TW412739B - Rewritable optical information medium - Google Patents

Rewritable optical information medium Download PDF

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TW412739B
TW412739B TW087119177A TW87119177A TW412739B TW 412739 B TW412739 B TW 412739B TW 087119177 A TW087119177 A TW 087119177A TW 87119177 A TW87119177 A TW 87119177A TW 412739 B TW412739 B TW 412739B
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layer
thickness
optical information
information medium
patent application
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TW087119177A
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Guo-Fu Zhou
Bernardus Antonius J Jacobs
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Koninkl Philips Electronics Nv
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    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/252—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers
    • G11B7/258—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of reflective layers
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/242—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers
    • G11B7/243—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising inorganic materials only, e.g. ablative layers
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/252—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers
    • G11B7/257—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of layers having properties involved in recording or reproduction, e.g. optical interference layers or sensitising layers or dielectric layers, which are protecting the recording layers
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/242—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers
    • G11B7/243—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising inorganic materials only, e.g. ablative layers
    • G11B2007/24302—Metals or metalloids
    • G11B2007/24312—Metals or metalloids group 14 elements (e.g. Si, Ge, Sn)
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/242—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers
    • G11B7/243—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising inorganic materials only, e.g. ablative layers
    • G11B2007/24302—Metals or metalloids
    • G11B2007/24314—Metals or metalloids group 15 elements (e.g. Sb, Bi)
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    • G11B7/243—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising inorganic materials only, e.g. ablative layers
    • G11B2007/24302—Metals or metalloids
    • G11B2007/24316—Metals or metalloids group 16 elements (i.e. chalcogenides, Se, Te)
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    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
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    • G11B7/002—Recording, reproducing or erasing systems characterised by the shape or form of the carrier
    • G11B7/003—Recording, reproducing or erasing systems characterised by the shape or form of the carrier with webs, filaments or wires, e.g. belts, spooled tapes or films of quasi-infinite extent
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    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
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    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
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    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
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    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/252—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers
    • G11B7/253—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of substrates
    • G11B7/2533—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of substrates comprising resins
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    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/252—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers
    • G11B7/253—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of substrates
    • G11B7/2533—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of substrates comprising resins
