JPH01145342A - Production of optical element - Google Patents
Production of optical elementInfo
- Publication number
- JPH01145342A JPH01145342A JP30221987A JP30221987A JPH01145342A JP H01145342 A JPH01145342 A JP H01145342A JP 30221987 A JP30221987 A JP 30221987A JP 30221987 A JP30221987 A JP 30221987A JP H01145342 A JPH01145342 A JP H01145342A
- Authority
- JP
- Japan
- Prior art keywords
- film
- optical element
- heat
- resist
- mold
- 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
Links
- 230000003287 optical effect Effects 0.000 title claims abstract description 18
- 238000004519 manufacturing process Methods 0.000 title claims description 10
- 239000000463 material Substances 0.000 claims abstract description 39
- 229910052751 metal Inorganic materials 0.000 claims abstract description 10
- 239000002184 metal Substances 0.000 claims abstract description 10
- 239000002253 acid Substances 0.000 claims abstract description 8
- 239000012670 alkaline solution Substances 0.000 claims abstract description 7
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 7
- 239000000956 alloy Substances 0.000 claims abstract description 7
- 238000005530 etching Methods 0.000 claims abstract description 5
- 238000001312 dry etching Methods 0.000 claims abstract description 4
- 150000004767 nitrides Chemical class 0.000 claims abstract description 3
- 230000009257 reactivity Effects 0.000 claims abstract description 3
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical group [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims abstract 4
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims abstract 2
- 229910052718 tin Inorganic materials 0.000 claims abstract 2
- 238000000465 moulding Methods 0.000 claims description 10
- 238000000034 method Methods 0.000 claims description 9
- 239000011195 cermet Substances 0.000 claims description 7
- 239000010949 copper Substances 0.000 claims description 6
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical group [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 5
- 229910052802 copper Inorganic materials 0.000 claims description 5
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 4
- -1 composed of TiC Chemical compound 0.000 claims description 3
- 229910052782 aluminium Inorganic materials 0.000 claims description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 2
- 229910052759 nickel Inorganic materials 0.000 claims description 2
- 239000011248 coating agent Substances 0.000 abstract description 4
- 238000000576 coating method Methods 0.000 abstract description 4
- 239000005357 flat glass Substances 0.000 abstract description 2
- 238000003825 pressing Methods 0.000 abstract description 2
- 229910034327 TiC Inorganic materials 0.000 abstract 1
- 239000003513 alkali Substances 0.000 abstract 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 abstract 1
- 238000010276 construction Methods 0.000 abstract 1
- 229910052593 corundum Inorganic materials 0.000 abstract 1
- 239000011159 matrix material Substances 0.000 abstract 1
- 239000003870 refractory metal Substances 0.000 abstract 1
- 229910003470 tongbaite Inorganic materials 0.000 abstract 1
- 229910001845 yogo sapphire Inorganic materials 0.000 abstract 1
- 229910018967 Pt—Rh Inorganic materials 0.000 description 4
- 229910003460 diamond Inorganic materials 0.000 description 3
- 239000010432 diamond Substances 0.000 description 3
- 238000001755 magnetron sputter deposition Methods 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- 230000003746 surface roughness Effects 0.000 description 2
- 229910000629 Rh alloy Inorganic materials 0.000 description 1
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 239000012778 molding material Substances 0.000 description 1
- 238000000206 photolithography Methods 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 229920001296 polysiloxane Polymers 0.000 description 1
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 1
- 229910010271 silicon carbide Inorganic materials 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
- UONOETXJSWQNOL-UHFFFAOYSA-N tungsten carbide Chemical compound [W+]#[C-] UONOETXJSWQNOL-UHFFFAOYSA-N 0.000 description 1
Landscapes
- ing And Chemical Polishing (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は高精度な形状を有する光学素子を安価に製造す
るための光学素子の製造方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an optical element manufacturing method for manufacturing an optical element having a highly accurate shape at low cost.
