快閃記憶體元件在經過多次的寫入/擦拭操作之後，主要的元件傷害都集中在熱電子穿隧閘極氧化層的過程中發生。當元件使用愈久，其閘極氧化層的傷害便愈嚴重；如此一來，將使得電子無法穿隧閘極氧化層到達懸浮閘極進行資料的儲存，也將使得快閃記憶體的電荷保持能力大幅衰減，導致元件無法使用。因此，本篇論文探討以單層/堆疊閘極結構做為快閃記憶體中的穿隧閘極介電層，再配合不同的快速熱退火溫度條件，對於快閃記憶體元件電特性之影響，做一系統性的探討。
由實驗結果可發現，堆疊結構不論在寫入或是擦拭方面，其穿隧電流值皆比單層結構大，因此，堆疊結構有較快的寫入及擦拭速度；在可靠度測試中，實驗結果顯示出堆疊結構不論在電荷保持、耐力表現、讀取干擾方面，其整體表現皆比單層結構優越。而在同樣是堆疊樣本當中，我們發現當墊氧化層厚度愈薄，跨於閘極氧化層的電場便愈大，因此可得到較大的穿隧電流值，所以墊氧化層較薄的元件擁有較優越的寫入/擦拭特性；而墊氧化層厚度較厚的樣本，則是在高電場下的電荷保持特性，表現較為出色。在退火溫度方面，由實驗結果發現當退火溫度在850℃之下，材料擁有最佳的特性，因此有較佳的元件特性。整體而言，我們認為OH15/60-850為最佳的元件參數。

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