    • G11B7/2534—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of substrates comprising resins polycarbonates [PC]
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    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/252—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers
    • G11B7/258—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of reflective layers
    • G11B7/2585—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of reflective layers based on aluminium
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/252—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers
    • G11B7/258—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of reflective layers
    • G11B7/259—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of reflective layers based on silver
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/252—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers
    • G11B7/258—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of reflective layers
    • G11B7/2595—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of reflective layers based on gold
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S428/00—Stock material or miscellaneous articles
    • Y10S428/913—Material designed to be responsive to temperature, light, moisture
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S430/00—Radiation imagery chemistry: process, composition, or product thereof
    • Y10S430/146—Laser beam
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12674—Ge- or Si-base component

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  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Optical Record Carriers And Manufacture Thereof (AREA)
  • Thermal Transfer Or Thermal Recording In General (AREA)

Description

五、發明說明（υ 本發明係關於一種利用雷射光束供高速記錄之可重寫式 光學資訊媒體，該媒體包含一具有疊合層之基材，該疊合 層依順序包含，第一介電性層，由含有鍺，銻與篩之合金 所組成之相變化材料記錄層，第二介電性層與金屬鏡面_ 層。 本發明亦係關於應用此類光學記錄媒體於高儲存密度與 高速率數據應用。 以相變化原理為基礎之光學資訊或數據儲存吸引人之 處，乃因為其結合了直接'複寫（DOW )與高儲存密度且易 於與唯讀系統相容之可能性。相變光學記錄包含利用雷射 光束聚焦在一結晶薄膜中形成次微米尺寸化之非晶系記錄 標記。於記錄資訊期間，相對於依據擬記錄資訊而調變之 被聚焦雪射光束，媒體因以移動。因此，相變記錄層發生 遽冷且引起非晶系資訊位元形成於記錄層之爆光區域而其 未曝光區域仍維持為結晶。被寫過標記之拭除係經由相同 雷射予以加熱而實施再結晶。非晶系標記代表數據位元， 其可藉以低電能聚焦之雷射光束在基材上予以複製。相對 於結晶記錄層之非晶系標記之反射差造成雷射光束之調 變，其接著經由轉換器按照被定碼，記錄之數位資訊轉變 為調變之光電流。 高遠相變光學記錄之主要問題係對拭除（再結晶）速度 之要求。於諸如碟形DVD-RAM與光學記錄帶之高密度記錄 與南迷牛數據應周方® !特別需求南，¾吉晶速度1其中完全 結晶時間（完全拭除時間：CET )必須短於50毫微秒=若
