity values (which are in the range of (0.9—2)•10–5 Ω•cm2). On the basis of the contact resistivity temperature dependence, it is found for an ohmic contact with barrier height of 0.22 eV that the field mechanism of current flow is predominant in the 100—200 K temperature range, while thermal-field emission with activation energy of 0.08 eV is predominant in the 200—360 K temperature range.

Method for data processing in application to ohmic contacts

“…On the other hand, the correlation between ρ c and R s can be of physical nature, that is, changes in both parameters may be related to the variations in the concentration of the doping admixture in the film, which will lead to a positive correlation between the parameters. It is known that with a negative correlation, the replacement of R s , determined from a specific template as the average value on the plate, can reduce the error in determination of ρ c [7].…”