従来の技術
近年、光学素子は光学機器の高性能化、軽量化に伴い、
著しく高精度の素子が要求されてきている。例えばレン
ズでは非球面レンズをプレス成形により製造しようと試
られている。このため型材料としてシリコンカーバイド
またはシリコンナイトライドを用いたプレス成形用型（
例えば特開昭５２−４５６１３号公報）や、タングステ
ンカーバイドあるいはサーメットを母材とし前記母材上
に被プレス材料と反応しない耐熱性膜をコーティングし
たプレス成形用型（例えば特願昭５９−９９０５９号）
などが提案されている。しかし前述した型材料を高精度
に加工する事をダイヤモンドバイトの摩耗が原因となり
非常にむずかしく、プレス成形型のコストアップの要因
となっていた。これらの問題を解決するために、シリコ
ンを母材とした成形型（例えば特願昭６０−１５５４０
５号）やＷＣ又はサーメット上にダイヤモンドバイトで
の加工性に特に優れた中間層をもうけ、この中間層を高
精度に加工した後、被プレス材料と反応しない耐熱性膜
をコーティングしたプレス成形用型（例えば特願昭６０
−１４０８２４号）で光学素子をプレス成形する方法が
提案されている。Conventional technology In recent years, optical elements have become more sophisticated as optical equipment becomes more sophisticated and lighter.
There is a growing demand for devices with extremely high precision. For example, attempts have been made to manufacture aspherical lenses by press molding. For this reason, press molding molds using silicon carbide or silicon nitride as the mold material (
For example, Japanese Patent Application Laid-Open No. 52-45613), press molding molds having a base material of tungsten carbide or cermet and coating the base material with a heat-resistant film that does not react with the material to be pressed (for example, Japanese Patent Application No. 59-99059) )
etc. have been proposed. However, it is extremely difficult to process the above-mentioned mold material with high precision due to wear of the diamond cutting tool, which is a factor in increasing the cost of press molding molds. In order to solve these problems, molds made of silicone as a base material (for example,
For press forming, an intermediate layer is formed on No. 5), WC, or cermet that is particularly easy to work with a diamond tool, and after this intermediate layer is processed with high precision, it is coated with a heat-resistant film that does not react with the material to be pressed. Mold (for example, patent application 1986)
140824) proposes a method of press-molding an optical element.
発明が解決しようとする問題点
このようなシリコンを母材とした型材料では型のチッピ
ングが発生しやすいという欠点と、母材と耐熱性膜との
接着強度が得られにくいという欠点を有し、型の寿命と
しては不十分であった。また、ＷＣ又はサーメット上に
ダイヤモンドバイトでの加工性に特に優れた中間層をも
うけ、この中間層を高精度に加工した後、耐熱性膜をコ
ーティングして作製した成形型の場合も、中間層が比較
的やわらかいという欠点と中間層として成形した金属が
低融点のため成形温度で粒成長を起しプレス面の表面粗
度をくずしやすいという欠点があった。このため上記構
成の成形型を用いて高精度な光学素子を安定、かつ安価
に製造できないという問題点があった。Problems to be Solved by the Invention Molding materials using silicon as a base material have the drawbacks that chipping of the mold is likely to occur and that it is difficult to obtain adhesive strength between the base material and the heat-resistant film. , the life of the mold was insufficient. In addition, in the case of a mold made by forming an intermediate layer that is particularly easy to work with a diamond tool on WC or cermet, and after processing this intermediate layer with high precision, coating it with a heat-resistant film, the intermediate layer The disadvantages are that the intermediate layer is relatively soft, and the metal formed as the intermediate layer has a low melting point, causing grain growth at the forming temperature, which tends to destroy the surface roughness of the pressed surface. For this reason, there was a problem in that a high-precision optical element could not be manufactured stably and inexpensively using the mold having the above-mentioned configuration.
