JPS62100429A - Production of optical disk substrate - Google Patents

Production of optical disk substrate

Info

Publication number
JPS62100429A
JPS62100429A JP24193085A JP24193085A JPS62100429A JP S62100429 A JPS62100429 A JP S62100429A JP 24193085 A JP24193085 A JP 24193085A JP 24193085 A JP24193085 A JP 24193085A JP S62100429 A JPS62100429 A JP S62100429A
Authority
JP
Japan
Prior art keywords
optical disk
press
disk substrate
heat
pair
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.)
Granted
Application number
JP24193085A
Other languages
Japanese (ja)
Other versions
JPH0573700B2 (en
Inventor
Hideo Torii
秀雄 鳥井
Masaki Aoki
正樹 青木
Masayuki Sakai
界　政行
Hideyuki Okinaka
秀行 沖中
Kiyoshi Kuribayashi
清 栗林
Hideto Monju
秀人 文字
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Priority to JP24193085A priority Critical patent/JPS62100429A/en
Publication of JPS62100429A publication Critical patent/JPS62100429A/en
Publication of JPH0573700B2 publication Critical patent/JPH0573700B2/ja
Granted legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B11/00—Pressing molten glass or performed glass reheated to equivalent low viscosity without blowing
    • C03B11/06—Construction of plunger or mould
    • C03B11/08—Construction of plunger or mould for making solid articles, e.g. lenses
    • C03B11/084—Construction of plunger or mould for making solid articles, e.g. lenses material composition or material properties of press dies therefor
    • C03B11/086—Construction of plunger or mould for making solid articles, e.g. lenses material composition or material properties of press dies therefor of coated dies
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B11/00—Pressing molten glass or performed glass reheated to equivalent low viscosity without blowing
    • C03B11/06—Construction of plunger or mould
    • C03B11/08—Construction of plunger or mould for making solid articles, e.g. lenses
    • C03B11/082—Construction of plunger or mould for making solid articles, e.g. lenses having profiled, patterned or microstructured surfaces
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B2215/00—Press-moulding glass
    • C03B2215/02—Press-mould materials
    • C03B2215/08—Coated press-mould dies
    • C03B2215/14—Die top coat materials, e.g. materials for the glass-contacting layers
    • C03B2215/16—Metals or alloys, e.g. Ni-P, Ni-B, amorphous metals
    • C03B2215/17—Metals or alloys, e.g. Ni-P, Ni-B, amorphous metals comprising one or more of the noble meals, i.e. Ag, Au, platinum group metals
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B2215/00—Press-moulding glass
    • C03B2215/40—Product characteristics
    • C03B2215/41—Profiled surfaces
    • C03B2215/412—Profiled surfaces fine structured, e.g. fresnel lenses, prismatic reflectors, other sharp-edged surface profiles
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B2215/00—Press-moulding glass
    • C03B2215/40—Product characteristics
    • C03B2215/44—Flat, parallel-faced disc or plate products

Abstract

PURPOSE:To easily produce the titled optical disk substrate having high-precision guide grooves by hot-pressing a massive glass material with a die having a couple of guide grooves. CONSTITUTION:A couple of dies using a heat-resistant and high-strength ceramic as the base material, provided with the coating film of a platinic noble metal alloy on the surface, and furnished with ruggedness of a guide groove shape are oppositely arranged. The couple of dies are heated and the preheated massive glass material is interposed between the dies. The material is hot-pressed by the couple of dies and then cooled to a temp. lower than the glass transition temp. of the massive glass material to produce the optical disk substrate.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は、非接触で読みとりが可能な高密度メモリメデ
ィアである光ディスク（光熱記録ディスクおよび光磁気
ディスク）に用いる光ディスク基板の製造方法に関する
ものである。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for manufacturing an optical disk substrate used for optical disks (photothermal recording disks and magneto-optical disks), which are high-density memory media that can be read without contact. .

従来の技術 光ディスクは長期保存に対する信頼性の確保が重要点の
一つであるが、それにはディスク基板として変形のない
基板を用いることが必要であり、ガラス基板を採用する
ことが望まれる。基板にガラスを用いる場合、従来から
紫外線硬化樹脂を用いたフメトボリマー法により案内溝
を設けることが一般的であった。また、最近では、これ
を更に改善した反応エツチング法により、ガラス基板に
直接凹凸の案内溝を設ける方法も開発されている（太田
賢ｄ］他、真空、　　２８（２）、７７（１９８５））
。Conventional Technology One of the important points for optical discs is to ensure reliability during long-term storage, and for this purpose, it is necessary to use a substrate that does not deform as the disc substrate, and it is desirable to use a glass substrate. When glass is used for the substrate, it has conventionally been common to provide guide grooves by the fumetoborimer method using an ultraviolet curable resin. Recently, a method has also been developed that uses a further improved reactive etching method to directly form uneven guide grooves on a glass substrate (Ken Ota et al., Vacuum, 28 (2), 77 (1985)).
.

