本研究主要使用快速退火製程以奈米鋁金屬誘發poly-Si，以獲得P型矽薄膜太陽能電池。相較於傳統爐管退火，快速退火的高升溫速率(10 °C/s)能在低溫、短時間提供熱能使a-Si誘發形成μc-Si；也因為結晶鋁本身表面能大於使產生矽結晶面(111)最小能量0.89 N/m，可提升矽結晶反應速率，同時鋁/矽介面矽原子能沿著鋁晶界的高能量擴散，在低溫快速退火就能獲得μc-Si。針對不同鋁膜厚度對誘發矽結晶的影響，發現退火前鋁膜厚度大於50 nm具有結晶性，並可降低結晶矽的退火溫度與時間，本文發現當退火熱壓應力達到臨界值，則矽會發生結晶化而與鋁膜厚度無關。鋁/矽介面存在原生氧化層時，鋁誘發退火應力(σan)需達臨界壓應力-380 MPa才能誘發a-Si形成結晶矽，由TEM分析也發現原生氧化層已造成μc-Al往a-Si擴散的阻障層。去除原生氧化層後也有助於結晶鋁提供a-Si在低溫、短時間結晶化，提升載子遷移率並降低鋁誘發退火熱應力(σan)臨界應力僅需達-295 MPa。
為了消除P型矽孔洞、減少載子濃度與增加載子遷移率，利用創新a-Si/c-Al/a-Si/SiO2/glass三明治結構，探討鋁膜、上下矽膜厚度與退火溫度，使結構未退火內應力(σ0)與退火過程內應力改變(σan-σ0)產生變化。未退火的高內壓應力有助於鋁膜形成細微多晶鋁晶粒並且促使結晶鋁退火過程的高速擴散；同時增加上下層矽膜厚度會增加內應力改變(σan-σ0)的壓應力而有害矽結晶化，而減少內應力改變(σan-σ0)的壓應力則有助於產生大尺寸微晶矽，得到高結晶效率與載子遷移率。適當的三明治厚度設計能使退火溫度低於400 °C，可應用於高效率矽薄膜太陽能P型電池。

In the research, the process of obtaining P-type Si thin film solar cells using the method of nano-aluminum-induced poly-Si under RTA was investigated. In contrast to conventional furnace annealing, RTA of high eating rate (10 °C/s) supply rapid thermal energy so that a-Si can be induced into μc-Si in a short time at low temperatures. The crystal Al may promote the crystallization reaction because its surface energy is higher than 0.89 N/m, which is the minimum energy required to produce the (111) orientation. Free Si atoms are iduced at the interface of the Al and Si sub-layers by the diffusion of Al alon the grain boundaries. The specimens with μc-Al (>50 nm) underwent Si crystallization at lower annealing temperature or time. Si crystallization started only when the compressive annealing stress (σan) of the composite film formed in the annealing process reached a critical value which is independent of the Al-film thickness. The critical stress for the onset of Si crystallizations is about -380 MPa. The absence of a native oxide layer also allowed Si crystallizations at a lower annealing temperature and a shorter annealing time, and increased the hall carrier mobility significantly. The critical stress required for Si crystallization for specimens prepared without a native oxide layer is about -295 MPa.
In order to eliminate the voids, reduced carrier concentration, and increased the hall carrier mobility of P-type Si, a-Si/nc-Al/a-Si/SiO2/glass sandwich specimens were prepared with various c-Al film thickness and two a-Si film thicknesses, and annealing temperature on the internal stress σ0 in the specimen before annealing and the internal stress change, (σan-σ0) during the annealing process for efficiency of Si crystallizations. A higher compressive σ0 is advantageous to form a finer c-Al grain size and promote a higher speed of nc-Al diffusions in the annealing process. Simultaneous increases in the thicknesses the first and third layers are harmful for the rise in compressive (σan-σ0) and thus Si crystallization. A lower compressive (σan-σ0) is helpful to create a larger µc-Si grain size. Good Si crystallizations and thus high carrier mobility are generally created by the specimen with a large c-Si grain size. Appropriate thickness designs for the sandwich structure can achieve high compressive σ0 and (σan-σ0), and thus high Si crystallizations even operating the annealing process as low as 400 °C. High-quality poly-Si is an essential material for high-efficiency thin-film solar cells.

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