問題点を解決するための手段
本発明は上記の問題点を解決するため耐熱性および高温
での強度に優れた材料を母材とし、この母材を所望の形
状に近い形状まで加工した後、被プレス材料との反応性
に乏しく、高温強度に優れた耐熱性の膜を母材上に被覆
し、前記耐熱性膜上に酸又はアルカリ溶液で簡単にエツ
チングされうる材料を所望の厚さに成膜した後、前記材
料により成る膜上にレジストを用いて所望のパターンを
形成し、酸又はアルカリ溶液を用い材料より成る膜の一
部をエツチングすることによりパターンの凹凸を強調す
る工程を経た後、乾式エツチングによりレジスト及び材
料より成る膜を完全に除去し、耐熱性膜を所望の形状に
エツチング加工して光学素子成形用金型を作製した。こ
のように酸またはアルカリ溶液による材料より成る膜の
エツチングを行なうことにより、レジストと耐熱性膜と
の乾式エツチングレートの顕しい差を微妙にコントロー
ルできるのである０以上のようにして作成したプレス成
形用金型を用いることにより高精度な光学素子をプレス
成形により安定かつ安価に提供しようとしたものである
。Means for Solving the Problems In order to solve the above problems, the present invention uses a material with excellent heat resistance and strength at high temperatures as a base material, and after processing this base material into a shape close to the desired shape, A heat-resistant film with poor reactivity with the material to be pressed and excellent high-temperature strength is coated on the base material, and a material that can be easily etched with an acid or alkaline solution is coated on the heat-resistant film to the desired thickness. After the film is formed, a desired pattern is formed using a resist on the film made of the material, and a part of the film made of the material is etched using an acid or alkaline solution to emphasize the unevenness of the pattern. Thereafter, the film made of the resist and material was completely removed by dry etching, and the heat-resistant film was etched into a desired shape to produce a mold for molding an optical element. By etching the film made of the material with an acid or alkaline solution, it is possible to delicately control the noticeable difference in dry etching rate between the resist and the heat-resistant film. This is an attempt to stably and inexpensively provide a highly accurate optical element by press molding using a mold.
作用
本発明では、耐熱性に優れた高強度母材を所望の形状に
近い形状に加工し、この上に高強度耐熱性膜をコーティ
ングした後、この耐熱性コーテイング膜を高精度にエツ
チング加工して高精度なプレス面を有する成形型を作製
したものであり、比較的軟かな金属を中間層として設け
たり、もろくてかけやすいシリコンを母材として用いた
りする必要なく高精度なプレス面を得ることを可能とし
たものである。上記のように作製した成形金型を用いる
ことにより高精度な光学素子を安定かつ安価に製造する
ことができるようにしたものである。Function In the present invention, a high-strength base material with excellent heat resistance is processed into a shape close to the desired shape, a high-strength heat-resistant film is coated thereon, and then this heat-resistant coating film is etched with high precision. A mold with a high-precision press surface was created using the same method, and a high-precision press surface was obtained without the need to provide a relatively soft metal as an intermediate layer or use brittle and easy-to-slip silicon as a base material. This made it possible. By using the molding die produced as described above, a highly accurate optical element can be manufactured stably and at low cost.
実施例
以下、本発明の一実施例について、図面を用いて説明す
る。まず、たて５ｃ１１、厚さ２ｃＩＩＩのＷＣ母材１
０を鏡面研摩してその表面粗度をＲＭＳ＝ ８〜１０人
に仕上げた後第１図（ａ）に示すように耐熱性膜ｐｔ−
Ｒｈ合金１１をマグネトロンスパッタ装置を用いて成膜
した。続いて銅膜１２をＰｔ−Ｒｈ合金１１上にマグネ
トロンスパッタ装置を用いて成膜したものが第１図（ｂ
）である。その後、銅膜１２上にレジスト１３を塗布し
、フォトリソグラフィにより所望する最終形状が得られ
るようパターンを形成したものが第１図（Ｃ）である。EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings. First, WC base material 1 with a length of 5c11 and a thickness of 2cIII
After polishing the surface to a surface roughness of RMS = 8 to 10, a heat-resistant film pt-
Rh alloy 11 was formed into a film using a magnetron sputtering device. Next, a copper film 12 was formed on the Pt-Rh alloy 11 using a magnetron sputtering device, as shown in Fig. 1(b).
