Typical Applications

Abstract

Some applications of Lock-in Thermography for the investigation of a thermally thin sample (solar cell) and a thermally thick one (IC) were already presented in the examples given in Chap. 5. In the following section we will present some more applications, showing the universal applicability of this technique to different fields of functional diagnostics of electronic components. At the beginning of each section, the physical problem to be solved will briefly be introduced. Of course, also this can only be a small survey of the possibilities of lock-in thermography in this field. Not considered here will be the applications belonging to the fields of non-destructive testing (NDT, see [2]) and of biology and medicine (see, e.g., [89]). In Sect. 6.1 some more investigations of integrated circuits (ICs) will be described, since this may become one of the most promising applications of lock-in thermography in future. Especially, we will present an application of a more sophisticated triggering mode of imaging sites of a definite logical response of an IC, which was mentioned in Sect. 2.3. Moreover, we present an example of a lock-in thermography investigation from the back-side on an encapsulated chip “through the die” . In Sect. 6.2 some more examples of solar cell and solar module investigations will follow. It will be shown that the interpretation of lock-in thermograms of single solar cells differs somehow from that of solar modules, which consists of an electrical serial and parallel connection of several solar cells. Here, we also will present results of a quantitative evaluation of lock-in thermography results in terms of the measurement of the current across several shunt types. Section 6.3 will demonstrate the use of lock-in thermography for investigating gate oxide integrity defects (GOI defects) in MOS devices. Finally, in Sect. 6.4 some examples of investigation of bonded semiconductor wafers are introduced and discussed.KeywordsSolar CellForward BiasSolar ModuleMaximum Power PointAmplitude ImageThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.