Quantitative thermal imaging with CCD array coupled to an heterodyne multichannel lock-in detection

Using thermoreflectance microscopy and a lock-in detection technique with a CCD camera, we have designed a system which is able to deliver quantitativ e submicronic thermal images. A careful choice of the illumination waveleng th permits to optimize the thermoreflectance signal and to highlight the he ating in chosen parts of the sample. A calibration conducted on various mat erials with a thermocouple delivers images of the absolute temperature of i ntegrated circuits working at frequencies between 0.25 Hz and 5 MHz, which allows for both static and dynamic characterization.