TWI651852B - 電阻式記憶體 - Google Patents
電阻式記憶體 Download PDFInfo
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- TWI651852B TWI651852B TW105116649A TW105116649A TWI651852B TW I651852 B TWI651852 B TW I651852B TW 105116649 A TW105116649 A TW 105116649A TW 105116649 A TW105116649 A TW 105116649A TW I651852 B TWI651852 B TW I651852B
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- resistive memory
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- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 8
- 239000010931 gold Substances 0.000 claims description 5
- 229910052684 Cerium Inorganic materials 0.000 claims description 4
- GWXLDORMOJMVQZ-UHFFFAOYSA-N cerium Chemical compound [Ce] GWXLDORMOJMVQZ-UHFFFAOYSA-N 0.000 claims description 4
- 229910052746 lanthanum Inorganic materials 0.000 claims description 4
- FZLIPJUXYLNCLC-UHFFFAOYSA-N lanthanum atom Chemical compound [La] FZLIPJUXYLNCLC-UHFFFAOYSA-N 0.000 claims description 4
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims description 3
- 229910052737 gold Inorganic materials 0.000 claims description 3
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 claims description 3
- 229910052753 mercury Inorganic materials 0.000 claims description 3
- 229910052697 platinum Inorganic materials 0.000 claims description 3
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 3
- 229910052721 tungsten Inorganic materials 0.000 claims description 3
- 239000010937 tungsten Substances 0.000 claims description 3
- 239000010410 layer Substances 0.000 description 41
- 229910052760 oxygen Inorganic materials 0.000 description 14
- 239000001301 oxygen Substances 0.000 description 14
- -1 oxygen ions Chemical class 0.000 description 13
- 229910052787 antimony Inorganic materials 0.000 description 3
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 description 3
- 230000006378 damage Effects 0.000 description 3
- KJTLSVCANCCWHF-UHFFFAOYSA-N Ruthenium Chemical compound [Ru] KJTLSVCANCCWHF-UHFFFAOYSA-N 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000005684 electric field Effects 0.000 description 2
- 230000006870 function Effects 0.000 description 2
- 229910000449 hafnium oxide Inorganic materials 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 238000006722 reduction reaction Methods 0.000 description 2
- 229910052707 ruthenium Inorganic materials 0.000 description 2
- 229910052777 Praseodymium Inorganic materials 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- NRTOMJZYCJJWKI-UHFFFAOYSA-N Titanium nitride Chemical compound [Ti]#N NRTOMJZYCJJWKI-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 229910052797 bismuth Inorganic materials 0.000 description 1
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 229910000420 cerium oxide Inorganic materials 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000013500 data storage Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229910052735 hafnium Inorganic materials 0.000 description 1
