A method, system or the like which may, for example, be exploited as part of known methods, systems and/or apparatii which manipulate (i.e. tune, modify, change, create, etc.) the impedance of (integrated) semiconductor components or devices by exploiting a focused heating source. The method, system or the like exploits in situ optical measurements for the modification of the energy output of a focused heating source, such as for example of a (pulsed) laser heat source. The energy input to the focused heating source may be manipulated as a function of an optical measurement so as to obtain a desired or necessary energy output (e.g. target energy output) from the focused heating source.