JP2000163804A - Draw type optical recording medium - Google Patents
Draw type optical recording mediumInfo
- Publication number
- JP2000163804A JP2000163804A JP10331811A JP33181198A JP2000163804A JP 2000163804 A JP2000163804 A JP 2000163804A JP 10331811 A JP10331811 A JP 10331811A JP 33181198 A JP33181198 A JP 33181198A JP 2000163804 A JP2000163804 A JP 2000163804A
- Authority
- JP
- Japan
- Prior art keywords
- layer
- recording
- recording layer
- thin film
- particle diameter
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】この発明は、光ディスク等の
光記録媒体、特にユーザが情報を書き込み消去できない
追記型の光記録媒体に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical recording medium such as an optical disk, and more particularly to a write-once optical recording medium in which a user cannot write or erase information.
【０００２】[0002]
【従来の技術】ユーザが情報を１回だけ書き込みでき消
去ができない光記録媒体として例えば追記型の光ディス
クが使用されている。この追記型の光ディスクの記録方
式としては、記録層に有機色素を用い、レーザ光の照射
により有機色素を加熱溶融して化学変化を起こしてピッ
トを形成して反射率を変化させる方式と、記録層を２層
の低融点金属薄膜で形成し、レーザ光の照射による２層
膜間の熱拡散により合金化してピットを形成する方式
と、記録層に金属合金を使用、レーザ光の照射による金
属合金の相変化により反射率を変化させる方式等が採用
されている。2. Description of the Related Art A write-once optical disc, for example, is used as an optical recording medium on which a user can write information only once and cannot erase the information. There are two types of recording methods for this write-once optical disc: an organic dye is used for the recording layer, the organic dye is heated and melted by laser light irradiation to cause a chemical change to form pits and change the reflectance. A method in which a layer is formed of two low-melting point metal thin films, and a pit is formed by alloying by thermal diffusion between the two layers by laser light irradiation, and a metal alloy is used for a recording layer, and a metal is formed by laser light irradiation A method of changing the reflectance by changing the phase of the alloy is employed.
【０００３】[0003]
【発明が解決しようする課題】しかしながら、有機色素
の溶融や２層膜間の熱拡散により合金化による記録方式
は記録するまでの安定性が不十分であり、高速度の記録
すなわち低エネルギによる記録ができなかった。また、
金属合金の相変化による記録方式は、光吸収による上昇
温度によって相変化の程度が異なるため記録媒体として
は適当でなかった。また、変化した相の安定性は充分で
はなく元へ戻るため、書き込んだ記録が消去されてしま
い記録保存の安定性が不十分であった。However, the recording system based on alloying due to melting of an organic dye or thermal diffusion between two-layer films has insufficient stability until recording, and high-speed recording, that is, recording with low energy. Could not. Also,
The recording method using the phase change of the metal alloy is not suitable as a recording medium because the degree of the phase change varies depending on the temperature rise due to light absorption. In addition, the stability of the changed phase is not sufficient and returns to the original state, so that the written record is erased and the stability of the record storage is insufficient.
【０００４】この発明はかかる問題を解消し、安定して
記録できるとともに記録した情報を安定して保持するこ
とができる追記型の光記録媒体を提供することを目的と
するものである。An object of the present invention is to solve such a problem and to provide a write-once optical recording medium capable of stably recording and stably retaining recorded information.
【０００５】[0005]
【課題を解決するための手段】この発明に係る光記録媒
体は、記録層を平均粒子径が３〜１００ｎｍの微粒子物
質からなる薄膜で形成したことを特徴とする。The optical recording medium according to the present invention is characterized in that the recording layer is formed of a thin film made of a fine particle having an average particle diameter of 3 to 100 nm.
【０００６】第２の発明に係る光記録媒体は、記録層を
平均粒子径が３〜１００ｎｍの微粒子物質からなる複数
層の薄膜で形成したことを特徴とする。An optical recording medium according to a second aspect of the invention is characterized in that the recording layer is formed of a plurality of thin films made of a fine particle substance having an average particle diameter of 3 to 100 nm.
【０００７】第３の発明に係る光記録媒体は、記録層を
連続物質の薄膜と、連続物質の薄膜の上に設けた平均粒
子径が３〜１００ｎｍの微粒子物質からなる薄膜とで形
成したことを特徴とする。According to a third aspect of the present invention, in the optical recording medium, the recording layer is formed of a thin film of a continuous material and a thin film of fine particles having an average particle diameter of 3 to 100 nm provided on the thin film of the continuous material. It is characterized by.
【０００８】上記記録層を熱拡散防止する２つの誘電体
層で狭むと良い。さらに、記録層のレーザ光の照射側と
反対側の誘電体層の表面に光の反射層を設けることが望
ましい。また、レーザ光の照射側と反対側の最上層に保
護層を設けると良い。Preferably, the recording layer is narrowed by two dielectric layers for preventing thermal diffusion. Further, it is desirable to provide a light reflection layer on the surface of the dielectric layer opposite to the laser beam irradiation side of the recording layer. Further, a protective layer is preferably provided on the uppermost layer on the side opposite to the side irradiated with the laser light.
【０００９】[0009]
【発明の実施の形態】この発明の光記録媒体は、透明基
板と第１誘電体層と記録層と第２誘電体層と反射層及び
保護層を有する。記録層は、金属や化合物の平均粒子径
が３〜１００ｎｍの微粒子を使用し、ＰＶＤ法やＣＶＤ
法により膜厚が１０〜１００ｎｍの範囲で形成されてい
る。DESCRIPTION OF THE PREFERRED EMBODIMENTS An optical recording medium according to the present invention has a transparent substrate, a first dielectric layer, a recording layer, a second dielectric layer, a reflective layer, and a protective layer. The recording layer uses fine particles having an average particle diameter of a metal or a compound of 3 to 100 nm, and is formed by a PVD method or a CVD method.
The thickness is formed in the range of 10 to 100 nm by the method.
