Emissivity measurements on electronic microcircuits

An analytical comparison of the accuracy of the most often used methods of emissivity measurements carried out during infrared thermographic studies on electronic microcircuits (thin-, thick-film and hybrid ones, high-density miniature PCBs, microsystems) is the main purpose of this paper. A typical measurement arrangement applied to these studies and main factors influencing the measurement results are presented. A special relationship describing the thermographic camera signal has been formulated. Conventional and unconventional methods of the emissivity measurements together with a detailed analysis of the accuracy of typical methods are presented in the paper. A criterion and a procedure of choosing the emissivity measurement method are also proposed. Similar problems concerning the temperature measurements will be presented and discussed in the next paper.