- VBJZVLUMGGDVMO-UHFFFAOYSA-N hafnium atom Chemical compound [Hf] VBJZVLUMGGDVMO-UHFFFAOYSA-N 0.000 description 1
- WIHZLLGSGQNAGK-UHFFFAOYSA-N hafnium(4+);oxygen(2-) Chemical compound [O-2].[O-2].[Hf+4] WIHZLLGSGQNAGK-UHFFFAOYSA-N 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- AMGQUBHHOARCQH-UHFFFAOYSA-N indium;oxotin Chemical compound [In].[Sn]=O AMGQUBHHOARCQH-UHFFFAOYSA-N 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 229910052741 iridium Inorganic materials 0.000 description 1
- GKOZUEZYRPOHIO-UHFFFAOYSA-N iridium atom Chemical compound [Ir] GKOZUEZYRPOHIO-UHFFFAOYSA-N 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- BMMGVYCKOGBVEV-UHFFFAOYSA-N oxo(oxoceriooxy)cerium Chemical compound [Ce]=O.O=[Ce]=O BMMGVYCKOGBVEV-UHFFFAOYSA-N 0.000 description 1
- PUDIUYLPXJFUGB-UHFFFAOYSA-N praseodymium atom Chemical compound [Pr] PUDIUYLPXJFUGB-UHFFFAOYSA-N 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 229910052712 strontium Inorganic materials 0.000 description 1
- CIOAGBVUUVVLOB-UHFFFAOYSA-N strontium atom Chemical compound [Sr] CIOAGBVUUVVLOB-UHFFFAOYSA-N 0.000 description 1
- 229910052715 tantalum Inorganic materials 0.000 description 1
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 description 1
- 229910052727 yttrium Inorganic materials 0.000 description 1
- VWQVUPCCIRVNHF-UHFFFAOYSA-N yttrium atom Chemical compound [Y] VWQVUPCCIRVNHF-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N70/00—Solid-state devices without a potential-jump barrier or surface barrier, and specially adapted for rectifying, amplifying, oscillating or switching
- H10N70/20—Multistable switching devices, e.g. memristors
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C13/00—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00
- G11C13/0002—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00 using resistive RAM [RRAM] elements
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N70/00—Solid-state devices without a potential-jump barrier or surface barrier, and specially adapted for rectifying, amplifying, oscillating or switching
- H10N70/20—Multistable switching devices, e.g. memristors
- H10N70/24—Multistable switching devices, e.g. memristors based on migration or redistribution of ionic species, e.g. anions, vacancies
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N70/00—Solid-state devices without a potential-jump barrier or surface barrier, and specially adapted for rectifying, amplifying, oscillating or switching
- H10N70/801—Constructional details of multistable switching devices
- H10N70/841—Electrodes
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N70/00—Solid-state devices without a potential-jump barrier or surface barrier, and specially adapted for rectifying, amplifying, oscillating or switching
- H10N70/801—Constructional details of multistable switching devices
- H10N70/881—Switching materials
