本研究利用濺鍍製程製作多層富矽氧化物(Silicon-rich oxide, SRO)/二氧化矽(Silicon oxide, SiO2)與多層矽/石墨烯(Graphene)作為基板的聲子阻擋層，以阻絕聲子導熱，使矽成為可應用的熱電材料。
藉由Ｘ光繞射儀(High resolution X-ray Diffractometer, HRXRD)、穿透式電子顯微鏡(Transmission Electron Microscope, TEM)及X光光電子光譜(X-ray Photoelectron Spectrometer, XPS)等分析討論不同工作壓力下的的成膜形式，發現不論超晶格結構抑或奈米矽晶堆疊皆能有效降低熱導，而經由Hraman method的量測，由奈米矽晶堆疊的多層膜能取得較高的熱電優值，其ZTM 相較基板提高了10倍，印證多重量子點排列對於功率因數的提升。
藉由以石墨烯取代二氧化矽層，在P-type基板上可取得極高的熱電優值，但RC效應在此難以忽略，也顯示基板的選擇至關重要，在退火後其電導率可望進一步提升，進一步完成模組化的目標。

In our research, the multilayers of silicon rich oxide/silicon dioxide and silicon/graphene were synthesized by reactive magnetron sputtering. The multilayers act as phonon block for the silicon substrate. Our objective is the reduction of thermal conductivity with preservation of electrical conductivity and seebeck coefficient. The structural and physical properties of all multilayers were investigated by TEM, XRD, XPS, TDTR and Harman method. The thermal conductivity successfully drops to accessible range because of phonon scattering in each interface. The variation of proportion and working pressure shows that the existence of silicon nanocrystal might be a key point to preserve power factor. Relation between the formation of multilayers and figure of merit would be discussed. The figure of merit could further increase via replacing the single layer graphene with silicon dioxide. Although the electrical conductivity was still low, it could be further improved after annealing. The result shows the capacity of eco-friendly and low cost Si material with optimized thermoelectric nanostructure.

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