A practical model, adequate for full reproduction of inhomogeneous Schottky diodes' forward characteristics over wide high-temperature and bias ranges, is proposed. According to this p-diode model, the Schottky contact current is considered to flow through m parallel-connected internal diodes, each with stable, constant barrier height and specific series resistance (both main model parameters). The value of m, required to reproduce the entire electrical forward behavior of a non-uniform Schottky contact, is directly connected to a particular model parameter (peff), used to define the inhomogeneity degree. The p-diode model was tested on forward characteristics measured for both Ni and commercial Ti Schottky diodes on 4H-SiC, which exhibited varying degrees of inhomogeneity. Excellent replication of experimental curves was achieved for all investigated samples, even those with obvious irregularities, such as “humps”, explained in the model by the series resistances’ influence. In the case of m=1, the proposed model does not produce identical results with the conventional model of a homogeneous Schottky contact if peff ± 0. The value of this parameter indicates how much of an inhomogeneous contact's area is essentially used for current conduction.

A partially electrically isolated package with a gold wire and fully isolated solution with a metallic piston, respectively, are designed and tested for high temperature sensors (400°C) based on SiC Schottky barrier diodes (SBD). Electrical behavior and sensor performance are very close for both packaging solutions. The stress due to contact pressure and higher cost are some disadvantages for pressure contact technology.

This paper evaluates the non-uniformity degree of platinum and chromium Schottky contacts on silicon carbide. The forward characteristics of experimental samples were acquired in a wide, 60–500 K, temperature range. Microstructural and conventional electrical characterizations were performed, revealing the presence of inhomogeneities on the contact surface. The main parameters were extracted using inhomogeneity models of varying complexity levels. Their relevance is discussed with respect to the models’ applicable, limited, temperature ranges. Finally, complete forward curve fitting was achieved using p-diode modeling, evincing that each type of contact behaves as four parallel-connected ideal diodes. Since these parallel diodes have varying influences on the overall device current with temperature and bias, operable domains can be identified where the samples behave suitably.