For a thermal flux set to 10mW(i.e. flux density of 62 kWm^-2), the thermal resistances Rsam are established for different thermal conductivities(from 0.8 to 20W(m^-1)(K^-1)) in case of different sample thicknesses b (up to 300 micrometer). The network obtained(figure 9) is then used to determine the thermal conductivity as a function of the sample thickness and the thermal resistance measured.