代表的なガラス基板に案内溝を作製する工程を以下に示
す。ガラス円板を洗浄した後、ポジ形レジストをスピン
コータで２００〜３００　ｎｍの厚さに塗布し、プリベ
ークした後、アルゴンレーザ光を集光し、円板を一定速
度で回転させながら、レーザ光を円板の半径方向に移動
させる方法で、幅約０．８μｍ、ピッチ１．６μｍの螺
旋状の案内溝を記録する。次いてこの案内溝を現像して
、その後残ったレジストをマスクして、ＣＨＦ　、ガス
中で反応性イオンエッヂングを行なう。約７０ｎｍの深
さまでガラスをエツチングした後、不要になったレジス
トは酸素ガスで灰化し、除去することによって、光ディ
スク用ガラス基板に案内溝が作製されている。The steps for producing guide grooves on a typical glass substrate are shown below. After cleaning the glass disk, a positive resist is applied to a thickness of 200 to 300 nm using a spin coater, prebaked, and then an argon laser beam is focused and the laser beam is applied while rotating the disk at a constant speed. A spiral guide groove with a width of about 0.8 μm and a pitch of 1.6 μm is recorded by moving the disc in the radial direction. Next, this guide groove is developed, and then the remaining resist is masked and reactive ion etching is performed in CHF gas. After etching the glass to a depth of about 70 nm, the unnecessary resist is ashed with oxygen gas and removed, thereby creating guide grooves in the glass substrate for optical discs.

発明が解決しようとする問題点 このようなプロセスでは、レジスト上の案内溝パターン
の現像工程や反応性イオンエソチング工程などに高い精
度が要求され、かつ、工程が長い欠点があった。Problems to be Solved by the Invention In such a process, high precision is required in the development process of the guide groove pattern on the resist, the reactive ion etching process, etc., and the process is long.

本発明は、このような欠点を克服すべくなされたもので
あり、極めて少ない工程で容易に光ディスク用ガラス基
板の案内溝を作製する方法を提供することを目的として
いる。The present invention has been made to overcome these drawbacks, and an object of the present invention is to provide a method for easily producing a guide groove for a glass substrate for an optical disc with extremely few steps.

問題点を解決するための手段 本発明は上記問題点を解決するために、案内溝形状の凹
凸を設けた耐熱性材料の一対の押し型を加熱し、これら
の一対の間にあらかじめ加熱したガラス材料塊状物をは
さみ、上記の一対の押し型でプレスし、そのまま、ガラ
ス材料塊状物のガラス転移温度よりも低い温度まで冷却
する方法でもって、光ディスク用ガラス基板の案内溝を
作製するものである。Means for Solving the Problems In order to solve the above-mentioned problems, the present invention heats a pair of pressing molds of a heat-resistant material provided with guide groove-shaped unevenness, and inserts preheated glass between the pair. A guide groove for a glass substrate for an optical disk is produced by sandwiching a material lump, pressing it with the above pair of press dies, and cooling it as it is to a temperature lower than the glass transition temperature of the glass material lump. .

作用 本発明は、ガラス材料塊状物をあたかもレコードディス
クのプレス成形のように、一対の案内溝パターンをもつ
押し型で加熱プレス成形して案内溝を形成する方法であ
るので、製造工程が少なくなると同時に高精度で案内溝
のパターンを形成された押し型を用うれば、容易に高精
度の案内溝が形成できるという作用がなされる。Function The present invention is a method of forming guide grooves by hot press molding a glass material block using a press die having a pair of guide groove patterns, just as in the press molding of a record disc, so that the number of manufacturing steps is reduced. At the same time, by using a press die in which a pattern of guide grooves is formed with high precision, the effect that guide grooves with high precision can be easily formed is achieved.

実施例 以下、本発明の一実施例の光ディスク基板の製造方法に
ついて、説明する。EXAMPLE A method for manufacturing an optical disc substrate according to an example of the present invention will be described below.