4im9
五 '發明說明（2) 結晶速度相對 前記錄之舊數
^ 光束無法與媒體之線性速率匹配，先 W §4晶系標記）不能於dow期間被完3全移 去（再結晶）^此將引起南雜訊位準 在公開文件中所論及之光學資訊媒體之類型可由气國專 利US 5, 191，565習知。習知之相變型媒體包含依序=第Z 介電性層，鍺-銻-鎊相變合金記錄層，第二介電性層.與舍 屬反射層之圓碟形基材疊合層組成。此類疊合層可二^薛 為IPIM結構，其中Μ代表反射或鏡面層，I代表，介 =^ '而 Ρ代表相變記錄層。該專利揭示於三元組合，物圖（圖^ a) 中位於計置化合物G e s b2 T q之脈衝時間為5 0毫微秒，在该 脈衝時間下鍺-銻-篩組合物開始結晶。此時間不等於完金 拭除時間CET，而較短。完全拭除時間CET被定義為依^計 #I測得之於結晶環境下使被寫過之非晶系標記完全結晶 之拭除脈衝之最小時'間。為完全栻除非晶系標記，必須經 成核與紋理（晶種）成長兩種製程。於該專利所論及之時 間係成核日rr間’.即第一個晶種可被觀察到之時間。完全孩 除，即非晶系標記之完全結晶，另外耗費十或更多毫微 秒。該專利指導於三元圖中GeSb2Te4連結線之組合物一更迅 速地結晶。例如計量化合物GeSb2Te4(原子量百分比3 Sb2S,6Te57.!)即顯示具有4〇毫微秒之成核時間。由本索申請 人之實驗顯示此化合物具有5 3毫微秒（CET。 本發明之目的係特別提供了 一可重寫式光學資訊嫔體， 其係適合於具有50毫微秒或更歡CET值之諸如…卜Ram與类 學記錄磁帶之高速光學記錄。在本文中高速記錄可被解釋
第6頁 五 '發明說明（3) 為相對於* ^ 據CD雷射=y光求之媒體之線性速率至少為7 2 m/ s，才 定之裎度：片之標準為六倍速度。媒體之跳動應在低而穩 itt g ήίι 予以達成，、Ϊ依據本發明藉所描述之公開光學資訊媒體而 物區域所定Ϊ特徵為記錄層包含具有鍺_銻~錄三元圖組合
Ge^-2Sb25.8Te6〇 Ge«^Sb27.3Te60 Gei“Sb292Te57 Geis. l Sb27 8 Te5? Gei3.2Sb26 4 Te6〇 第一介電 有以下諸馆義之依原子百分比之組合物合金’該區域係呈 . 卜者頂點之五邊形： ^ (P) (Q) (R) (S) (T) ； 么 性層具有厚度70至（70+ λ/2η )毫微米，其 _ 中λ係雷射光束之波長，而^係此層之折射率； —一記錄層具有厚度10至35毫微米； ---第二介電性層具有厚度丨〇至5〇毫微米； 金屬鏡面層具有厚度60至160毫微米。 令人驚訝地，於鍺-銻-篩之三角三元組合物圖令（參考 圖1 )在五角區域PQRST内之合金顯示50或較短 > 或甚至 45毫微秒以下之CEΤ。此等合金之組合物係位於連接組合 物GeTe與Sb2Te4之連結線之左側，且比在此連結線上之虛 擬（pseudo)二元化合物GeSb2Te4顯示較短之CET值。此與上 述美國專利相反，該專利指導自連結線GeTe-Sb2Te3分離時 成核時間將自组合物GeSb2Te4之40毫微秒增加至位於該線
第7頁 五、發明說明（4) 左側合金之50毫微秒或更多。在PQRST區域外之CET值超過 5 0毫微秒。 特別有用之合金具有之組合物如下： (GeSb2Te4 ) > 其中莫耳分率x滿足：〇.〇1<x<〇.37。 此等組合物係位於在三元组合物圖中連接T e與G e Sb2 T e4 之連結線上，但係在五角區域PQRST之内。於圖1中之頂點 相當於X = 0. 37 之Get3 2Sb 26 4Te6Q 4 組合物。 根據本發明之另一精製媒體之X值滿足：0 . 0 2 S X S 0, 35。在此等X值下，可獲低於45毫微秒之CET值。 滿足此化學式之組合物實例係具有4 2毫微秒之CE T之 GeN.05Sb28.15Te57.80 (x =0. 10 )，與具有 4 3 毫微秒之C ET 之 G e13.75 S b27.4。T e58.叼(x 0 . 2 2 )。 第一介電性層，即介於基材與相變化記錄層之間層*保 護記錄層免於遭受溼氣及保護基材免於遭受熱破壞，且使 光學對比最佳化。為使跳動達最低化，第一介電性層之厚 度較佳至少為7 0毫微米。由於光學對比之故，此層之厚度 被限制於（70 +又/2n )毫微米，其中；I係雷射光束之波 長，而η係第一介電性層之折射率。 ‘ 前述鍺-録-I帝合金之C Ε Τ值係視記錄層之層厚度而定。 若層厚度增加高達1 0毫微米則CET迅速地減少，若發生層 厚度進一步增加，則其值達到5 0毫微秒或更少。當記錄層 係比2 5毫微米厚時，CET本質上即不受厚度之影響。在3 5 毫微米以上媒體之循環使用能力即相對地受影響。媒體之