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N70/00—Solid-state devices without a potential-jump barrier or surface barrier, and specially adapted for rectifying, amplifying, oscillating or switching
- H10N70/801—Constructional details of multistable switching devices
- H10N70/881—Switching materials
- H10N70/883—Oxides or nitrides
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N70/00—Solid-state devices without a potential-jump barrier or surface barrier, and specially adapted for rectifying, amplifying, oscillating or switching
- H10N70/801—Constructional details of multistable switching devices
- H10N70/881—Switching materials
- H10N70/883—Oxides or nitrides
- H10N70/8833—Binary metal oxides, e.g. TaOx
Abstract
本發明揭示一種電阻式記憶體,用於解決習知電阻式記憶體之可靠度不佳問題,本發明之電阻式記憶體包含:一變阻層;及二電極層,分別結合於該變阻層,各電極層設有一摻雜區域,該摻雜區域含有重元素。藉此,可確實解決上述問題。
Description
本發明係關於一種電阻式記憶體;特別是關於一種在電極摻雜重元素的電阻式記憶體。
記憶體(Memory)廣泛的使用在各種電子產品上,隨著資料儲存需求與日俱增,對於記憶體容量以及性能的要求也越來越高,在各種記憶體元件中,電阻式記憶體(RRAM)具有極低的操作電壓、極快的讀寫速度以及高度的元件尺寸可微縮性等優點,有機會取代傳統的快閃記憶體(Flash Memory)以及動態隨機存取記憶體(DRAM),成為下個世代的記憶體元件主流。
習知電阻式記憶體具有二電極層及一電阻切換層,該電阻切換層設置於該二電極層之間,以形成金屬/介電/金屬(MIM)結構,該電阻切換層內部金屬絲可由電場控制氧化(oxidation)/還原(reduction)反應過程,切換該電阻切換層為低阻態(LRS)/高阻態(HRS),用以儲存兩種邏輯狀態(如:0或1)。
惟,習知電阻式記憶體在操作過程中,該電阻切換層的氧離子會移動,隨著操作次數增加,移動後的氧離子會逐漸對記憶體元件結構造成破壞,導致電阻式記憶體元件的可靠度不佳。
有鑑於此,上述先前技術在實際使用時確有不便之處,亟需進一步改良,以提升其實用性。
本發明係提供一種可提升元件可靠度的電阻式記憶體。
本發明揭示一種電阻式記憶體,可包含:一變阻層;及二電極層,分別結合於該變阻層,各電極層設有一摻雜區域,該摻雜區域含有重元素。
所述摻雜區域可鄰近該電極層與該變阻層之介面;所述該摻雜區域形成層狀;所述重元素可為鑭(La)、鈰(Ce)、鐠(Pr)、釹(Nd)、鉕(Pm)、釤(Sm)、銪(Eu)、釓(Gd)、鋱(Tb)、鏑(Dy)、鈥(Ho)、鉺(Er)、銩(Tm)、鐿(Yb)、鑥(Lu)、鉿(Hf)、鉭(Ta)、鎢(W)、錸(Re)、鋨(Os)、銥(Ir)、鉑(Pt)、金(Au)、汞(Hg)、鉈(Tl)、鉛(Pb)或其組合之群組;所述電極層可形成一多層結構。藉此,可利用該摻雜區域中的重元素防範該變阻層中的氧離子破壞元件結構,以提高元件可靠度及延長使用壽命。
上揭電阻式記憶體之電極層含有重元素構成的摻雜區域,用以防範該變阻層中的氧離子破壞元件結構,可確保阻態判讀正確,達到「提升元件可靠度」功效,可以改善習知電阻式記憶體之可靠度不佳問題。
〔本發明〕
1‧‧‧變阻層
2‧‧‧電極層
21‧‧‧摻雜區域
C1‧‧‧習知電阻式記憶體之電性曲線
C2‧‧‧本發明電阻式記憶體之電性曲線
第1圖:係本發明之電阻式記憶體實施例的組合剖視圖。
第2圖:係本發明之電阻式記憶體實施例與習知電阻式記憶體之電性曲線比較圖。
為讓本發明之上述及其他目的、特徵及優點能更明顯易懂,下文特舉本發明之較佳實施例,並配合所附圖式,作詳細說明如下:本發明全文所述之方向性用語,例如「前」、「後」、「左」、「右」、「上(頂)」、「下(底)」、「內」、「外」、「側」等,主要係參考附加
圖式的方向,各方向性用語僅用以輔助說明及理解本發明的各實施例,非用以限制本發明。
本發明全文所述之「重元素」,係指原子序不小於鑭(La,原子序為57)之元素,係本發明所屬技術領域中具有通常知識者可以理解。
請參閱第1圖所示,其係本發明電阻式記憶體實施例的立體組合圖。其中,該電阻式記憶體實施例可包含一變阻層1及二電極層2,該二電極層2分別結合於該變阻層1。
在此實施例中,該變阻層1可由二氧化矽(SiO2)或氧化鉿(HfO)等含氧絕緣材料構成,惟不以此為限;各電極層2可由導電材料製成,如:銦錫氧化物(ITO)或氮化鈦(TiN)等,各電極層2可構成單層或多層構造,各電極層2可設一摻雜區域21,該摻雜區域21可含有重元素,如:鑭(La)、鈰(Ce)、鐠(Pr)、釹(Nd)、鉕(Pm)、釤(Sm)、銪(Eu)、釓(Gd)、鋱(Tb)、鏑(Dy)、鈥(Ho)、鉺(Er)、銩(Tm)、鐿(Yb)、鑥(Lu)、鉿(Hf)、鉭(Ta)、鎢(W)、錸(Re)、鋨(Os)、銥(Ir)、鉑(Pt)、金(Au)、汞(Hg)、鉈(Tl)、鉛(Pb)或其組合之群組,使該電極層2形成佈置有重元素的三維空間範圍,用以防範該變阻層1中的氧離子破壞元件結構,該摻雜區域21可鄰近該電極層2與該變阻層1之介面,該摻雜區域21的重元素更可集中形成層狀,以提高阻隔氧離子之效果,以下僅以該摻雜區域21含有釓(Gd)為例說明,惟不以此為限。
請再參閱第1圖所示,本發明之電阻式記憶體實施例使用時,可於該二電極層2施加一外在電場(圖未繪示),用以驅動該變阻層1中的氧離子產生氧化/還原反應,使該變阻層1切換成不同阻態,如:高阻態(HRS)及低阻態(LRS)。值得注意的是,由於各電極層2含有重元素構成的摻雜區域21,隨著操作次數增加,若該變阻層1中的氧離子朝向該電極層2移動,則可藉由該摻雜區域21所含重元素之質量遠大於氧離子之
質量的特性,利用完全非彈性碰撞之原理,若被碰撞元素(重元素)之質量遠大於碰撞元素(氧離子)之質量,則重元素可吸收氧離子之動能,使電阻式記憶體元件結構不因氧離子的長期碰撞而損壞,進而提升元件可靠度及延長使用壽命。