直径１７０　ｍｌで高さ６０ｍ１１のタングステンカー
バイド（ＷＣ）（組成；　Ｗ　Ｃ／　Ｃｏ　／　Ｃｒ　
ａ　Ｃ２−９１／８／１　　（ｗｔ％））の稠密な焼結
体の円柱を準備し、一方の底面を鏡面研磨した後、高周
波スパッタ装置を用いて厚み３μｍの白金−イリジウム
合金膜を形成した。合金膜形成後、スパッタ膜表面を鏡
面加工した。このようにして作製した鏡面加工面をもつ
白金−イリジウム合金コーティングタングステンカーバ
イド焼結体ブロックを２ケ準備した。その一方のブロッ
クの鏡面加工表面上に幅０．８μｍピンチ１．６μｍの
螺旋状で高さ０．１μｍに精密加工した凸形状部分を設
けた。このようにして螺旋状の凸形状パターンをもつ白
金−イリジウム合金コーティングタングステンカーバイ
ド焼結体ブロックと、鏡面加工面をもつ白金−イリジウ
ム合金コーティングタングステンカーバイド焼結体ブロ
ックの２個からなる一対の押し型１，２を作製した。Tungsten carbide (WC) (composition; WC/Co/Cr) with a diameter of 170 ml and a height of 60 m11
a A cylinder of a dense sintered body of C2-91/8/1 (wt%) was prepared, one bottom surface was mirror-polished, and a platinum-iridium alloy film with a thickness of 3 μm was formed using a high-frequency sputtering device. did. After forming the alloy film, the surface of the sputtered film was mirror-finished. Two platinum-iridium alloy coated tungsten carbide sintered blocks having mirror-finished surfaces prepared in this way were prepared. On the mirror-finished surface of one of the blocks, a convex shaped part was provided on the mirror-finished surface of one of the blocks in a spiral shape with a width of 0.8 μm and a pinch of 1.6 μm and a precision-machined convex portion with a height of 0.1 μm. In this way, a pair of press molds consisting of a platinum-iridium alloy coated tungsten carbide sintered body block with a spiral convex pattern and a platinum-iridium alloy coated tungsten carbide sintered body block with a mirror-finished surface are formed. 1 and 2 were produced.

この一対の型１，２を、図に示すプレスマシンにセント
して、あらかじめ、６００°Ｃに加熱した組成がＳｉＯ
□６８ｗｔ％、Ｋ　２０８　ｗ　ｔ％。The pair of molds 1 and 2 are placed in the press machine shown in the figure, and the composition heated to 600°C is SiO2.
□68 wt%, K 208 wt%.

Ｂ２Ｏ３１１ｗｔ％、Ｂａ０２ｗｔ％、ＮａＮａ２Ｏ１
Ｑ％の光学ガラスの塊状物（直径］、５０．Ｏｎ、厚み
４．３Ｒの円板形状）３を７００℃に加熱した一対の型
の間に設置し、圧力２ｋｇ−（至）′２で上下に位置し
た一対の型のすきまが４．０ｍｍになるようにして２分
間保持したのち、円板形状ガラス材を型にはさんだまま
４５０℃まで１０分間で冷却して、成形後のガラス円板
をとり出した。B2O3 11wt%, Ba02wt%, NaNa2O1
A lump of optical glass (diameter: 50.On, disk shape, thickness 4.3R) 3 of Q% was placed between a pair of molds heated to 700°C, and heated at a pressure of 2kg-(to)'2. After holding the pair of molds placed above and below with a gap of 4.0 mm for 2 minutes, the disk-shaped glass material was cooled to 450°C for 10 minutes while being sandwiched between the molds to form a glass circle after molding. I took out the board.

得られたガラス円板はプレス型の中心にあらかじめ用け
た凸部によってドーナツ形状に成形されていた。この中
心の凸部を基準に直径１５０．０ｍｍ＋になるように成
形後のガラス円板の側面を切断加工して、案内溝をもつ
光ディスクの円板形状のガラス基板を作製した。The obtained glass disk was formed into a donut shape by a convex portion previously provided at the center of the press mold. The side surface of the formed glass disk was cut to have a diameter of 150.0 mm+ based on the central convex portion, thereby producing a disk-shaped glass substrate for an optical disk having guide grooves.