第8頁 五、發明說明（5) 循環使用能力係在例如1 〇5之大量DOW -循環之後，由光學 對比之相對變化所測得。於每一次循環中被寫過之非晶系 位元經雷射光束加熱予以再結晶而被拭除而新的非晶系標 §己則被寫入。於理想之場合，光學對比在循環之後依然不 變。循環使用能力在記錄層之層厚度達35毫微米時實際上 為不變。因此結合CET與循環使用能力之相關需求，記錄 f，厚度範圍介於1〇至35毫微米之間，較佳介於2〇至35毫 ，来之間’更佳介於2 5至3 5毫微米之間。具有記錄層厚度 ”於25至35覺微米間之媒體於第一個1 〇5 DOW循環期間具 有穩定之低跳動率。 第二介電性層之最佳厚度範圍，即介於記錄層與金屬鏡 間層，係介於1〇至5〇毫微米之間，較佳介於20至40 二1 = t間。當此層太薄時，介於記錄層與金屬鏡面層間 ,r6緣性相對受到影響。結果，記錄層之冷卻速率增 力r丄其ί致慢速之結晶過程及不良之循環使用能力。冷卻 逆·千可藉增加第二介電性層之厚度而予以降低。 白於金屬鏡面層之厚度並不敏感’若該厚度介於 . 〇笔微米之間。但若金屬鏡面層係較6 Q毫微朱薄 T循環使用能力因為冷卻速率係太慢而相對地會受影響。 若金屬鏡面層係1 6 0毫微米或更厚，循環使用能力進1^步 惡化，因而記錄與拭除電能因為熱傳導增加而必須提高^。 金屬鏡面層之厚度較佳係介於80至1 20毫微朱之間。< 第一與第二介電性層可由諸如 Sl〇2之混合物製得。其它如Si02，Ti02 , ZnS，AIN， '
第9頁 412739 五、發明說明（6) ·‘_
Si3N/ ，與Ta2 05，較佳係使用諸如Si C，WC，TaC，ZrC或. TiC之電石。此等材料提供比ZnS-Si02之混合物較快之結 晶速度與較佳之循環使用能力。 供金屬鏡面層使用者可由，諸如紹，欽，金，銀，銅， 翻，把，镇，鉻，翻，鶴與组，包_含此等金屬之合金，之 金屬製得。適當之合金實例係A1 Ti，AlCr與AlTa。 反射層和介電性層均可籍蒸氣沉積或錢锻予以提供。 資訊媒體之基材對於雷射波長至少具穿透性，且舉例而 言係由聚甲基丙烯酸甲酯（PMMA )之聚碳酸酯，非晶系聚 烯或玻璃製得。於典型實例中，基材係圓碟片狀且具有 120毫米之直徑及厚度0.6或1.2毫米。 另外，基村可為由諸如聚酯膜製得之合成樹脂撓曲性捲 帶之形式。依此方式，可獲得供諸如以快速旋轉之多邊形 為基礎之光學記錄器使用之光學記錄帶。於此類裝置中反 射之雷射光束在整個捲帶表面進行橫斷掃瞄。 在記錄層側之圓碟片狀基材之表面較佳係具備有一可予 以光學掃目苗之祠服導執（s e r v 〇 t r a c k )。此祠服導執通常 係由一螺旋狀溝槽所構成且係利用於射出模製或擠壓時成 形於基材中。此溝槽另外可由諸如丙烯酸之紫外線硬化層 之合成樹脂層之複製製程形成，其係分別施賦於基材。於 高密度記錄時，此類溝槽具有間距如0. 6〜0. 8微米及寬度 ◦. 5微采。 最外侧之疊合層可視情況而定藉諸如紫外線光硬化之聚 甲基丙烯酸酯之保護層與外在環境隔離遮蔽。
第10頁
五、發明說明（7) 问度。己錄與试除可藉使用諸如6 7 5毫微米或較短波長 (紅色至監色）之短波長雷射予以達成。一 相邕j錄層可藉合適靶材之蒸’氣沉積或濺射被塗覆於基 材上《藉沉積之層係非晶系且顯示低反射特性。為使之 構成具有高反射性之合適記錄層，此層首先必須被完全結 晶化，其即一般所參照之初期化反應（ini tial i2at ion)。 為，=的，記錄層可在加熱爐中被加熱至鍺_銻—諦合金之 結扣/度以上之温度，例如丨8 〇D合成樹脂基材，諸如 聚碳酸酯，可另外藉具充分電能之雷射光束予以加熱。此 玎於諸如記錄器之中予以確認，於此場合雷射光束掃瞄移 動中之記錄層。然後非晶系層轉局部性地加熱至該層結晶 所需要之溫度’而不致使基材被置於不利之熱負載中。 Μ 若品要’額外之薄金屬層可插入介於基封與第一介電性 層之間，因此形成所謂〇?]^-結構^雖然結構變得更複 雜，額外之金屬層增加了記錄層之冷卻速率和光學對比。 當上述材料使用於堆疊Π+ΡΙ + IM或I I + PIM中時，其中1+係 電石、氮化物或氧化物，可進一步增加.結晶速度。實驗顯 示ΙΓΡΙΜ.Μ堆疊之CET小於IPIM堆疊之70%。 本發明將藉具體範例並參考隨附之圖示極詳細地予以闡 明，其中 圖1顯示錯-録-錄以原子％計之三角形三元組合物圖之 部份。 圖2顯示按照本發明之光學資訊媒體之剖面圖示。 圖3顯示鍺（以原子％計）及銻/鎊（以原子比率計）之三元
第11頁 412739 五、發明說明（8)' 組合物圖之一部份。而 圖4顯示於组合物（GeSbcTp Ί τ。
