由於平面式元件微縮面臨挑戰，3D快閃記憶體技術變得越來越重要。記憶體元件除了追求高儲存密度之外，同時保有良好的電性特性以及可靠度的元件是被期待的。由於近年來矽化鍺和鍺掩埋式通道被應用於快閃記憶體之操作特性提升，本論文首先以鍺沉積層提供較多的載子注入、降低氧化層能障等性質改善元件操作特性。同時，將矽化鍺和鍺沉積層摻雜了磷和硼，以觀察不同通道介面的內建電場來分析其對元件操作特性的影響，最後探討利用電荷反轉式元件改善無接面式元件抹除速度上的缺點。
第一部分，將矽化鍺及鍺沉積層掩埋通道應用在多晶矽無接面快閃記憶體元件上。而從實驗結果得知，矽化鍺和鍺的掩埋通道元件在寫入速度和抹除速度上相較於無掩埋式通道都有較好的表現。這可歸功於鍺材料的特性，較窄的能隙可以提供較多載子、穿隧層電場較強，穿隧層能障也較低，電子跨越能障相對容易。再者，矽鍺及鍺掩埋通道元件的耐久力也相較好，可能因為較快的寫抹速度，也就是較短寫入時間下減少了氧化層的損傷。
第二部份，針對矽化鍺及鍺掩埋通道摻雜磷和硼，讓沉積層與通道產生PN接面和內建電場。原本預計觀察對沉積層進行摻雜後接面處所產生內建電場的效應，但後來發現鍺穿隧層的厚度才是占有較主要的影響原因。從實驗結果來看，鍺穿隧層較厚的元件有著較快的寫抹速度、良好的元件耐久力。內建電場機制之影響不大，能障較低才是影響操作特性的主要原因。
第三部分，探討掩埋式通道中摻雜磷和硼反轉式通道元件，由前一部分得知氧化鍺穿隧層越厚寫抹速度越快，但無接面式快閃記憶之元件之抹除速度較緩慢，因此採用反轉式元件。而根據實驗結果，電荷反轉式元件在抹除速度和元件耐久力也有所提升。

3D flash technology is becoming more important, because the scaling down planar device faces challenge. In addition to high storage density, flash device with good electrical characteristic and reliability are required. In recent years, buried channel such as SiGe and Ge deposition layer applications are applied used to improve operation characteristics of flash device. Therefore, in this thesis, operation characteristics of device are improved by Ge buried channel, which can provide more injection carriers and lower energy barrier height. Operation characteristic of devices with different build-in electric field near channel and tunneling oxide interface formed by P/B doping junction are analyzed and discussed. Finally, erase speeds of flash device are enhanced by inversion mode device are compared to junctionless.
In the first part, SiGe and Ge deposition buried channels are applied to poly silicon junctionless flash memory device. From experiment result, program and erase speeds of devices with SiGe and Ge buried channels are faster than those without buried channel device. This improvement can be attributed to Ge with more injection carriers by a narrower bandgap, high electric field in tunneling layer, and lower energy barrier. In addition, endurance performance of SiGe, Ge buried channel device are good because of fast program speed, namely shorter program time which reduces the damage in tunneling oxide layer.
In the second part, SiGe/Ge buried channels are doped with phosphorus and boron to forms PN junction and create a built-in electric field. Although in effects of built-in electric field of PN junction formed with different doping are expected, the thickness of GeO2 in the dominant faster than our observation. From experiment at result, device with a thicker GeO2 shows faster program/erase speed and good endurance performance. Effects of the built-in electric field are minor, because operation characteristic are influence by the tunneling path.
In the third part, IM flash memory device with Ge buried channel and P/B doping is studied, the program/erase speeds of devices with more GeO2 are faster and junctionless flash memory device has slower erase speed. From experiment at result, the IM device shows faster erase speed and good endurance performance.

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