近年來，隨著科技的進步，電子產品越來越普及，除了軟體與演算法的進步，硬體上的支援當然是不可或缺的，並需要有更大的儲存空間，用以支援軟體。無論是揮發式記憶體亦或是非揮發式記憶體絕對都在積體電路系上必須且重要的模組。搭配積體電路製程技術上的進步，得以達到元件尺寸微縮，使記憶體密度可以提高並有較大的儲存空間。然而，微縮尺寸的同時也帶來了許多挑戰，像是較大的漏電流、高電壓、高電場等，都需要進一步研究討論並提出解決方案。
目前，非揮發式記憶體又以快閃記憶體為現在的主流技術，本論文將討論NAND型快閃記憶體中胞間空隙對元件特性的影響。胞間空隙的設計，利用較低的介電常數，降低字元間的電容，以達到降低字元間干擾效應。本論文將研究討論的主軸分為兩部份，第一部分為藉由模擬，分析特性受到胞間空隙設計的影響，另一部分則以實際元件量測結果，了解結構設計如何造成對元件可靠度的變化。
透過元件模擬軟體，模擬不同胞間空隙大小對側向電場和直接電場所造成之影響，並搭配1X奈米NAND型快閃記憶體作為量測元件，利用不同厚度的氧化層，將具有不同大小的胞間空隙進行實際元件量測分析。

同時，研究胞間空隙所可能引發的各項優缺點加以分析與討論。另外，針對可靠度部分，主要探討為不同的胞間空隙大小對耐久度的影響，分別以三種比例的胞間空隙，進行寫入抹除循環的壓力測試，藉此分析其對循環壓力的耐久度，並發現次臨界擺幅與串接電阻亦會受到胞間空隙結構的影響。

With the advancement of technology, electronic products become more pervasive in our daily lives. Besides software and algorithm improvement, the improved hardware in electronic hardware, most ICs, are indispensable. We need bigger capacity in data storage to support more sophisticated software functions. Both volatile memory and non-volatile memory play important roles. Aggressive scaling of VLSI technologies enables higher data storage capacities in a much compact solid-state ICs. However, these advanced memories chip face several challenges as devices scale down, like larger leakage current, higher voltage, and higher electron field.

Nowadays, flash memory technology is a mainstream memory for data and code stored in portable electronics. Using lower dielectric constant make the capacitance in the word line are commonly used to reduce interference between adjacent cells on 2D NAND Flash cells.

In this thesis, the impact on airgap design on 2D NAND array is investigated by device simulation and actual measurement results on test samples with different airgap designs. Through device simulator, the influent of the direct field and fringe field with different airgap size can be clarified. Measurement data on 1X nm NAND Flash devices further provide evidence to support the effect on device reliability by samples with different air-gap structures. Degradation on the subthreshold swing and the string resistance due to cycling stresses are also found to depends slightly on air-gap structures.

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