(、t , w 、 D2ie4 ) 之合金中介於CET (n s )與χ (旲耳分率）間之關係。 實例1至4 (根據本發明） 圖2以圖顯示按照本發明之光，學眘句_ 圖。夂去斜$ ! 士 _ B=无卞貝讯碟片之部份剖面 Ξ 1衣不具有直徑12()毫米及厚度1. 2毫米之聚 扁圓形基材。基材}具備如以下結構之ιρΐΜ堆叠： —具有（ZnS)8G(Si〇2)2Q厚度為d2之第—介電性層（丨）2， 鍺-銻_諦合金之厚度為心之記錄層（p)3， 具有（ZnS )8。（S i 〇2 )2Q厚度為d4之第二介電性層（I ) 4， 具有鋁厚度為之金屬鏡面層（m)5， 諸層均由濺射所製得^記錄層3之最初結晶狀態係藉將 雷射光束聚焦於所沉積之非晶系合金予以加熱而製得。 供記錄、複製及拭除資訊之雷射光束經由基材丨進入記 錄層3内。此光束係以箭頭6圖示表之。非晶系標記係以單 一雷射脈衝能量？^ =1.25Pm(P疒開始熔融之能量）在1〇〇毫 微秒内被寫入。拭除能量為pw/2 ^ 衣1彙總根據本發明之諸實例之結果。·
1 Μ 表1 實例 d21(nrn) d3 P(nm) d., I(nm) d5 M(nrn) CET(ns) Ge(at. %) Sb(at. %) Te(at. %) 1 125 27 26 100 45 13.65 28.85 57.50 2 135 27 26 80 43 i3.75 27.40 58.85 3 125 27 26 100 49 13.55 26.10 60.35 4 115. 27 26 , 100 42 14.05 28.15 57.80
第12頁 五、 時C E T依然在5 〇毫 微秒以下，在相當於圖1與3中之頂點τ之下，若χ介於〇 〇| 與0.35之間，CET甚至依然在45毫微秒以下。^例;（χ‘ = 〇 · 1 〇 )及2 ( χ = 0 · 2 2 )係位於此遑結線上。 *60, 4 412739 發明說明（9) 實例1至4係位於圖1及圖3中之五角形區域PQRST之 内五角形之p，Q，R ’ s與τ頂點代表如申請專利圍第1項 所示組合物之合金。圖1係整個三角形三元組合物鍺_銻一 錄圖之一部份。圖示具備之頂點為篩（丨〇 〇 %錄），化合物 錯諦（5 0 %錯’ 5 Q %錆’ 0 %銻），及組合物〇 %鍺，5 〇 %錄， 50%諦。化合物GeSb2Te4 (依原子百分比為Ge“ sTe57 !) 係位於連接化合輪GeTe與Sb2Te3之連結線（虛線）β 圖3以不同格式顯示一擴大之組合物圖。垂直麵顯示鍺 含量（依at, %計），而水平軸代表銻/錄原子之比率。此 圖顯不源自圖1之連結線之一哿份及化合物GeSb2T〜。頂 占丁 ίτ、位於連接鋅與G eSbaTe4之連結線上。根據本發明之實 例1至4於五角形PQRST之區域内以交叉符號χ顯示之。 CΕ Τ之隶低值係位於連接錄與g e s b2 T e4之連結線上，且係 在五角形區域PQRST之内1諸如表1中之實例2與4所示。 圖4顯示增加錄莫耳分率χ至化合物GeS%Te4對CET之影響 上依原子百分比為GeM.3Sb28 6 TeS7」）。藉增加締，組合物沿 者連接此兩端點之連結線自G eSb2Te4向鈽偏移。若χ = 〇 〇 〇 即純化合物GeSb.Je4，CET值達53毫微秒。在添加少晉篩 Cx=0.01 )之後，CET值降至50毫微秒以下。直到 0-37 (依原子百分比為Ge132Sb264Te
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412739 '^-—____________ 五、發明說明（10) ’·. 實例I至4被應用於判斷跳動特性。跳動（J i 11 er)，係相 窗於還原數據之時序時間下介於被記錄標記與位置之邊緣 間最異之標準偏差，係應用於判斷圓碟片之循環使用能力 之標準參數。跳動必須低於時序時間τ。，即c D速度為3 〇毫 喊( 1. 2 m / s，時序時間2 3 0毫微秒）之1 2 %以下。標記 ' 之如置（1 e a d丨n g )和延置（t r a i 1 i n g)邊緣均被壹測。就本 實驗而言，圓碟片係一側具有呈溝槽形式之螺旋狀伺服導 罕九（s e r v 〇 1； r a c k ) ’並由記錄器予以初期化之基材。溝槽藉 複製製程被塗佈由紫外線硬化之丙烯酸酯層。 利同一記錄器（雷射波長6 5 0毫微米）發現線性速率高 達18 m/s ( 1 5倍於CD-速度）之隨機數據之DOW可在此等圓 碟片中成功實現。於DOW期間，新非晶系位元被寫入且同 時介於新非晶系位元間之區域係由相同之雷射光予以結晶 化。於DOW期間矸發現跳動在本質上為不變，其值約為時 序時間之8 %。此意為可達成約4 1 μ位元/秒之數據速率。 比較實例5至1 〇 (未根據本發明） 衣2彙總未根據本發明之諸實例之結果。
