Normally, heating up a glass or Si substrate with thin metal strips while measuring the resistance (RT) in these metal strips at certain temperature intervals (T) yields directly a linear relation, which can be fitted with RT/R0=1+αT−T0 [64], in which α is the the temperature coefficient of resistance (TCR) value. The thin-film TCR values have to be measured as they differ from the bulk TCR values due to its dependency on layer purity, grain size, and deposition method [65,66]. Belser and Hicklin also lists other attributes, such as surface roughness, porosity, and adsorbed materials present in or on the substrate which could influence the TCR value [64]. The bulk TCR values are 0.0034 K−1 and 0.0037 K−1 for Au and Pt [67].