【００１０】このように記録層を金属や化合物の平均粒
子径が３〜１００ｎｍの微粒子を使用して形成すること
により、バルク結晶で形成する場合と比較して、活性化
エネルギを低くするとともに融点を低下させ、光吸収率
も向上することができ、光記録媒体の記録感度を高める
ため必要な、記録層の光吸収率が高いこと及び熱伝導率
と熱容量が小さいこと等の要件を満たすことができる。By forming the recording layer using fine particles having an average particle diameter of a metal or a compound of 3 to 100 nm, the activation energy and the melting point can be reduced as compared with the case where the recording layer is formed of a bulk crystal. To meet the requirements, such as high light absorption of the recording layer and low thermal conductivity and heat capacity, necessary to increase the recording sensitivity of the optical recording medium. Can be.
【００１１】この記録層に書き込み用のレーザ光を照射
すると、微粒子膜を溶かして密度を大きくして連続膜に
変化して、微粒子膜中に連続膜化された記録部位が形成
される。この記録部位にレーザ光を照射しても記録部位
には大きな変化は生じなく、一度書き込んだ記録部位を
元の微粒子膜の低反射率に戻すことができず、書替え不
可能となり、書き込んだ情報を安定して保存することが
できる。When the recording layer is irradiated with a laser beam for writing, the fine particle film is melted to increase the density and change to a continuous film, so that a continuous recording portion is formed in the fine particle film. Irradiating this recording area with a laser beam does not cause a significant change in the recording area, and the written area cannot be returned to the original low reflectance of the fine particle film, making it impossible to rewrite, and the written information Can be stored stably.
【００１２】[0012]
【実施例】図１はこの発明の一実施例の構成を示す断面
図である。図に示すように、追記型の光ディスク等の光
記録媒体１は透明基板２と第１誘電体層３と記録層４と
第２誘電体層５と反射層６及び保護層７を有する。透明
基板２は、石英ガラスやサファイア，結晶化透明ガラ
ス，パイレックスガラス，Ａｌ2 Ｏ3 ，ＭｇＯ，Ｂｅ
Ｏ，ＺｒＯ2 ，Ｙ2 Ｏ3 ，ＴｈＯ2 ・ＣａＯ，ＧＧＧ
（カドリウム・ガリウム・ガーネット）などの無機材料
やＭＭＡ，ＰＭＭＡ，ポリカーボネート，ポリプロピレ
ン，アクリル系樹脂，スチレン系樹脂，ＡＢＳ樹脂，ポ
リアリレート，ポリサルフォン，ポリエーテルサルフォ
ン，エポキシ樹脂，ポリ−４−メチルペンテン−１，フ
ッ素化ポリイミド，フッ素樹脂，フェノキシ樹脂，ポリ
オレフィン系樹脂，ナイロン樹脂等の透明プラスチック
フィルムで円盤状又はテープ状に形成されている。この
透明基板２を透明プラスチックフィルムで形成すると、
軽くて曲げやすい等の利点を有する。FIG. 1 is a sectional view showing the structure of an embodiment of the present invention. As shown in the figure, an optical recording medium 1 such as a write-once optical disk has a transparent substrate 2, a first dielectric layer 3, a recording layer 4, a second dielectric layer 5, a reflective layer 6, and a protective layer 7. The transparent substrate 2 is made of quartz glass, sapphire, crystallized transparent glass, Pyrex glass, Al 2 O 3 , MgO, Be.
O, ZrO 2 , Y 2 O 3 , ThO 2 .CaO, GGG
(Cadmium, gallium, garnet) and other inorganic materials, MMA, PMMA, polycarbonate, polypropylene, acrylic resin, styrene resin, ABS resin, polyarylate, polysulfone, polyethersulfone, epoxy resin, poly-4-methylpentene -1, formed of a transparent plastic film such as a fluorinated polyimide, a fluororesin, a phenoxy resin, a polyolefin-based resin, or a nylon resin in a disk shape or a tape shape. When this transparent substrate 2 is formed of a transparent plastic film,
It has advantages such as being light and easy to bend.
【００１３】第１誘電体層３と第２誘電体層５は、透明
でかつ熱的に安定な材料、例えば金属や半金属の酸化物
や窒化物，カルコゲン化物，フッ化物，炭化物及びこれ
らの混合物等で形成されている。具体的には、ＳｉＯ
2 ，ＳｉＯ，Ａｌ2 Ｏ3 ，ＧｅＯ2 ，Ｉｎ2 Ｏ3 ，Ｔａ
2 Ｏ5 ，ＴｅＯ2 ，ＴｉＯ2 ，ＭｏＯ3 ，ＷＯ3 ，Ｚｒ
Ｏ2 ，Ｓｉ3 Ｎ4 ，ＡｌＮ，ＢＮ，ＴｉＮ，ＺｎＳ，Ｃ
ｄＳ，ＣｄＳｅ，ＺｎＳｅ，ＺｎＴｅ，ＡｇＦ，ＰｂＦ
2 ，ＭｎＦ2 ，ＮｉＦ2 ，ＳｉＣなどの単体あるいはこ
れらの混合物などを使用し、各種のＰＶＤ法やＣＶＤ法
により膜厚が５〜２００ｎｍ、好ましくは５〜３０ｎｍ
の範囲に形成されている。The first dielectric layer 3 and the second dielectric layer 5 are made of a transparent and thermally stable material, for example, oxides, nitrides, chalcogenides, fluorides, carbides and the like of metals and metalloids. It is formed of a mixture or the like. Specifically, SiO
2 , SiO, Al 2 O 3 , GeO 2 , In 2 O 3 , Ta
2 O 5 , TeO 2 , TiO 2 , MoO 3 , WO 3 , Zr
O 2 , Si 3 N 4 , AlN, BN, TiN, ZnS, C
dS, CdSe, ZnSe, ZnTe, AgF, PbF
Using a simple substance such as 2 , MnF 2 , NiF 2 , SiC or a mixture thereof, the film thickness is 5 to 200 nm, preferably 5 to 30 nm by various PVD or CVD methods.
Is formed in the range.
