Measurement of thermal properties of thin dielectric films and anisotropic solids by ac hot-strip method

Specific heat and heat conductivity of BaTiO3polycrystalline films in the thickness range 20–1100 nm

“…It was revealed that for the condition h f << d p << h s (here h f is the thickness of the film, d p thermal waves penetration depth (d p = (λ s /2c s ω) 1/2 , λ s , c s heat conductivity coefficient and specific heat of a substrate), h s the thickness of the substrate), important asympthotic relation can be obtained for the ratio of the complex temperature oscillations of the probes deposited on the film and on the substrate (Figure 1). This ratio has a form [26]…”

“…Our experimental setup was described in [26] in full detail. The experimental errors of measurements of c f and λ f at the temperature range of 300-400 K was estimated as 3-5% and 2-3% for lower temperatures; the film thickness variation was 20-1100 nm.…”

“…Recently we have shown that ac-hot probe method can be successfully applied for the thermal characterization of thin dielectric films deposited on the massive substrate [25][26]. The basic idea of the heater-probe method is that a metal strip or wire made of a metal with high thermal resistivity coefficient serves as a source of heat and a temperature sensor simultaneously.…”

“…These oscillations can be measured using temperature dependence of the probe resistance. The temperature and This ratio has a form [26] δT f /δT s = 1…”

“…For BaTiO 3 thin films a fused 5 quartz and a crystalline sapphire can be accepted as substrates satisfying the mentioned conditions. Our experimental setup was described in [26] in details. The final accuracy of the measurements of c f and λ f at the temperature region 300-400 K was estimated as 3-5% and 2-3% for lower temperatures; film thickness variation was 20 -1100 nm.…”