第14頁 丨實例d2i(nm) d； P(nm)! d41(iim) d5 M(nm) CET(ns)lGe(at. %)|Sb(at. %) Te(ai. %) 5 125 27 26 100 55 15.40 27.15 57.45 6 125 27 26 100 52 13.20 28.75 58.05 7 丨 125 27 26 100 67 11.95 26.60 61.45 8 125 27 26 100 52 14.55 25.85 59.60 9 125 27 26 100 69 14.00 25.00 61.00 10 122 27 26 「100 54 12.80 26.95 60.25 412789 五
'發明說明（ID 此等a例顯示諸C E T值高於5 0毫微秒β組合勒係位於連 接錯鎊與Sb2Tes之連結線之左側，但係在五角形PQRST之區 域外，且於圖3中係以交又符號}(顯示之。 比較實例Η至2 1 (未根據本發明） 表3彙總未根據本發明之諸實例之結果。 實例 d, I(nm) dj P(nm) d41(nm) d5 M(nm) CET(ns) Ge(at. %) Sb(at. %) Te(at. %) 11 125 27 26 100 66 14.95 28.80 56.25 12 120 27 26 100 58 13.90 29.90 56.20. 13 130 27 26 100 78 12.70 30.50 56.80 14 130 27 26 80 6f 15.50 28.05 56.45 15 133 27 26 80 52 13.10 29.75 57.15 16 125 27 26 80 57 门 4.60 28.65 56.75 17 --- 125 27 26 80 75 15.30 28.85 55.85 18 125 27 26 100 70 14,60 28.50 56.90 · _ 19 125 27 26 100 83 13.05 30.10 56.85 ..20 125 27 26 100 113 14.75 29.25 56.00 21 125 27 26 100 53 14.30 28.60 57.10 此等實例顯示諸C Ε Τ值南於5 0毫微秒。實例1 1至2 0之組 合物係位於連接鍺錄與S b2 T e3之連結線之右側，且於圖3中 係以交叉符號X顯示之。實例2 1相當於圖3中所顯示之化合 物GeSb2Te4。 根據本發明，提供了諸如供作DVD -RAM或光學記錄帶之 可重寫式相變光學資訊媒體，其具有5 0毫微秒或更少之
第15頁 412739 五、發明說明（12) CET值，係適合於直接複寫及高速記錄，且其顯示良好之 循環使用能力及在7. 2 in / s或更大之線性速率下呈微小跳 動。
412739 _案號87119m_g?年g月2夕曰__ 五 '發明說明（2) 結晶速度相對於雷射光束無法與媒體之線性速率匹配，先 前記錄之舊數據（非晶系標記）不能於DOW期間被完全移 去（再結晶）。此將引起高雜訊位準。 在公開文件中所論及之光學資訊媒體之類型可由美國專 利US 5，1 9 1，5 6 5習知。習知之相變型媒體包含依序為第一 介電性層，鍺-銻-錄相變合金記錄層，第二介電性層與金 屬反射層之圓碟形基材疊合層組成a此類疊合層可被參照 為IPIM結構，其中Μ代表反射或鏡面層，I代表介電性層而 Ρ代表相變記錄層。該專利揭示於三元組合物圖（圖5 ) 中位於計量化合物G e Sb2 T e4之脈衝時間為5 0毫微秒，在該 脈衝時間下鍺-銻-鎊組合物開始結晶。此時間不等於完全 拭除時間CET，而較短。完全拭除時間CET被定義為依統計 學量測得之於結晶環境下使被寫過之非晶系標記完全結晶 之拭除脈衝之最小時間。為完全拭除非晶系標記，必須經 成核與紋理（晶種）成長兩種製程。於該專利所論及之時 間係成核時間，即第一個晶種可被觀察到之時間。完全拭 除，即非晶系標記之完全結晶，另外耗費十或更多毫微 秒。該專利指導於三元圖中GeSb2Te4連結線之組合物更迅 速地結晶。例如計量化合物G e S b2 T e4 (原子量百分比 Gei4,3St)28.6Te57.i)即顯不具有40毫微秒之成核時間。由本案 申請人之實驗顯示此化合物具有53毫微秒之CET。 本發明之目的係特別提供了 一可重寫式光學資訊媒體， 其係適合於具有50毫微秒或更短CET值之諸如DVD-RAM與光 學記錄磁帶之高速光學記錄’。在本文中高速記錄可被解釋
O:\55\55980.ptc 第6頁 2000.08. 25.006 412739 案號 87119177 g?年浐月>·Γ曰 修正 五、發明說明（12) CET值，係適合於直接複寫及高速記錄，且其顯示良好之 循環使用能力及在7 . 2 m / s或更大之線性速率下呈微小跳 動。 元件符號說明 1 基材 2 第一介電性層 3 記錄層 4 第二介電性層 5 金屬鏡面層 6 光束
O:\55\55980.ptc 第16頁 2000. 08. 25.016

