本論文中主要利用poly-GeSn(~5.1%Sn)來實現以HfZrOx (FE-HZO)為基礎的無接面鐵電薄膜電晶體(FE-TFT)應用於類神經計算的突觸元件，第一部份主要在比較poly-Ge跟poly-GeSn兩種通道材料對於HfZrOx鐵電材料的影響，從XRD、TEM、SEM、PFM以及SEM等物性分析poly-Ge、poly-GeSn以及HfZrOx的薄膜結晶品質，用電性量測的I-V曲線圖來萃取P-V磁滯特性曲線圖，並比較兩種通道材料的可靠度。
本論文第二部分是比較，NH3 plasma處理HfZrOx跟poly-GeSn的介面，改善介面間的缺陷，量測其閘極漏電流、電容電壓特性、磁滯特性曲線和可靠度量測，H跟N的自由基修補介面，有效提高Pr值並降低漏電流，提升可靠度。
本論文第三部分是比較，在HfZrOx跟poly-GeSn通道間加入不同絕緣層(Insulation layer, IL)，改善IL使可靠度提升，並量測長期可塑性(Long term plasticity, LTP)，短期可塑性(Short term plasticity, STP)，STDP等突觸元件特性，以及模擬其圖片辨識的準確率。
本次研究中，比較poly-Ge跟poly-GeSn兩種通道材料發現，因為poly-GeSn較低的熱膨脹係數引起較高的應力施加在HZO上，使得Pr值大於poly-Ge。在以poly-GeSn為通道材料的基礎上用NH3 plasma 處理通道跟氧化層之後H跟N的自由基修補介面間的懸鍵跟缺陷態，使domain pinning間少提高了Pr值。進一步在NH3 plasma處理的基礎上在poly-GeSn通道跟HZO氧化層中間加入Ta2O5的IL改善介面提升了在85℃下保持10年的可靠性，以及在同樣溫度下經過106操作Pr值仍維持在98%以上。在突觸元件特性的部分，電導具有的80個狀態，非線性的增強(αp)及抑制(αd)係數分別為-0.35和-0.22具有高度對稱性，電導的比值Gmax/Gmin也有9.8，以上的數據用於圖片辨識的訓練上，未來有望應用於3D IC及類神經計算上。

In this thesis, poly-GeSn (~5.1%Sn) is mainly used to realize the contactless ferroelectric thin film transistor (FE-TFT) based on HfZrOx (FE-HZO) applied to the synaptic component of nerve-like calculation. One part mainly compares the effects of poly-Ge and poly-GeSn channel materials on HfZrOx ferroelectric materials, and analyzes the film crystallization of poly-Ge, poly-GeSn and HfZrOx from XRD, TEM, SEM, PFM and SEM. Quality, electrical measurement of the I-V curve to extract the P-V hysteresis characteristic curve, and compare the reliability of the two channel materials.
The second part of this thesis is to compare the interface between HfZrOx and poly-GeSn in NH3 plasma, improve the defects between interfaces, measure the gate leakage current, capacitance voltage characteristics, hysteresis characteristic curve and reliable measurement, H and N. The free radical repair interface effectively increases the Pr value and reduces leakage current, improving reliability.
The third part of this thesis is to compare the insulation layer (IL) between HfZrOx and poly-GeSn channel, improve IL to improve reliability, and measure long term plasticity, short term plasticity, synaptic component characteristics such as STDP, and the accuracy of simulating its picture recognition.
In this study, the comparison of poly-Ge and poly-GeSn channel materials revealed that the higher thermal stress of poly-GeSn caused higher stress to be applied to HZO, making the Pr value larger than poly-Ge. On the basis of using poly-GeSn as the channel, the dangling bond and the defect state between the H and N radical repair interfaces after the channel and the oxide layer were treated with NH3 plasma, so that the Pr value was less increased between the domain pinning. Further, on the basis of NH3 plasma treatment, the addition of Ta2O5 in the middle of the poly-GeSn channel and the HZO oxide layer improves the reliability of the interface maintained at 85 ° C for 10 years, and at the same temperature, after the operation of 106, the Pr value is maintained. 98% or more. In the part of the synaptic element characteristics, the conductance has 80 states, the nonlinear enhancement(αp) and the suppression(αd) coefficient are -0.35 and -0.22, respectively, with high symmetry, and the conductance ratio Gmax/Gmin is also 9.8 or more. The data is used for the training of picture recognition, and it is expected to be applied to 3D IC and neural computing in the future.

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