研究目的
Investigating the cross-plane thermal properties of ALD Al2O3/ZnO superlattice films with improved figure of merit and their cross-plane thermoelectric generating performance.
研究成果
The study successfully measured all cross-plane thermoelectric properties of Al2O3/ZnO superlattice films, demonstrating a significant advancement in understanding phonon and electrical transports in nanostructured materials. The 6-cycled AO/ZnO superlattice films showed the best performance with a ZT value of ~0.45 at 500 K, attributed to the suppression of thermal conductivity and enhancement of the Seebeck coefficient.
研究不足
The study focuses on the cross-plane properties of Al2O3/ZnO superlattice films, and the experimental setup may not be directly applicable to other types of superlattice films without modification. The temperature range is limited to 80 to 500 K.
1:Experimental Design and Method Selection:
A novel technique using a structure of sandwiched superlattice films between two embedded heaters as a heating source and electrodes with two Cu plates was employed for direct probing of cross-plane Seebeck coefficients and electrical conductivity. The cross-plane four-point-probe 3-ω method was used for thermal conductivity measurements.
2:Sample Selection and Data Sources:
Four different AO/ZnO thin films were prepared by sequential alternating of 1, 3, 6, and 9 ALD cycles of trimetylaluminium (TMA) and Diethylzinc (DEZ) pulses.
3:List of Experimental Equipment and Materials:
Atomic layer deposition (ALD) system, high-resolution transmission electron microscopy (HR-TEM), spectroscopic ellipsometry, Pt coil heater, K-type thermocouples, CompactDAQ with LabVIEW software.
4:Experimental Procedures and Operational Workflow:
The cross-plane Seebeck coefficient and electrical conductivity were measured in the temperature range from 80 to 500 K. The thermal conductivity was measured using the 3-ω method in the same temperature range.
5:Data Analysis Methods:
The Wiedemann–Franz law and the modified Callaway model were used for theoretical analysis of the thermal conductivity.
独家科研数据包,助您复现前沿成果,加速创新突破
获取完整内容