【００１４】記録層４は、金属や化合物の平均粒子径が
３〜１００ｎｍの微粒子を使用し、ＰＶＤ法やＣＶＤ法
により膜厚が１０〜１００ｎｍの範囲、好ましくは２０
〜６０ｎｍの範囲に形成されている。この記録層４を形
成する材料は、例えばＡ１，Ｓｂ，Ｃｏ，Ｃｒ，Ａｕ，
Ｆｅ，Ｉｎ，Ｐｂ，Ｍｇ，Ｍｎ，Ｈｇ，Ｍｏ，Ｎｉ，Ｐ
ｔ，Ｓｉ，Ｓｅ，Ａｇ，Ａｎ，Ｔｉ，Ｗ，Ｚｎ，Ｚｒや
これらの酸化物，窒化物，カルコゲン化物，フッ化物，
炭化物及びこれらの混合物が用いられる。The recording layer 4 uses fine particles of metal or compound having an average particle diameter of 3 to 100 nm, and has a thickness of 10 to 100 nm, preferably 20 to 100 nm, by PVD or CVD.
It is formed in the range of ６０60 nm. The material forming the recording layer 4 is, for example, A1, Sb, Co, Cr, Au,
Fe, In, Pb, Mg, Mn, Hg, Mo, Ni, P
t, Si, Se, Ag, An, Ti, W, Zn, Zr and their oxides, nitrides, chalcogenides, fluorides,
Carbides and mixtures thereof are used.
【００１５】反射層６は、金属や金属酸化物，金属窒素
物，金属炭化物などと金属との混合物、例えばＡｌ，Ｃ
ｕ，Ａｇ，Ａｕ，Ｐｔ，Ｒｈ，Ｚｒ，Ｃｒ，Ｔａ，Ｍ
ｏ，Ｓｉ，Ｐｄ，Ｈｆ等の金属やこれらの合金、あるい
はこれらとＺｒ酸化物，Ｓｉ酸化物，Ｓｉ窒素物，Ａｌ
酸化物等を混合したものを使用し、各種のＰＶＤ法やＣ
ＶＤ法により膜圧が１０〜３００ｎｍの範囲、好ましく
は５０〜１５０ｎｍの範囲に形成されている。反射層６
の材料としては、特にＡｌやＡｕ，Ｔａ，それらの合金
やＨｆ，Ｐｄの合金などは膜の形成が容易であり好まし
い。The reflection layer 6 is formed of a mixture of a metal, a metal oxide, a metal nitride, a metal carbide and the like, for example, Al, C
u, Ag, Au, Pt, Rh, Zr, Cr, Ta, M
metals such as o, Si, Pd, Hf and alloys thereof, or Zr oxide, Si oxide, Si nitride, Al
Using a mixture of oxides etc., various PVD methods and C
The film pressure is formed in the range of 10 to 300 nm, preferably in the range of 50 to 150 nm by the VD method. Reflective layer 6
As a material of Al, particularly, Al, Au, Ta, an alloy thereof, an alloy of Hf, Pd, and the like are preferable because the film can be easily formed.
【００１６】保護層７は、ＳｎＳ，ＳｉＯ2 ，Ｔａ2 Ｏ
5 ，ＩＴＯ，ＺｒＣ，ＴｉＣ，ＭｇＦ2 ，Ａｌ2 Ｏ3 ，
ＭｇＯ，ＢｅＯ，ＺｒＯ2 ，Ｙ2 Ｏ3 などの無機物やそ
れらの混合物又は有機樹脂により厚さが１〜３０μｍの
範囲に形成されている。有機樹脂としては、重合成モノ
マー及びオリゴマーを主成分とする光硬性樹脂組成物や
熱硬化性樹脂組成物が用いられる。The protective layer 7 is made of SnS, SiO 2 , Ta 2 O
5, ITO, ZrC, TiC, MgF 2, Al 2 O 3,
It is formed of an inorganic material such as MgO, BeO, ZrO 2 , Y 2 O 3, a mixture thereof, or an organic resin so as to have a thickness of 1 to 30 μm. As the organic resin, a photo-hardening resin composition or a thermosetting resin composition containing a polysynthetic monomer or oligomer as a main component is used.
【００１７】上記のように記録層４を金属や化合物の平
均粒子径が３〜１００ｎｍの微粒子を使用して形成する
と、バルク結晶で形成する場合と比較して、活性化エネ
ルギが低くなるとともに融点が低下して光吸収率も向上
する。この平均粒子径を１０ｎｍ以下にすると、これら
の熱特性をより向上することができる。すなわち、光記
録媒体の記録感度を高めるためには、記録層４の光吸収
率が高いこと及び記録層４の熱伝導率と熱容量が小さい
こと等が必要であり、記録層４を金属や化合物の平均粒
子径が３〜１００ｎｍの微粒子を使用して形成すること
によりこの要求を満たすことができる。As described above, when the recording layer 4 is formed using fine particles having an average particle diameter of a metal or a compound of 3 to 100 nm, the activation energy becomes lower and the melting point becomes lower than when the recording layer 4 is formed of a bulk crystal. And the light absorptance also increases. When the average particle diameter is 10 nm or less, these thermal characteristics can be further improved. That is, in order to increase the recording sensitivity of the optical recording medium, it is necessary that the light absorption of the recording layer 4 is high and the thermal conductivity and the heat capacity of the recording layer 4 are small. This requirement can be satisfied by using fine particles having an average particle diameter of 3 to 100 nm.
【００１８】このように金属や化合物の微粒子で記録層
４の膜を形成する方法には各種方式があるが、ＰＶＤ法
やＣＶＤ法のように不活性ガス中で物質を蒸発させる方
法が最も一般的に用いられる。この方法によると蒸発源
近傍のガス温度が上昇し、ガス流が生ずる。すなわち閉
じたベルジャーの中で対流が生じ、蒸発源から飛び出し
た蒸気と不活性ガスとの衝突によって急冷されて微粒子
となり、この微粒子が膜を作る。そして粒子径は不活性
ガスの圧力とガス種，ガス流速，基板温度等を変化させ
ることにより容易に制御できる。As described above, there are various methods for forming the film of the recording layer 4 with fine particles of a metal or a compound, and the most common method is to evaporate a substance in an inert gas such as a PVD method or a CVD method. It is commonly used. According to this method, the gas temperature near the evaporation source rises, and a gas flow is generated. That is, convection occurs in the closed bell jar, and is quenched by collision of the vapor jumping out of the evaporation source with the inert gas to form fine particles, and the fine particles form a film. The particle size can be easily controlled by changing the pressure and the type of the inert gas, the gas flow rate, the substrate temperature, and the like.