得られたガラス基板の表面の案内溝がプｌ／ス型そのま
ま転写されて、精度高く形成され″こいるかどうかを成
形後のガラス円板表面を走査型電子顕微鏡を用いて評価
した。その結果、」−述のプレス条件で成形して作製し
たガラス円板は、正確に幅０．８０±０．０２１ｆｍ、
ピンチ１．６０±０．０２μｍで高さ０．１０：”：０
．０２μｍの開部分として案内溝が形成されていること
がわかった。The surface of the glass disk after molding was evaluated using a scanning electron microscope to determine whether the guide grooves on the surface of the obtained glass substrate could be directly transferred to the press mold and formed with high precision.The results were as follows. The glass disk formed by forming under the above press conditions had a width of exactly 0.80±0.021 fm,
Pinch 1.60±0.02μm and height 0.10:”:0
．． It was found that the guide groove was formed as an opening of 0.2 μm.

ただし、この案内溝の形状が適切なものかどうかは不明
であるが、本プレス方法を用い、本プレス条件を用うれ
ば、押し型を正確に転写したガラス円板が作製できるの
で、光ディスクの案内溝として最適のパターンをもつプ
レス押し型を使えば、容易に良好な案内溝をもつ光ディ
スク用ガラス基板が製造できることがわかる。However, it is unclear whether the shape of this guide groove is appropriate, but if this pressing method and pressing conditions are used, a glass disk with an accurate transfer of the stamping die can be manufactured, so it is possible to It can be seen that a glass substrate for optical disks with good guide grooves can be easily manufactured by using a press die with an optimal pattern for the guide grooves.

なお、押し型の母材として、上述の実施例のかわりにタ
ングステンカーバイド焼結体のかわりに、高密度のチタ
ンカーバイド焼結体（組成；ＴｉＣ／Ｎ　ｉ／Ｔａ　Ｃ
＋Ｃｒａ　Ｃ，、＝　８３／　１５／　２ｗｔ％）を用
いた場合も同様の結果を得ることができた。In addition, instead of the tungsten carbide sintered body in the above embodiment, a high-density titanium carbide sintered body (composition: TiC/N i/Ta C
Similar results could be obtained when using +Cra C, = 83/15/2wt%).

また、型表面に設ける白金系合金膜として、別の組成の
白金−イリジウム合金や白金−ロジウム合金、白金−オ
スミウム合金などを用いた場合も押し型の作製のための
加工性がやや異なるが、同様の方法で同様のガラス基板
が得られた。以トの実施例の結果を表１にまとめて示す
。In addition, when a platinum-iridium alloy, platinum-rhodium alloy, platinum-osmium alloy, etc. with a different composition is used as the platinum-based alloy film provided on the mold surface, the processability for making the press mold will be slightly different. A similar glass substrate was obtained in a similar manner. The results of the following examples are summarized in Table 1.

（以　下　余　白） ｌｌ 発明の効果 以−にに述べてきたように、本発明によれば、極めて容
易に高精度な案内溝をもった光ディスク用ガラス基板の
製造が可能になり、かつ、製造工程数も少なくすむので
、光ディスク用ガラス基板の低コスト化が可能となる。(Margins below) 1. Effects of the Invention As described above, according to the present invention, it is possible to extremely easily manufacture a glass substrate for an optical disk having highly accurate guide grooves, and Since the number of manufacturing steps can be reduced, it is possible to reduce the cost of the glass substrate for optical discs.

【図面の簡単な説明】[Brief explanation of drawings]

図は本発明の一実施例で用いたプレスマシンの概略図で
ある。 １．２・・・・・・押し型、３・・・・・・原料光学ガ
ラス円板、４．５・・・・・・押し型加熱ヒータ、６・
・・・・・原料ガラス円板供給治具、７・・・・・・上
型用ビスｌ−フシリンダ−，８・・・・・・下型用ピス
トンシリンダー、９・・・・・・原料ガラス円板予備加
熱トンネル炉、１０・・・・・・成形ディスクとり出し
［」。The figure is a schematic diagram of a press machine used in an embodiment of the present invention. 1.2...Press mold, 3...Raw material optical glass disk, 4.5...Press mold heater, 6.
... Raw material glass disk supply jig, 7 ... Screw cylinder for upper mold, 8 ... Piston cylinder for lower mold, 9 ... Raw material Glass disk preheating tunnel furnace, 10... Taking out the molded disk [''.

