GOOGLE FIND
NAND的P/E循環次數有限
主流的25nm MLC閃存壽命是3000 -5000次
如今20nm級MLC NAND普遍不到3000次
TLC甚至不足1000次。
工藝越來越先進,NAND存儲密度越來越高,由於物理結構的原因其壽命也在降低,為此EMC的專家表示NAND需要新的繼任者,明年相變技術的PCM就會出現在市場上,它的速度更快,存儲密度更高,最關鍵的是可靠性也會更高
台灣旺宏電子 在本月的2012年IEEE國際電子設備會議(2012 IEEE International Electron Devices Meeting,IEDM)上他們會提交論文,披露他們對P/E次數達到1億次的自我修復NAND的研究。
實際上1億次壽命還只是目前得到的數據,帶隊的副處長Hang‑Ting Lue表示“實際上還真不知道(這種NAND)是否會壞,目前為止根本沒看到其壽命將近的信號。這個1億次壽命只是過去幾個月測試的結果。”
正常的NAND每次寫入數據都會擊穿一次隧道氧化層,這是一種物理損害,因此NAND壽命有限,熱處理可以修復這種損害,但是要想通過熱處理修復這種損害,那就需要在250 °C的高溫下持續數小時,目前來說這是不可能的。
這種NAND超長壽命的機理其實也藉用了PCM相變技術的某種原理,Macronix的工程師在研究PCM技術時發現其中使用的硫化玻璃(chalcogenide glass)到達熔點時會產生一種熱效應。最終他們發現這種效應對NAND也會起作用,因此他們重新設計了NAND的結構,有一個精細的加熱器可以加熱NAND的存儲單元。
=> 旺宏電子 ..有去申請專利嗎??
r3688ex wrote:
大陸新聞不知是真是假...(恕刪)
就怕是炒新聞放出來的鳥消息
再多觀察巴 不過國外大廠都沒有相關新聞推的話....
可信度不高喔
不是前幾天 再掏寶網
還有甚麼可用20年電池? 還有千年不衰退功能?
對於大陸新聞喔
我大多把它歸類等同YAHOO的新聞中的"新奇"就是了...
r3688ex wrote:
大陸新聞不知是真是假...(恕刪)
這個是真的喔,
那個IEEE IEDM研討會的節目流程檔案:
http://www.his.com/~iedm/program/2012_techprogram.pdf
其中第34頁:
9.1 Radically Extending the Cycling Endurance of Flash Memory (to > 100M Cycles) by Using Built-in Thermal Annealing to Self-heal the Stress-Induced Damage,
H.-T. Lue, P.-Y. Du, C.-P. Chen, W.-C. Chen, C.-C. Hsieh, Y.-H. Hsiao, Y.-H. Shih, C.-Y. Lu, Macronix International Co. Ltd.
就是他們這個技術的英文摘要。直接複制如下:
Flash memory endurance is limited by the tunnel oxide degradation after repeated P/E stressing in strong
electric field. Thermal annealing should be able to repair the oxide damage but such theory cannot be
tested in real time since completed device cannot endure high temperature > 400°C and long baking time
is impractical for real time operation. In this work, we propose and demonstrate a novel self-healing
Flash, where a locally high temperature (>800°C), short time (ms) annealing is generated by a built-in
heater. By modifying the word line (WL) from a single-ended to a double-ended structure, the WL can
carry a current to generate Joule heating; and the proximity of the gate can readily heat the tunnel oxide of
the Flash device, annealing out the damage caused by P/E cycling. We discover that a BE-SONOS
charge-trapping NAND Flash device can be quickly annealed within a few milliseconds. With this novel
technique, we demonstrate a record-high endurance of >100M (10 8 ) P/E cycles with excellent post-100M-
cycle retention. Interestingly, the WL heater can be used to achieve faster erasing although normally FN
tunneling should be temperature-independent. At the extreme temperature achieved in our heating-while-
erasing experiments electron de-trapping from the charge trapping nitride, accompanying hole FN
tunneling, also occurs, resulting in faster erasing. Finally, a novel design architecture for implementing
the self-healing Flash memory is proposed.
內文搜尋

X