【００１９】一般に真空中で作製される薄膜はアモルフ
ァスであれ多結晶体であれ、原子的な連続膜であり、密
度はバルク結晶より少し小さい。しかし不活性ガス中で
作製された膜はアモルファスまたは多結晶体の微粒子か
らなり、密度は更に小さくなる。この差異は膜表面状態
に端的に表れ、微粒子からなる膜の方が表面が粗く、光
は表面で散乱するようになるので、見かけ上の反射率は
低下する。そして見た目は粒子径が大きくなるにつれて
光沢が無くなり、曇ったように見える。この反射率は物
質の種類によって当然異なるが、記録層４のレーザ光に
対する反射率は２０％程度とすることが好ましい。不活
性ガス中で作製された記録層４は真空中で作製された薄
膜に比較して反射率が低下し、レーザ光の吸収率が大き
くなる。したがって情報を書き込むときに、レーザ光の
より少ないエネルギで書き込むことができ、高速記録に
適している。また、活性化エネルギが低くなるとともに
融点が低下するから、より少ない記録エネルギで記録層
４を溶かして、密度を大きくして従来の原子的連続膜に
変化する。この情報が書き込まれた記録部位の反射率は
主として表面形状が平坦化することと膜密度が向上する
ことなどにより大幅に向上する。また、記録層４に使用
する物質によっては、書き込み用のレーザ光の照射によ
り結晶化して、さらに反射率が大きくなるので信号のＳ
／Ｎが向上する。そこで記録層４を金属や化合物の微粒
子で形成する。Generally, a thin film formed in a vacuum is an atomic continuous film, whether amorphous or polycrystalline, and has a density slightly lower than that of a bulk crystal. However, a film formed in an inert gas is composed of amorphous or polycrystalline fine particles, and the density is further reduced. This difference is apparent in the state of the film surface, and the film made of fine particles has a rougher surface, and light is scattered on the surface, so that the apparent reflectance decreases. Then, as the particle diameter increases, the luster disappears, and it looks cloudy. Although the reflectivity naturally varies depending on the type of the substance, the reflectivity of the recording layer 4 with respect to the laser beam is preferably about 20%. The recording layer 4 formed in an inert gas has a lower reflectance and a higher laser light absorption than a thin film formed in a vacuum. Therefore, when writing information, writing can be performed with less energy of the laser beam, which is suitable for high-speed recording. Further, since the activation energy is lowered and the melting point is lowered, the recording layer 4 is melted with a smaller recording energy to increase the density and change to a conventional atomic continuous film. The reflectivity of the recording portion in which this information is written is largely improved mainly by flattening the surface shape and improving the film density. Further, depending on the substance used for the recording layer 4, it is crystallized by irradiation of a writing laser beam, and the reflectance is further increased.
/ N is improved. Therefore, the recording layer 4 is formed of fine particles of a metal or a compound.
【００２０】このよう書き込み用のレーザ光を照射する
と、照射された部位の記録層４の微粒子膜を溶かして密
度を大きくして、微粒子膜中に連続膜化された記録部位
が形成される。したがって、この記録部位にレーザ光を
再度照射しても記録部位には大きな変化は生じない。な
お、書き込み時に記録層４がアモルファスのままで結晶
化しない場合は、できるだけ結晶化する高いエネルギの
レーザ光を照射して結晶化させた方が記録の安定のため
に良い。いずれにしても金属や化合物の平均粒子径が３
〜１００ｎｍの微粒子を使用した記録層４は、一度書き
込んだ記録部位を元の微粒子膜の低反射率に戻すことが
できないため書替え不可能となり、書き込んだ情報を安
定して保存することができる。When the laser light for writing is irradiated in this way, the fine particle film of the recording layer 4 at the irradiated portion is melted to increase the density, and a continuous recording portion is formed in the fine particle film. Therefore, even if the recording portion is irradiated again with the laser beam, no significant change occurs in the recording portion. If the recording layer 4 is amorphous and does not crystallize at the time of writing, it is better to crystallize by irradiating a laser beam of high energy to crystallize as much as possible for stability of recording. In any case, the average particle size of the metal or compound is 3
The recording layer 4 using fine particles of 100 nm cannot be rewritten because the recording portion once written cannot be returned to the original low reflectance of the fine particle film, and the written information can be stably stored.
【００２１】ここで記録層４は粒子径が１〜２ｎｍでも
形成することはできるが、粒子径があまり小さくなる
と、連続膜との反射率の差異が少なくなってしまう。し
たがって記録層４を形成する平均粒子径は３ｎｍ以上が
良い。また、平均粒子径が１００ｎｍ以上では書き込み
用のエネルギとして高いエネルギが必要になり、高速記
録が困難であるとともに高密度記録も困難となる。した
がって平均粒子径は１００ｎｍ以下が良い。Here, the recording layer 4 can be formed even if the particle diameter is 1 to 2 nm, but if the particle diameter is too small, the difference in the reflectance with the continuous film will be reduced. Therefore, the average particle diameter for forming the recording layer 4 is preferably 3 nm or more. On the other hand, if the average particle diameter is 100 nm or more, high energy is required as writing energy, so that high-speed recording and high-density recording are difficult. Therefore, the average particle size is preferably 100 nm or less.
【００２２】上記実施例は記録層４を１層で形成した場
合について説明したが、記録層４を２層以上の複数層の
薄膜で形成すると、さらに反射率変化の制御を容易にす
ることができる。すなわち化合物や合金化することによ
って制御できる反射率の選択範囲が広がるからである。
また複数層の薄膜からなる記録層４は、書き込み用のレ
ーザ光を照射して膜物質の構造が一度変化すると元の複
数層の状態の反射率に戻すことはできず、書替えは不可
能となる。特に１層は従来の薄膜を形成しておき、上の
層に微粒子膜を形成すると、活性化エネルギが低くなる
とともに融点が低下して光吸収率も向上するという微粒
子膜の熱特性から、従来の２層薄膜構成の場合より低エ
ネルギで書き込みを行うことができる。In the above embodiment, the case where the recording layer 4 is formed of one layer has been described. However, if the recording layer 4 is formed of a plurality of thin films of two or more layers, the control of the change in reflectance can be further facilitated. it can. That is, the selection range of the reflectivity that can be controlled by compounding or alloying is widened.