Claims (4)

【特許請求の範囲】[Claims] （１）案内溝形状の凹凸を設けた耐熱性材料の一対の押
し型を加熱し、これらの一対の間にあらかじめ加熱した
ガラス材料塊状物をはさみ、上記一対の押し型でプレス
し、そのまま、上記ガラス材料塊状物のガラス転移温度
より低い温度まで冷却する光ディスク基板の製造方法。(1) Heat a pair of press molds of a heat-resistant material provided with unevenness in the shape of guide grooves, sandwich a pre-heated glass material block between the pair, press with the pair of press molds, and as it is, A method for manufacturing an optical disk substrate, comprising cooling the glass material lump to a temperature lower than the glass transition temperature. （２）一対の押し型の構造が、耐熱性高強度セラミック
スを母材としガラス材料塊状物と接する表面に白金系貴
金属合金のコーティング膜を設けた構造であることを特
徴とする特許請求の範囲第１項記載の光ディスク基板の
製造方法。(2) Claims characterized in that the structure of the pair of press dies is such that the base material is heat-resistant high-strength ceramics and a coating film of a platinum-based precious metal alloy is provided on the surface that comes into contact with the glass material block. 2. The method for manufacturing an optical disc substrate according to item 1. （３）押し型の母材の耐熱性高強度セラミックスが、タ
ングステンカーバイド焼結体であることを特徴とする特
許請求の範囲第１項記載の光ディスク基板の製造方法。(3) The method for manufacturing an optical disk substrate according to claim 1, wherein the heat-resistant, high-strength ceramic of the base material of the press mold is a tungsten carbide sintered body. （４）押し型の母材の耐熱性高強度セラミックスが、チ
タンカーバイド焼結体であることを特徴とする特許請求
の範囲第１項記載の光ディスク基板の製造方法。(4) The method for manufacturing an optical disk substrate according to claim 1, wherein the heat-resistant, high-strength ceramic of the base material of the press mold is a titanium carbide sintered body.
JP24193085A 1985-10-29 1985-10-29 Production of optical disk substrate Granted JPS62100429A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP24193085A JPS62100429A (en) 1985-10-29 1985-10-29 Production of optical disk substrate

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP24193085A JPS62100429A (en) 1985-10-29 1985-10-29 Production of optical disk substrate

Publications (2)

Publication Number Publication Date
JPS62100429A true JPS62100429A (en) 1987-05-09
JPH0573700B2 JPH0573700B2 (en) 1993-10-14

Family

ID=17081680

Family Applications (1)

Application Number Title Priority Date Filing Date
JP24193085A Granted JPS62100429A (en) 1985-10-29 1985-10-29 Production of optical disk substrate

Country Status (1)

Country Link
JP (1) JPS62100429A (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62203101A (en) * 1986-03-04 1987-09-07 Canon Inc Manufacture of optical element with fine pattern on surface and die used therefor
JPS6426807A (en) * 1987-07-23 1989-01-30 Canon Kk Production of light guide
JPH0251434A (en) * 1988-08-15 1990-02-21 Hoya Corp Mold for press-molding glass
US5013348A (en) * 1988-07-13 1991-05-07 Hoya Corporation Mold assembly and methods for producing molded glass
JPH0444640A (en) * 1990-06-11 1992-02-14 Matsushita Electric Ind Co Ltd Stationary magnetic disk and production thereof
US5427599A (en) * 1987-06-09 1995-06-27 International Business Machines Corporation System for stamping an optical storage disk
JP2005025822A (en) * 2003-06-30 2005-01-27 Sony Corp Recording medium substrate, recording medium, and these manufacturing methods and formation device of recording medium substrate

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60176930A (en) * 1984-02-21 1985-09-11 Matsushita Electric Ind Co Ltd Mold for press molding glass lens

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60176930A (en) * 1984-02-21 1985-09-11 Matsushita Electric Ind Co Ltd Mold for press molding glass lens

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62203101A (en) * 1986-03-04 1987-09-07 Canon Inc Manufacture of optical element with fine pattern on surface and die used therefor
US5427599A (en) * 1987-06-09 1995-06-27 International Business Machines Corporation System for stamping an optical storage disk
JPS6426807A (en) * 1987-07-23 1989-01-30 Canon Kk Production of light guide
US5013348A (en) * 1988-07-13 1991-05-07 Hoya Corporation Mold assembly and methods for producing molded glass
JPH0251434A (en) * 1988-08-15 1990-02-21 Hoya Corp Mold for press-molding glass
JPH0444640A (en) * 1990-06-11 1992-02-14 Matsushita Electric Ind Co Ltd Stationary magnetic disk and production thereof
JP2005025822A (en) * 2003-06-30 2005-01-27 Sony Corp Recording medium substrate, recording medium, and these manufacturing methods and formation device of recording medium substrate

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