). Thereafter, a resist 13 is applied onto the copper film 12, and a pattern is formed by photolithography to obtain a desired final shape, as shown in FIG. 1(C).
この後、銅膜１２の一部をエツチングにより除去し、所
望するパターンの凹凸を強調したものが第１図（ｄ）で
ある。最後に、レジスト１３及び銅膜１２の全てと耐熱
性膜ｐｔ−Ｒｈｉｉの一部をエツチングにより除去して
最終の所望する形状の金型に作製したのが第１図（ｅ）
である。以上のようにして作成した成形型を用いて平板
ガラスをプレスすることにより０．８μｍピッチで、深
さ０．８μｍの回折格子を安定に製造することができた
。なお本発明の実施例では、母材にＷＣを主成分とする
超硬合金、耐熱性膜にＰｔ−Ｒｈ合金を選んだが、母材
としては他にサーメットも使用可能で有り、耐熱性膜と
しても他に白金族金属を主成分とする合金、ちっ化物、
炭化物、あるいはホウ化物なども使用可能である。また
、プレス面パターンの凹凸を強調するために用いられる
酸またはアルカリ溶液に簡単にエツチングされる金属膜
としてはニッケル及びアルミニウムなども使用可能であ
る。Thereafter, a portion of the copper film 12 is removed by etching to emphasize the desired pattern irregularities, as shown in FIG. 1(d). Finally, all of the resist 13 and copper film 12 and a part of the heat-resistant film pt-Rhii were removed by etching to produce a mold with the final desired shape as shown in FIG. 1(e).
It is. By pressing flat glass using the mold created as described above, it was possible to stably produce a diffraction grating with a pitch of 0.8 μm and a depth of 0.8 μm. In the examples of the present invention, a cemented carbide whose main component is WC and a Pt-Rh alloy were selected as the base material and a Pt-Rh alloy as the heat-resistant film, but cermets can also be used as the base material. In addition, alloys whose main components are platinum group metals, nitrides,
Carbides or borides can also be used. Further, nickel, aluminum, etc. can also be used as the metal film that is easily etched in an acid or alkaline solution used to emphasize the unevenness of the pressed surface pattern.
発明の効果
以上述べたように、本発明は多少加工性に劣るような母
材でも、はぼ所望の形状に近い形状にさえ加工できれば
、前記母材上に形成した耐熱性膜の一部とレジスト及び
湿式エツチングしやすい金属膜の全てを完全にエツチン
グ除去して加工することにより高精度なプレス面をもつ
成形型に簡単に作製することができるようにしたもので
、これにより従来加工性を考慮するため母材選択の自由
度があまりないという欠点を解決し、さらに高精度加工
のために比較的やわらかな金属を中間層として設けるた
めに型の寿命が十分でないというような欠点をも解決し
たものであり、本発明により高精度な光学素子を安定に
プレス成形することを可能としたものである。Effects of the Invention As described above, the present invention allows even a base material with somewhat inferior workability to be processed into a shape close to the desired shape, as a part of the heat-resistant film formed on the base material. By completely removing all resist and metal films that are easy to wet-etch, it is possible to easily create a mold with a highly precise press surface, which improves the processability of conventional methods. This solves the drawback that there is not much freedom in selecting the base material, and also solves the drawback that the life of the mold is not sufficient because a relatively soft metal is used as an intermediate layer for high-precision machining. The present invention has made it possible to stably press mold a highly accurate optical element.
第１図は本発明で構成した成形用金型作製の工程図であ
る。
１０・・・・・・母材ＷＣ１１１・・・・・・耐熱性膜
Ｐｔ −Ｒｈ合金、１２・・・・・・Ｃｕ膜、１３・・
・・・・レジスト。FIG. 1 is a process diagram of manufacturing a molding die constructed according to the present invention. 10... Base material WC111... Heat resistant film Pt-Rh alloy, 12... Cu film, 13...
