Canola oil was structured into oleogels with different amounts of carnauba wax, and their processing performances were assessed as an alternative to solid fat for imitation cheese low in saturated fat. The contents of solid fat in the oleogels were less vulnerable to the change in temperature than the palm oil. The replacement of palm oil with oleogels produced cheese samples with harder and more cohesive/chewy textures. Dynamic and transient viscoelastic measurements demonstrated that the use of oleogels was effective in increasing the elastic nature of the cheeses. Two distinct components with different proton mobilities were observed in the imitation cheeses, and longer T2 relaxation times were detected in the oleogel samples. The meltability of the cheese with palm oil was not significantly different from those with 3% and 6% oleogels. The saturated fat level of the oleogel cheese was significantly reduced from 45.70 to 5.20%. The application of canola oil-carnauba wax oleogels could successfully produce imitation cheese high in unsaturated fat and low in saturated fat. This study thus demonstrated that the health-functional properties of imitation cheese could be enhanced by using oleogels.

The microstructural and electrical properties of Er-germanides formed by a solid state reaction between Er and Ge have been investigated at different germanide formation temperatures from 400 to 700 C. Er 26 Ge 23 and Er 3 Ge 4 phases were formed at a germanidation temperature of 400 C, followed by the formation of Er 3 Ge 4 and Er 2 Ge 3 at 500 to 600 C and then ErGe 2.16 at 700 C. The sheet resistance gradually decreased with increasing annealing temperature up to 600 C, which could be associated with the phase transformation from Er-rich to Ge-rich Er-germanides. Er-germanides on n-type Ge showed Schottky behavior at low formation temperatures of less than 600 C. Above 600 C they exhibit Ohmic behavior. However, due to strong Fermi level pinning, Er-germanide contact to p-type Ge substrates was demonstrated to be Ohmic regardless of the annealing temperatures. The conversion of Schottky to Ohmic behavior could be attributed to a significant increase in current in the forward and reverse biases caused by the formation of square-shaped microvoids driven by Ge out-diffusion near the interface between germanides and the Ge substrate.

We have investigated electrical and microstructural properties of Pt-germanides as a function of rapid thermal annealing (RTA) temperature. As increasing RTA temperatures, Pt films reacted with Ge and produced Pt-germanides. The Pt 2 Ge 3 phase was completely transformed into PtGe 2 at the RTA temperatures in the excess of 500 C. The specific contact resistivity (q c ) and sheet resistance (R s ) were investigated as a function of germanidation temperatures. Both q c and R s increased after the RTA process of 400 C, and then decreased with increasing annealing temperature. The increase in R s and q c at 400 C could be associated with the presence of a highly resistive Pt 2 Ge 3 phase. RTA process at 700 C led to the severe degradation of surface and interface morphologies of a PtGe 2 film caused by the agglomeration. This could be responsible for the main contribution to the increase in R s and q c .

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