In addition, the recording layer 4 composed of a plurality of thin films cannot be returned to the original reflectivity of the plurality of layers once the structure of the film material is changed by irradiating a writing laser beam, and it is impossible to rewrite. Become. In particular, when a conventional thin film is formed for one layer and a fine particle film is formed on the upper layer, the activation energy is reduced, the melting point is reduced, and the light absorption is improved. The writing can be performed with lower energy than in the case of the two-layer thin film configuration.
【００２３】さらに記録層４を、図１に示すように、第
１の誘電体層３と第２の誘電体層５で挟むことにより、
書き込み用のレーザ光を照射したときに、レーザ光で加
熱した記録層４の熱拡散を抑えて熱感度を向上させるこ
とができ、高密度記録を行うことができる。Further, by sandwiching the recording layer 4 between the first dielectric layer 3 and the second dielectric layer 5, as shown in FIG.
When laser light for writing is irradiated, thermal diffusion of the recording layer 4 heated by the laser light can be suppressed to improve thermal sensitivity, and high-density recording can be performed.
【００２４】また、書き込み用の例えば光ビームパワー
が２０〜３０ｍＷのレーザ光は記録層４の厚さによって
は透過する場合がある。そこで第２の誘電体層５に反射
層６を設けてレーザ光を有効に利用して記録感度を向上
させる。さらに、反射層６の表面に保護層７を設けて最
表面を保護する。A laser beam for writing, for example, having a light beam power of 20 to 30 mW may be transmitted depending on the thickness of the recording layer 4. Therefore, the reflection layer 6 is provided on the second dielectric layer 5 to effectively use the laser light to improve the recording sensitivity. Further, a protective layer 7 is provided on the surface of the reflective layer 6 to protect the outermost surface.
【００２５】次ぎに上記のようにして形成した光記録媒
体１の具体例を説明する。 〔具体例１〕厚さ１ｍｍで径が５インチのポリカーボネ
ート基板からなり、グルーブ形成済みの透明樹脂基板２
上にスパッタ法により厚さが３５０ｎｍのＺｎＳ／Ｓｉ
Ｏ2＝８／２の第１の誘電体層３を形成し、形成した第
１の誘電体層３の上にガス中蒸着法によって平均粒子径
６ｎｍのＳｂ粒子で平均２５ｎｍの厚さの膜からなる記
録層４を作成した。このとき使用したガスは９９．９９
％，流量５０ｃｃｍのＡｒガスを用いた。この記録層４
の粒子径や膜厚は、膜を凍結して破断して、高分解能Ｔ
ＥＭで観察して求めた。Ｓｂ粒子はほとんどアモルファ
ス状態であった。この記録層４の表面に上記と同様にし
て第２の誘電体層５を形成し、第２の誘電体層５の上に
厚さが１２５ｎｍのＡｌからなる反射層６をスパッタ法
で形成し、反射層６の表面にスピンコート法で厚さ６μ
ｍの保護層７を形成して光ディスクからなる光記録媒体
１を作成した。この光ディスクの初期反射率をＰＵＬＳ
ＴＥＣ社製（ＤＤＶ−１０００）の評価装置を用いて測
定した結果、初期反射率は５．２％であった。この光デ
ィスクに波長６３５ｎｍで光ビームパワーが１０ｍＷの
書き込み用レーザ光を照射して書き込みした後、光ビー
ムパワーが６ｍＷのレーザ光を照射すると、記録部位の
反射率は２０．７％に向上した。その後、レーザ光の光
ビームパワーを２０ｍＷまで少しづつ変化させて記録部
位を消去しようとしたが、反射率の変化は±１％以下で
あり、書き替えることはできなかった。Next, a specific example of the optical recording medium 1 formed as described above will be described. [Specific Example 1] A transparent resin substrate 2 made of a polycarbonate substrate having a thickness of 1 mm and a diameter of 5 inches and having grooves formed thereon.
ZnS / Si with a thickness of 350 nm by sputtering
A first dielectric layer 3 of O 2 = 8/2 is formed, and a film of Sb particles having an average particle diameter of 6 nm and an average thickness of 25 nm is formed on the formed first dielectric layer 3 by a gas deposition method. Was formed. The gas used at this time was 99.99
%, And an Ar gas having a flow rate of 50 ccm was used. This recording layer 4
The particle size and film thickness of high resolution T
Observed by EM. The Sb particles were almost in an amorphous state. A second dielectric layer 5 is formed on the surface of the recording layer 4 in the same manner as described above, and a reflective layer 6 made of Al having a thickness of 125 nm is formed on the second dielectric layer 5 by sputtering. A thickness of 6 μm on the surface of the reflective layer 6 by spin coating.
The optical recording medium 1 composed of an optical disk was formed by forming the m protective layer 7. The initial reflectance of this optical disk is PULS
As a result of measurement using an evaluation device manufactured by TEC (DDV-1000), the initial reflectance was 5.2%. After irradiating the optical disk with a writing laser beam having a wavelength of 635 nm and a light beam power of 10 mW for writing, and then irradiating a laser beam having a light beam power of 6 mW, the reflectance of the recording portion was improved to 20.7%. Thereafter, an attempt was made to erase the recording portion by gradually changing the light beam power of the laser beam to 20 mW, but the change in reflectance was ± 1% or less, and the data could not be rewritten.
