- 學位論文
新型邏輯製程N通道接點耦合閘極多次寫入非揮發性記憶體
A New Logic Process N-Channel Contact Coupling Gate Multi-time Programmable Non-Volatile Memory Cell
摘要
摘要 隨著可攜式電子產品的蓬勃發展，內嵌式非揮發性記憶體的市場需求量大增，內嵌式非揮發性記憶體的開發逐漸受大家重視，其中，單一複晶矽浮動閘極非揮發性記憶體成為目前市場的主流，然而，目前已發展的單一複晶矽閘極非揮發性記憶體大多有著元件浮動閘極耦合率過低，導致在元件操作上受到許多限制。本論文提出一新型N通道接點耦合閘極多次寫入非揮發性記憶體，在標準邏輯製程下，藉由耦合接點結構來提升元件對浮動閘極的耦合能力。 新型N通道接點耦合閘極多次寫入非揮發性記憶體採用單一複晶矽閘極架構，寫入操作以通道熱載子轟擊引發熱電子注入，與利用Fowler-Nordheim穿遂效應進行抹除操作，可以多次性寫入與抹除。此新型元件可在50ms內完成寫入操作，抹除時間則為150ms，再者元件的耐久度可達10K次，資料保存性在125oC下達1000小時以上的考驗。基於耦合接點的特性，此元件不需額外的耦合井即可進行電性抹除，在陣列運用上也不需要額外的選擇閘極，因此有著極小的細胞尺寸，很適合應用於高密度的記憶體陣列。此新型元件擁有良好的操作特性與資料可靠度，與極小的細胞尺寸，提供內嵌式非揮發性記憶體一個新的選擇與應用。
關鍵字
邏輯製程多次寫入非揮發性記憶體並列摘要
bedded nonvolatile memory (eNVM) are growing fast, and single poly floating gate eNVM is the mainstream in the market. However, single poly floating gate eNVM has faced the challenge that the coupling ratio of the floating gate is too small, result in the difficulties in cell operation. This study proposes a new N-channel contact coupling gate multi-time programmable non-volatile memory cell. By adding multiple coupling contacts, the coupling ratio of the floating gate can be improved without additional process step and extra masking. The new N-channel contact coupling gate multi-time programmable non-volatile memory cell is single poly and stores charge in floating gate by channel hot electron injection, and erases by Fowler-Nordherim tunneling. The program time is within 50s, erase time is within 150ms, endurance is up to 10K and the cell has been verified to pass the criteria after 1000 hours of retention bake at 125oC. The contact coupling’s characterization needs neither another coupling well served as an erase gate nor a select transistor in array operation. Therefore, an ultra small cell size has been demonstrated and suitable for high density application. The new cell has good operation performance, high reliability, and ultra small cell size, so it will be a promising new solution for eNVM applications.