...Resist.
Claims (4)
し、前記母材を所望の形状に加工した後、被プレス材料
との反応性に乏しく、高温強度に優れた耐熱性の膜を母
材上に被覆し、前記耐熱性膜上に酸又はアルカリ溶液に
より簡単にエッチングされうる材料を所望の厚さに成膜
した後、前記材料より成る膜上にレジストを用いて所望
のパターンを形成する工程を経た後、酸又はアルカリ溶
液を用い材料より成る膜の一部をエッチングにより除去
する工程とそれに続く乾式エッチングによりレジスト及
び材料より成る膜を完全に除去する工程により作製した
金型を用いて光学素子をプレス成形して製造することを
特徴とする光学素子の製造方法。(1) A material with excellent heat resistance and strength at high temperatures is used as a base material, and after processing the base material into a desired shape, a heat-resistant film with poor reactivity with the pressed material and excellent high-temperature strength is produced. A material that can be easily etched with an acid or alkaline solution is formed on the heat-resistant film to a desired thickness, and then a resist is used to form a desired pattern on the film made of the material. After passing through the process of forming the resist, a part of the film made of the material is removed by etching using an acid or alkaline solution, followed by a process of completely removing the resist and the film made of the material by dry etching. 1. A method of manufacturing an optical element, which comprises press-molding and manufacturing an optical element using.
成分とするサーメット、ＴｉＣを主成分とするサーメッ
ト、Ｃｒ＿３Ｃ＿２を主成分とするサーメット、あるい
はＡｌ＿２Ｏ＿３を主成分とするサーメットであること
を特徴とする特許請求の範囲第（１）項記載の光学素子
の製造方法。(2) The base material is a cemented carbide mainly composed of WC, a cermet mainly composed of TiN, a cermet mainly composed of TiC, a cermet mainly composed of Cr_3C_2, or a cermet mainly composed of Al_2O_3 A method for manufacturing an optical element according to claim (1).
分とする合金膜、ちっ化物膜、炭化物膜あるいはホウ化
物膜であることを特徴とする特許請求の範囲第（ｌ）項
または第（２）項のいずれかに記載の光学素子の製造方
法。(3) The heat-resistant film is a platinum group metal, an alloy film containing a platinum group metal as a main component, a nitride film, a carbide film, or a boride film. A method for manufacturing an optical element according to any one of (2).
あるいは銅膜であることを特徴とする特許請求の範囲第
（１）項、第（２）項、または第（３）項のいずれかに
記載の光学素子の製造方法。(4) The film made of the material is a nickel film, an aluminum film,
Alternatively, the method for manufacturing an optical element according to any one of claims (1), (2), or (3), characterized in that it is a copper film.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30221987A JPH01145342A (en) | 1987-11-30 | 1987-11-30 | Production of optical element |
| US07/235,301 US4842633A (en) | 1987-08-25 | 1988-08-23 | Method of manufacturing molds for molding optical glass elements and diffraction gratings |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30221987A JPH01145342A (en) | 1987-11-30 | 1987-11-30 | Production of optical element |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01145342A true JPH01145342A (en) | 1989-06-07 |
| JPH0543650B2 JPH0543650B2 (en) | 1993-07-02 |
Family
ID=17906386
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP30221987A Granted JPH01145342A (en) | 1987-08-25 | 1987-11-30 | Production of optical element |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01145342A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0359928A (en) * | 1989-07-27 | 1991-03-14 | Matsushita Electric Ind Co Ltd | Gas discharge display element and its manufacture |
-
1987
- 1987-11-30 JP JP30221987A patent/JPH01145342A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0359928A (en) * | 1989-07-27 | 1991-03-14 | Matsushita Electric Ind Co Ltd | Gas discharge display element and its manufacture |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0543650B2 (en) | 1993-07-02 |
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