【００２６】〔比較例１〕上記具体例１と比較するため
に、記録層４以外は具体例１と全く同じ構成とし、記録
層４は平均粒子径６ｎｍのＳｂ粒子膜の代わりに、真空
蒸着法を用いてＳｂ薄膜を２５ｎｍの厚さで形成して光
ディスクを作製した。そして具体例１と同様に評価装置
を用いて初期反射率を測定すると９．４％であった。こ
の光ディスクに波長６３５ｎｍで光ビームパワーが１０
ｍＷの書き込み用レーザ光を照射して書き込み、光ビー
ムパワーが６ｍＷのレーザ光を照射すると、記録部位の
反射率は２１．０％であった。その後、レーザ光の光ビ
ームパワーを２０ｍＷまで少しづつ変化させて照射して
記録消去し再記録した結果、反射率が７．９％で記録さ
れ、書き替えることができた。Comparative Example 1 In order to compare with the above-mentioned specific example 1, the structure was exactly the same as that of the specific example 1 except for the recording layer 4, and the recording layer 4 was vacuum-deposited instead of the Sb particle film having an average particle diameter of 6 nm. An Sb thin film was formed to a thickness of 25 nm by using a method to manufacture an optical disk. When the initial reflectance was measured using the evaluation device in the same manner as in Example 1, it was 9.4%. This optical disc has a light beam power of 10 at a wavelength of 635 nm.
When writing was performed by irradiating a laser beam having a light beam power of 6 mW, the reflectivity of the recording portion was 21.0%. Thereafter, the light beam power of the laser beam was gradually changed to 20 mW to irradiate, and the data was recorded, erased and re-recorded. As a result, the data was recorded at a reflectivity of 7.9% and could be rewritten.
【００２７】〔具体例２〕記録層４以外は具体例１と全
く同じ構成とし、記録層４は平均粒子径６ｎｍのＳｂ粒
子膜の代わりに、平均粒子径４ｎｍのＳｂ粒子で１２ｎ
ｍの厚さの第１層膜を形成し、形成した第１層膜の上に
平均粒子径４ｎｍの粒子で１３ｎｍの厚さで第２層膜を
形成して合計厚さが２５ｎｍの積層膜とした。そして具
体例１と同じ評価装置を用いて初期反射率を測定すると
４．７％であった。この光ディスクに波長６３５ｎｍで
光ビームパワーが１０ｍＷの書き込み用レーザ光を照射
して書き込み、光ビームパワーが６ｍＷのレーザ光を照
射すると、記録部位の反射率は１９．３％に向上した。
その後、レーザ光の光ビームパワーを２０ｍＷまで少し
づつ変化させて照射して記録部位を消去して書替えよう
としたが、反射率は２１．１％であり、書き替えること
はできなかった。[Specific Example 2] Except for the recording layer 4, the structure was exactly the same as that of the specific example 1. The recording layer 4 was made of Sb particles having an average particle diameter of 4 nm instead of Sb particles having an average particle diameter of 6 nm.
A first layer film having a thickness of m is formed, and a second layer film is formed on the formed first layer film with a particle having an average particle diameter of 4 nm and a thickness of 13 nm to form a laminated film having a total thickness of 25 nm. And Then, the initial reflectance was measured using the same evaluation device as in Example 1 and found to be 4.7%. When this optical disk was irradiated with a writing laser beam having a wavelength of 635 nm and a light beam power of 10 mW for writing, and irradiated with a laser beam having a light beam power of 6 mW, the reflectance of the recording portion was improved to 19.3%.
Thereafter, the light beam power of the laser beam was changed little by little to 20 mW to irradiate the recording portion by irradiating it. However, the reflectivity was 21.1% and the rewriting was not possible.
【００２８】〔比較例２〕記録層４以外は具体例２と全
く同じ構成とし、記録層４は真空蒸着法を用いてＳｂ薄
膜を１２ｎｍの厚さで第１層膜を形成し、その上にＴｅ
薄膜の１３ｎｍの厚さの第２層膜を形成し、合計厚さが
２５ｎｍの積層膜とした。そして、評価装置を用いて初
期反射率を測定すると１０．５％であった。この光ディ
スクに波長６３５ｎｍで光ビームパワーが１０ｍＷの書
き込み用レーザ光を照射して書き込み、光ビームパワー
が６ｍＷのレーザ光を照射すると、記録部位の反射率は
反射率は２０．９％に向上した。その後、レーザ光の光
ビームパワーを２０ｍＷまで少しづつ変化させて照射し
て記録部位を消去して再記録した結果、反射率が１０．
６％で記録され、書き替えることができた。Comparative Example 2 Except for the recording layer 4, the structure was exactly the same as that of the specific example 2. The recording layer 4 was formed by forming a first layer film of a 12 nm thick Sb thin film using a vacuum evaporation method. To Te
A second layer film having a thickness of 13 nm was formed as a thin film, and a laminated film having a total thickness of 25 nm was obtained. When the initial reflectance was measured using an evaluation device, it was 10.5%. When this optical disc was irradiated with a laser beam for writing at a wavelength of 635 nm and a light beam power of 10 mW, and irradiated with a laser beam having a light beam power of 6 mW, the reflectance of the recording portion was improved to 20.9%. . Thereafter, the light beam power of the laser beam was gradually changed to 20 mW to irradiate the laser beam to erase the recorded portion and re-record the data.
It was recorded at 6% and could be rewritten.
【００２９】〔具体例３〕記録層４以外は具体例１と全
く同じ構成とし、記録層４の平均粒子径６ｎｍのＳｂ粒
子膜の代わりに真空蒸着法を用いてＳｂ薄膜を１２ｎｍ
の厚さで形成した後、平均粒子径４ｎｍのＳｂ粒子膜を
１３ｎｍの厚さで形成し、合計厚さが２５ｎｍの積層膜
とした。そして、評価装置を用いて初期反射率を測定す
ると５．２％であった。この光ディスクに波長６３５ｎ
ｍで光ビームパワーが１０ｍＷの書き込み用レーザ光を
照射して書き込み、光ビームパワーが６ｍＷのレーザ光
を照射すると、記録部位の反射率は２２．０％に向上し
た。その後、レーザ光の光ビームパワーを２０ｍＷまで
少しづつ変化させて照射して記録部位を消去して書替え
ようとしたが、反射率は２１．８％であり、書き替える
ことはできなかった。[Specific Example 3] Except for the recording layer 4, the structure was exactly the same as that of the specific example 1. Instead of the Sb particle film having an average particle diameter of 6 nm of the recording layer 4, an Sb thin film of 12 nm was formed using a vacuum evaporation method.
