鍺奈米晶體之金氧半電容在不同穿遂層之分析

The analysis of Germanium embedded in Metal-Oxide-Semiconductor Structure with different tunneling layer

楊章良(Zhang-Liang Yang)

指導教授 ： 管傑雄

國立臺灣大學/電機資訊學院/電子工程學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.01378

摘要

為了增加非揮發性記憶體的存電效果，我們使用了兩種方法，第一種是使用奈米粒子，我們使用了鍺奈米粒子，電荷不是儲存在連續多晶矽浮動閘極，而是儲存在一層互相獨立，隔絕的結晶化的奈米晶體或奈米點來降低傳統快閃記憶體所遭遇電荷流失的問題，第二種我們使用了氮化矽來當作穿遂氧化層以利載子電荷的傳輸，為了增加記憶效果，來增加存電的電荷量，之後我們把這兩種優點整合在同一個元件上面以利記憶體的存電效果。
接著我們利用一些實驗方法來證明此種穿遂層為氮化矽元件的缺陷，會比穿遂層為二氧化矽元件來的多，我們利用直流訊號、交流訊號、拉曼頻譜分析儀等儀器來驗證，此種穿遂層為氮化矽元件具有較多的缺陷分佈，且具有較好的存電效果。
本論文中我們利用交流訊號的電導值，提出一個缺陷的模型來驗證，其中包含了載子交換時間常數，和缺陷密度常數，根據以上這些實驗來驗證氮化矽的元件具有較多的缺陷可以用來幫助載子電荷傳輸到鍺奈米粒子，以達增加元件儲存電荷的效果。

關鍵字

氮化矽 ； 鍺奈米晶體 ； 拉曼 ； 遲滯曲線 ； 陷阱電容 ； 陷阱電導

並列摘要

In order to improve the charge effect of non-volatile memory, we use the germanium nano-crystals (Ge NCs) and Si3N4 in order to improve the charge storage characteristic . Among the nano-crystals (Ge NCs),the charge are not storage in the continue floating-gate. Instead the charge are storage in the isolated germanium nano-crystals to avoid the charge loss of non-volatile memory. we use the Si3N4 as the tunneling layer to improve the charge amount of device . Afterwards we use the two advantage to fabricate the device.
The device to be fabricated, we introduce some method to demonstrate that the Si3N4 as tunneling layer has more trap density than the SiO2 as tunneling layer. We use dc current ,ac current and Raman spectrum to analyze the germanium nano-crystals and to demonstrate the trap density of Si3N4 as tunneling layer can improve the charge characteristic. The direct current versus time can indirect to match our trap theory .The charge storage characteristics of our samples are investigated with the C-V hystereses. The frequency-dependent C-V and conductance-voltage (G-V) experiments are further introduced to study the interface traps and the traps induced by the NCs formation. According to these experiment , we make use of the Characteristic time constant and trap density A to verify that the trap of Si3N4 as tunneling layer can help the carrier transport to the germanium nano-crystals and to gain the charge storage of the device.

並列關鍵字

Si3N4 ； Ge NCs ； Raman ； hysteresis curve ； trap capacitance ； trap conductance

參考文獻

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