Claims (1)

  1. 41278( Μ 六、申請專利範圍 1.. 一種矛1 修c i i 光束供高速記錄之可重寫式光學實訊媒 體，該媒4¾ 十具有疊合層之基材，該疊合層依順序包 含，第一介電性層，由含有鍺，銻與#之合金所組成之相 變化材料記錄層，第二介電性層與金屬鏡面層，其特徵為 ---該合金具有之組成份係由G e - S b - T e之三元組合物 圖之區域依原子之百分比所定義，該區域係五角形且具有 以下之諸頂點： 2 :Sb25,8 Te60. 〇 (P) G e; 2.7 S b27.3 T e60. 〇 (Q) Ge η. 4 S b2g. 2 T e57. 4 (R) Ge15.1 S b27 g T e57_! (S) G e !3, 2 Sb26.4Te60.4 . (T) _ ---第一介電性層具有厚度70至（70+λ/2η)毫微米， 其中λ係雷射光束之波長，而η係此層之折射率； ---記錄層具有厚度10至35毫微米； ---第二介電性層具有厚度1 0至50毫微米； ---金屬鏡面層具有厚度60至160毫微米。 2. 如申請專利範圍第1項之光學資訊媒體，其特徵為該 合金具有如下组成份： (GeSt^TeJhTex ’其中莫耳分率X符合下式： O.OlSxSO.37,較佳為0.02^x50.35。 3. 如申請專利範圍第1項之光學資訊媒體，其特徵為該 記錄層具有厚度2 0至3 5毫微米，較佳為2 5至3 5毫微米。 4. 如申請專利範圍第1項之光學資訊媒體，其特徵為第
    第17頁 4127S9 ____£\_；_ 六'申請專利範圍 二介電性層具有厚度2 0至4 0毫微米。 5. 如申請專利範圍第丨項之光學資訊媒體1其特徵為金 屬鏡面層厚度介於80至120毫微米之間。 6. 如申請專利範圍第1項之光學資訊媒體，其特徵為金 屬鏡面層至少包含一種選擇自包括銘，鈥，金，銀，銅， 鉑，鈀，鎳，鉻，鉬，鎢與鈕，含此等金屬之合金，所組 成之金屬。 7. 如申請專利範圍第1項之光學資訊媒體，其特徵為基 材係圓碟或捲帶。 8. 如前述申請專利範圍任一項之光學資訊媒體供作高速 記錄之應用，因此介於雷射光東與媒體之相對速率至少為 7. 2 m/s °
    苐18頁 412739 _案號87119177 &月>，日 修正_ 六、申請專利範圍 1 . 一種利用雷射光束供高速記錄之可重寫式光學資訊媒 體，該媒體包含一具有疊合層之基材，該疊合層依順序包 含，第一介電性層，由含有錯，録與錄之合金所組成之相 變化材料記錄層，第二介電性層與金屬鏡面層，其特徵為 ---該合金具有之組成份係由Ge-Sb-Te之三元組合物 圖之區域依原子之百分比所定義，該區域係五角形且具有 以下之諸頂點： G e 14. 2 Sb25 .8τ e60, 0 (P) Ge 12.7 S b27 ,3τ θ60. 0 (Q) Ge 13. 4 Sb2g ,2τ e57. 4 (R) Ge 15. l Sb27, g T e57 [ (S) Ge 13. 2 Sb26 .J e60. 4 (T)； -第一 介 電性 層 具 有厚度70至 (70+ λ/2η) 毫 微米 其 中；l係雷射光束之波長 ，而n 係此層之折 射 率； —— -記錄 層 具有 厚 度 10 至35 毫微 米； —— -第二 介 電性 層 具 有厚度 1 0至 50毫微米； — -金屬 鏡 面潛 具 有 厚度6 0 至1 6 0毫微米。 2. 如申請專利範圍第1項之光學資訊媒體，其特徵為該 合金具有如下組成份： (GeSt^Te^hTej；，其中莫耳分率X符合下式： 0.0 1 ^ X ^ 0. 37 ,較佳為0. 02 S X S 0. 35。 3. 如申請專利範圍第1項之光學資訊媒體，其特徵為該 記錄層具有厚度2 0至3 5毫微米，較佳為2 5至3 5毫微米。 4. 如申請專利範圍第1項之光學資訊媒體，其特徵為第
    O:\55\55980.ptc 第1頁 2000.08.25.017 _案號 87119177_f?年兄月 >·:^曰__ 六、申請專利範圍 二介電性層具有厚度2 0至4 0毫微米。 5 .如申請專利範圍第1項之光學資訊媒體，其特徵為金 屬鏡面層厚度介於8 0至1 2 0毫微米之間。 6. 如申請專利範圍第1項之光學資訊媒體，其特徵為金 屬鏡面層至少包含一種選擇自包括鋁，鈦，金，銀，銅， 白，紀，鎳，鉻，鉬，鎢與组，含此等金屬之合金，所組 成之金屬。 7. 如申請專利範圍第1項之光學資訊媒體，其特徵為基 材係圓碟或捲帶。 8. —種如前述申請專利範圍任一項中光學資訊媒體之使 用，供作高速記錄，其中介於雷射光束與媒體之相對·速率 至少為7.2m/s。
    O:\55\55980.ptc 第2頁 2000. 08. 25.018
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