After that, an Sb particle film having an average particle diameter of 4 nm was formed to a thickness of 13 nm, and a laminated film having a total thickness of 25 nm was obtained. When the initial reflectance was measured using an evaluation device, it was 5.2%. This optical disc has a wavelength of 635n
When writing was performed by irradiating a writing laser beam having a light beam power of 10 mW at m and writing a laser beam having a light beam power of 6 mW, the reflectance of the recording portion was improved to 22.0%. Thereafter, the light beam power of the laser beam was gradually changed to 20 mW to irradiate the recording portion by irradiating it, and the rewriting was performed. However, the reflectivity was 21.8%, and the rewriting was not possible.
【００３０】〔比較例３〕記録層４以外は具体例３と全
く同じ構成とし、記録層４は真空蒸着法を用いてＳｂ薄
膜を１２ｎｍの厚さで形成した後、Ｓｂ薄膜を１３ｎｍ
の厚さで形成して合計２５ｎｍの積層膜とした。そし
て、評価装置を用いて初期反射率を測定すると４．４％
であった。この光ディスクに波長６３５ｎｍで光ビーム
パワーが１０ｍＷの書き込み用レーザ光を照射して書き
込み、光ビームパワーが６ｍＷのレーザ光を照射する
と、記録部位の反射率は反射率は１９．９％であった。
その後、レーザ光の光ビームパワーを２０ｍＷまで少し
づつ変化させて照射して記録部位を消去して再記録した
結果、反射率が６．３％で記録され、書き替えることが
できた。[Comparative Example 3] The recording layer 4 had the same structure as that of the specific example 3 except for the recording layer 4. The recording layer 4 was formed by forming a Sb thin film to a thickness of 12 nm using a vacuum evaporation method, and then forming an Sb thin film to a thickness of 13 nm.
To form a laminated film having a total thickness of 25 nm. When the initial reflectance is measured using the evaluation device, it is 4.4%.
Met. When writing was performed by irradiating this optical disk with a writing laser beam having a wavelength of 635 nm and a light beam power of 10 mW, and irradiating a laser beam having a light beam power of 6 mW, the reflectance of the recording portion was 19.9%. .
Thereafter, the light beam power of the laser beam was gradually changed up to 20 mW to irradiate and erase the recorded portion and re-record. As a result, the reflectivity was recorded at 6.3% and rewriting was possible.
【００３１】[0031]
【発明の効果】この発明は以上説明したように、記録層
を平均粒子径が３〜１００ｎｍの微粒子物質からなる薄
膜で形成して、活性化エネルギを低くするとともに融点
を低下させ、光吸収率も向上することができ、記録感度
を高めて高速記録をすることができる。As described above, according to the present invention, the recording layer is formed of a thin film made of a fine particle material having an average particle diameter of 3 to 100 nm. The recording sensitivity can be increased and high-speed recording can be performed.
【００３２】また、記録層に書き込み用のレーザ光を照
射すると、微粒子膜を溶かして密度を大きくして連続膜
に変化するから、一度書き込んだ記録部位を元の微粒子
膜の低反射率に戻すことがなく、書替え不可能となり、
書き込んだ情報を安定して保存することができる。When the recording layer is irradiated with a writing laser beam, the fine particle film is melted to increase the density and change to a continuous film. Therefore, the recording portion once written is returned to the original low reflectance of the fine particle film. Without rewriting,
The written information can be stored stably.
【００３３】また、記録層を平均粒子径が３〜１００ｎ
ｍの微粒子物質からなる複数層の薄膜で形成することに
より、反射率の選択範囲を広げることができ、反射率変
化の制御を容易にすることができる。The recording layer has an average particle diameter of 3 to 100 n.
By forming a thin film of a plurality of layers made of the fine particle material of m, it is possible to widen the selection range of the reflectance and to easily control the reflectance change.
【００３４】また、記録層を連続物質の薄膜と、連続物
質の薄膜の上に設けた平均粒子径が３〜１００ｎｍの微
粒子物質からなる薄膜とで形成することにより、従来の
２層薄膜構成の場合より低エネルギで書き込みを行うこ
とができる。Further, by forming the recording layer from a thin film of a continuous substance and a thin film of a fine particle substance having an average particle diameter of 3 to 100 nm provided on the thin film of the continuous substance, the conventional two-layer thin film configuration can be obtained. Writing can be performed with lower energy than in the case.
【００３５】さらに、記録層を熱拡散防止する２つの誘
電体層で狭むことにより、書き込み用のレーザ光を照射
したときに、レーザ光で加熱した記録層の熱拡散を抑え
て熱感度を向上させることができ、高密度記録を行うこ
とができる。Further, the recording layer is narrowed by two dielectric layers for preventing thermal diffusion, so that when laser light for writing is irradiated, the thermal diffusion of the recording layer heated by the laser light is suppressed, and the thermal sensitivity is reduced. And high-density recording can be performed.
【００３６】また、記録層のレーザ光の照射側と反対側
の誘電体層の表面に光の反射層を設けることにより、レ
ーザ光の熱を有効に利用して熱感度を向上させて低エネ
ルギで書き込みを行うことができる。Further, by providing a light reflecting layer on the surface of the dielectric layer opposite to the laser beam irradiation side of the recording layer, the heat sensitivity of the laser beam can be effectively utilized to improve the thermal sensitivity and reduce the energy consumption. Can be written.
【００３７】さらに、レーザ光の照射側と反対側の最上
層に保護層を設けることにより、疵などが付きにくい長
寿命の光記録媒体を安定して得ることができる。Furthermore, by providing a protective layer on the uppermost layer on the side opposite to the side irradiated with the laser beam, a long-life optical recording medium which is less likely to be scratched can be stably obtained.
【図１】この発明の実施例の構成を示す断面図である。FIG. 1 is a sectional view showing a configuration of an embodiment of the present invention.
