Thermal characterization of epitaxial grown polycrystalline silicon

• The thermal conductivity of polycrystalline silicon layers was measured.
• It's mainly influenced by the layer thickness due to different grain sizes.
• The impurity concentration influences the anisotropic thermal conductivity.
• The recrystallization time increases the in-plane thermal conductivity.

The thermal conductivity of various epitaxial grown polycrystalline silicon layers was measured by using the 3-ω-method. Heater widths of 20 μm, 55 μm and 80 μm were structured applying standard photolithography. Experimental values are given, depending on layer thickness, ranging from 5 μm to 50 μm, the impurity concentration, the deposition temperature and recrystallization time. The measured values were used to discuss the cross-plane and in-plane thermal conductivity.