請參閱第2圖所示,其係本發明電阻式記憶體實施例與習知電阻式記憶體之電性曲線比較圖。其中,習知電阻式記憶體(變阻層僅含氧化物)之電性曲線為C1,本發明電阻式記憶體實施例(變阻層1含氧化物及重元素Gd)之電性曲線為C2,參酌曲線C1、C2可知,經過一定次數操作後,習知電阻式記憶體之C1曲線的高、低阻態的電流值過於接近,容易造成阻態判讀錯誤,導致可靠度不佳;相較之下,本發明電阻式記憶體實施例之C2曲線的高、低阻態的電流值大幅分開,可確保阻態判讀正確,達到「提升元件可靠度」及「延長使用壽命」等功效,可以改善習知電阻式記憶體之可靠度不佳問題。
承上,本發明電阻式記憶體實施例之電極層含有重元素構成的摻雜區域,用以防範該變阻層中的氧離子破壞元件結構,可確保阻態判讀正確,達到「提升元件可靠度」功效,可以改善習知電阻式記憶體之可靠度不佳問題。
雖然本發明已利用上述較佳實施例揭示,然其並非用以限定本發明,任何熟習此技藝者在不脫離本發明之精神和範圍之內,相對上述實施例進行各種更動與修改仍屬本發明所保護之技術範疇,因此本發明之保護範圍當視後附之申請專利範圍所界定者為準。
Claims (5)
- 一種電阻式記憶體,包含:一變阻層;及二電極層,分別結合於該變阻層,各電極層設有一摻雜區域,該摻雜區域含有重元素。
- 根據申請專利範圍第1項所述之電阻式記憶體,其中該摻雜區域鄰近該電極層與該變阻層之介面。
- 根據申請專利範圍第1項所述之電阻式記憶體,其中該摻雜區域形成層狀。
- 根據申請專利範圍第1項所述之電阻式記憶體,其中該重元素為鑭、鈰、鐠、釹、鉕、釤、銪、釓、鋱、鏑、鈥、鉺、銩、鐿、鑥、鉿、鉭、鎢、錸、鋨、銥、鉑、金、汞、鉈、鉛或其組合之群組。
- 根據申請專利範圍第1項所述之電阻式記憶體,其中該電極層形成一多層結構。
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TW105116649A TWI651852B (zh) | 2016-05-27 | 2016-05-27 | 電阻式記憶體 |
US15/291,117 US9935265B2 (en) | 2016-05-27 | 2016-10-12 | Resistive random access memory |
CN201710089853.0A CN107437583A (zh) | 2016-05-27 | 2017-02-20 | 电阻式内存 |
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TW105116649A TWI651852B (zh) | 2016-05-27 | 2016-05-27 | 電阻式記憶體 |
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TWI651852B true TWI651852B (zh) | 2019-02-21 |
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US7205238B2 (en) * | 2004-10-21 | 2007-04-17 | Sharp Laboratories Of America, Inc. | Chemical mechanical polish of PCMO thin films for RRAM applications |
US7208372B2 (en) * | 2005-01-19 | 2007-04-24 | Sharp Laboratories Of America, Inc. | Non-volatile memory resistor cell with nanotip electrode |
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US7935957B2 (en) * | 2005-08-12 | 2011-05-03 | Semiconductor Energy Laboratory Co., Ltd. | Memory device and a semiconductor device |
US8817524B2 (en) * | 2011-07-29 | 2014-08-26 | Intermolecular, Inc. | Resistive random access memory cells having metal alloy current limiting layers |
US8890109B2 (en) * | 2012-12-20 | 2014-11-18 | Intermolecular, Inc. | Resistive random access memory access cells having thermally isolating structures |
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2016
- 2016-05-27 TW TW105116649A patent/TWI651852B/zh not_active IP Right Cessation
- 2016-10-12 US US15/291,117 patent/US9935265B2/en not_active Expired - Fee Related
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2017
- 2017-02-20 CN CN201710089853.0A patent/CN107437583A/zh active Pending
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US7205238B2 (en) * | 2004-10-21 | 2007-04-17 | Sharp Laboratories Of America, Inc. | Chemical mechanical polish of PCMO thin films for RRAM applications |
US7208372B2 (en) * | 2005-01-19 | 2007-04-24 | Sharp Laboratories Of America, Inc. | Non-volatile memory resistor cell with nanotip electrode |
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US9935265B2 (en) | 2018-04-03 |
CN107437583A (zh) | 2017-12-05 |
US20170346004A1 (en) | 2017-11-30 |
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