本研究利用脈衝雷射沉積技術，常溫下沉積碲化鎵奈米薄膜，透過後續退火處理，
可以在碲化鎵奈米薄膜之介面析出第二相(碲)，形成多種不同形態的週期性排列之碲化 鎵/碲奈米複合結構，進而大幅改善其熱電性質。透過本研究可得到以下五個結論(1)藉 由退火溫度及時間的精準控制，在主相碲化鎵之奈米區塊間隔中，可設計出點對點單晶 碲橋樑(200 oC)、完整填充(225 oC)及部分填充(250 oC)單晶碲河流等第二相網絡狀形貌。
(2)此析出之第二相(碲)可作為導電載子傳輸時的全新通道，使得遷移率大幅提升，進而 改善導電率，且不同形態之奈米複合結構對遷移率影響亦不同，完整填充之河流結構的 遷移率最佳，部分填充之河流結構次之，點對點碲橋梁再次之。(3) 若改變第二相(碲) 之介面析出含量，則有機會控制此奈米複合結構之 Seebeck 係數。(4)退火處理可有效提 高碲化鎵/碲奈米複合結構之載子濃度，但退火時間若過長，則會導致其降低。(5)未來 此技術可應用在 Seeebeck 係數優良，但導電率較低之碲化物熱電材料系統，利用此一技 術析出第二相形成奈米複合結構，進行介面修飾，從而達到大幅提升導電率之可能性。
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