１ 光記録媒体 ２ 透明基板 ３ 第１誘電体層 ４ 記録層 ５ 第２誘電体層 ６ 反射層 ７ 保護層 DESCRIPTION OF SYMBOLS 1 Optical recording medium 2 Transparent substrate 3 First dielectric layer 4 Recording layer 5 Second dielectric layer 6 Reflective layer 7 Protective layer
───────────────────────────────────────────────────── フロントページの続き Ｆターム(参考） 2H111 EA03 EA12 EA22 EA33 EA39 EA40 FA01 FA02 FA12 FA14 FA21 FB01 4K029 AA11 AA24 BA03 BA14 BA64 BB02 BB10 BD00 BD12 CA05 GA03 5D029 JB03 JB16 JC09 JC17 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H111 EA03 EA12 EA22 EA33 EA39 EA40 FA01 FA02 FA12 FA14 FA21 FB01 4K029 AA11 AA24 BA03 BA14 BA64 BB02 BB10 BD00 BD12 CA05 GA03 5D029 JB03 JB16 JC09 JC17
Claims (6)
微粒子物質からなる薄膜で形成したことを特徴とする追
記型の光記録媒体。1. A write-once optical recording medium, wherein the recording layer is formed of a thin film made of a fine particle substance having an average particle diameter of 3 to 100 nm.
微粒子物質からなる複数層の薄膜で形成したことを特徴
とする追記型の光記録媒体。2. A write-once type optical recording medium, wherein the recording layer is formed of a plurality of thin films made of a fine particle material having an average particle diameter of 3 to 100 nm.
薄膜の上に設けた平均粒子径が３〜１００ｎｍの微粒子
物質からなる薄膜とで形成したことを特徴とする追記型
の光記録媒体。3. A write-once type optical recording wherein a recording layer is formed of a thin film of a continuous substance and a thin film of a fine particle substance having an average particle diameter of 3 to 100 nm provided on the thin film of the continuous substance. Medium.
体層で狭んだ請求項１，２又は３記載の追記型の光記録
媒体。4. The write-once optical recording medium according to claim 1, wherein said recording layer is narrowed by two dielectric layers for preventing thermal diffusion.
の誘電体層の表面に光の反射層を設けた請求項４記載の
追記型の光記録媒体。5. The write-once type optical recording medium according to claim 4, wherein a light reflection layer is provided on the surface of the dielectric layer opposite to the laser beam irradiation side of the recording layer.
に保護層を設けた請求項１乃至５記載の追記型の光記録
媒体。6. The write-once type optical recording medium according to claim 1, wherein a protective layer is provided on an uppermost layer on a side opposite to a side irradiated with the laser beam.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10331811A JP2000163804A (en) | 1998-11-24 | 1998-11-24 | Draw type optical recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10331811A JP2000163804A (en) | 1998-11-24 | 1998-11-24 | Draw type optical recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2000163804A true JP2000163804A (en) | 2000-06-16 |
Family
ID=18247921
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10331811A Pending JP2000163804A (en) | 1998-11-24 | 1998-11-24 | Draw type optical recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2000163804A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6936403B2 (en) * | 2001-12-12 | 2005-08-30 | Fuji Photo Film Co., Ltd. | Recording medium |
| WO2006025558A1 (en) * | 2004-08-31 | 2006-03-09 | Ricoh Company, Ltd. | Write-onece-read-many optical recording medium and sputtering target thereof |
| JP2006247897A (en) * | 2005-03-08 | 2006-09-21 | Ricoh Co Ltd | Write-once type optical recording medium |
| JP2007302920A (en) * | 2006-05-09 | 2007-11-22 | Nikko Kinzoku Kk | DIELECTRIC PROTECTIVE FILM FOR ZnS-SiO2 BASED OPTICAL INFORMATION RECORDING MEDIUM AND SPUTTERING TARGET FOR FORMING THE DIELECTRIC PROTECTIVE FILM |
| KR100796228B1 (en) * | 2004-08-31 | 2008-01-21 | 가부시키가이샤 리코 | Write-once-read-many optical recording medieum |
| CN100450783C (en) * | 2004-08-31 | 2009-01-14 | 株式会社理光 | Write-onece-read-many optical recording medium and its sputtering target |
| WO2017111913A1 (en) * | 2015-12-21 | 2017-06-29 | Hewlett-Packard Development Company, L.P. | Film media kit |
| US10438627B2 (en) | 2015-02-10 | 2019-10-08 | Panasonic Intellectual Property Management Co., Ltd. | Information recording medium and method for manufacturing information recording medium |
-
1998
- 1998-11-24 JP JP10331811A patent/JP2000163804A/en active Pending
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6936403B2 (en) * | 2001-12-12 | 2005-08-30 | Fuji Photo Film Co., Ltd. | Recording medium |
| WO2006025558A1 (en) * | 2004-08-31 | 2006-03-09 | Ricoh Company, Ltd. | Write-onece-read-many optical recording medium and sputtering target thereof |
| KR100796228B1 (en) * | 2004-08-31 | 2008-01-21 | 가부시키가이샤 리코 | Write-once-read-many optical recording medieum |
| CN100450783C (en) * | 2004-08-31 | 2009-01-14 | 株式会社理光 | Write-onece-read-many optical recording medium and its sputtering target |
| JP2006247897A (en) * | 2005-03-08 | 2006-09-21 | Ricoh Co Ltd | Write-once type optical recording medium |
| JP4541192B2 (en) * | 2005-03-08 | 2010-09-08 | 株式会社リコー | Write-once optical recording medium |
| JP2007302920A (en) * | 2006-05-09 | 2007-11-22 | Nikko Kinzoku Kk | DIELECTRIC PROTECTIVE FILM FOR ZnS-SiO2 BASED OPTICAL INFORMATION RECORDING MEDIUM AND SPUTTERING TARGET FOR FORMING THE DIELECTRIC PROTECTIVE FILM |
| US10438627B2 (en) | 2015-02-10 | 2019-10-08 | Panasonic Intellectual Property Management Co., Ltd. | Information recording medium and method for manufacturing information recording medium |
| WO2017111913A1 (en) * | 2015-12-21 | 2017-06-29 | Hewlett-Packard Development Company, L.P. | Film media kit |
| US10696075B2 (en) | 2015-12-21 | 2020-06-30 | Hewlett-Packard Development Company, L.P. | Film media kit |
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