JPH01128433A - Formation of reverse image pattern - Google Patents
Formation of reverse image patternInfo
- Publication number
- JPH01128433A JPH01128433A JP28614087A JP28614087A JPH01128433A JP H01128433 A JPH01128433 A JP H01128433A JP 28614087 A JP28614087 A JP 28614087A JP 28614087 A JP28614087 A JP 28614087A JP H01128433 A JPH01128433 A JP H01128433A
- Authority
- JP
- Japan
- Prior art keywords
- exposure
- pattern
- exposed
- reversal
- ion beams
- 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
- 230000015572 biosynthetic process Effects 0.000 title 1
- 238000000034 method Methods 0.000 claims abstract description 27
- 238000010884 ion-beam technique Methods 0.000 claims abstract description 23
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 abstract description 15
- 229920003986 novolac Polymers 0.000 abstract description 10
- 150000002500 ions Chemical class 0.000 abstract description 8
- 239000000758 substrate Substances 0.000 abstract description 6
- 239000004065 semiconductor Substances 0.000 abstract description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 3
- 239000000243 solution Substances 0.000 abstract description 2
- 239000012047 saturated solution Substances 0.000 abstract 1
- 238000006243 chemical reaction Methods 0.000 description 6
- 239000007864 aqueous solution Substances 0.000 description 4
- 238000007796 conventional method Methods 0.000 description 4
- 229920006395 saturated elastomer Polymers 0.000 description 4
- 230000001133 acceleration Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 229920002120 photoresistant polymer Polymers 0.000 description 3
- 229920005601 base polymer Polymers 0.000 description 2
- 238000004132 cross linking Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000010894 electron beam technology Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229920003229 poly(methyl methacrylate) Polymers 0.000 description 2
- 239000004926 polymethyl methacrylate Substances 0.000 description 2
- ZNQVEEAIQZEUHB-UHFFFAOYSA-N 2-ethoxyethanol Chemical compound CCOCCO ZNQVEEAIQZEUHB-UHFFFAOYSA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 229910001423 beryllium ion Inorganic materials 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000006023 eutectic alloy Substances 0.000 description 1
- 230000001678 irradiating effect Effects 0.000 description 1
- JCCNYMKQOSZNPW-UHFFFAOYSA-N loratadine Chemical compound C1CN(C(=O)OCC)CCC1=C1C2=NC=CC=C2CCC2=CC(Cl)=CC=C21 JCCNYMKQOSZNPW-UHFFFAOYSA-N 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
- B29B17/02—Separating plastics from other materials
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
- B29B17/02—Separating plastics from other materials
- B29B2017/0213—Specific separating techniques
- B29B2017/0286—Cleaning means used for separation
- B29B2017/0289—Washing the materials in liquids
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
- B29K2105/06—Condition, form or state of moulded material or of the material to be shaped containing reinforcements, fillers or inserts
- B29K2105/065—Condition, form or state of moulded material or of the material to be shaped containing reinforcements, fillers or inserts containing impurities
Landscapes
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Mechanical Engineering (AREA)
- Photosensitive Polymer And Photoresist Processing (AREA)
- Electron Beam Exposure (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は集束イオンビームを用いた画像反転１＜ターン
形成方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an image inversion 1<turn forming method using a focused ion beam.
（従来技術とその問題点）
ポジ型レジストの画像反転を用いたパターン形成方法は
、一種類のポジ型レジストによってポジ型レジストパタ
ーン及びネガ型レジストパターンの両方が得られ、工程
及び設備の簡略化が計れるほか、光りソグラコイにおい
ては定在波の影響によるパターン寸法精度の悪化を抑え
ることができる等優れた特徴を有している。またパター
ン露光に集束イオンビーム露光を用いることにより、光
露光や電子ビーム露光では形成が困難な０．１μｍ程度
の微細なパターンの形成が可能である。(Prior art and its problems) A pattern forming method using image reversal of a positive resist allows both a positive resist pattern and a negative resist pattern to be obtained with one type of positive resist, simplifying the process and equipment. In addition, it has excellent features such as being able to measure the dimensional accuracy of the pattern due to the effects of standing waves. Further, by using focused ion beam exposure for pattern exposure, it is possible to form a fine pattern of about 0.1 μm, which is difficult to form with light exposure or electron beam exposure.
従来技術の工程を第４図を用いて説明する。The process of the prior art will be explained using FIG.
半導体基板４２に塗布されたポジ型レジスト４１（第４
図（ａ））に集束イオンビーム４３により適正露光量に
てパターン露光を行う（第４図（ｂ））。次にリバーサ
ルベークを行うことにより露光部分のネガ反転を起こさ
せる（第４図（Ｃ））。さらに遠紫外線光４４により一
括露光を行って、先のパターン露光での未露光部分を適
正露光量にて露光する（第４図（ｄ））。最後に現像を
行うことにより画像反転パターンが形成される（第４図
（ｅ））。しかしながら、この従来の方法では画像反転
を起こさせるためのりバーサルベーク及び、未露光部分
を除去するための遠紫外線光による一括露光を行ってお
り、ネガ型レジストを用いた通常のパターン形成方法と
比較して工程及び設備が複雑化するという問題点を有し
ていた。本発明の目的は、従来より工程の簡略化された
画像反転パターン形成方法を提供することにある。Positive resist 41 (fourth resist) coated on semiconductor substrate 42
In FIG. 4(a), pattern exposure is performed using a focused ion beam 43 at an appropriate exposure amount (FIG. 4(b)). Next, a reversal bake is performed to cause negative reversal of the exposed portion (FIG. 4(C)). Further, a batch exposure is performed with far ultraviolet light 44, and the unexposed portions in the previous pattern exposure are exposed at an appropriate exposure amount (FIG. 4(d)). Finally, by performing development, an image reversal pattern is formed (FIG. 4(e)). However, this conventional method involves a reversal bake to cause image reversal and a batch exposure with far ultraviolet light to remove unexposed areas, and is compared with a normal pattern forming method using a negative resist. However, this method has the problem of complicating the process and equipment. SUMMARY OF THE INVENTION An object of the present invention is to provide an image reversal pattern forming method that has simpler steps than the conventional method.
（問題を解決するための手段）
本発明は、ポジ型レジストと集束イオンビーム露光によ
るレジストの画像反転を用いたパターン形成方法におい
て、前記ポジ型レジストに適正露光量以上の集束イオン
ビームを露光する工程と、現像液により未露光部分を選
択的に除去しパターンを形成する工程とから成ることを
特徴とする、画像反転パターン形成方法である。(Means for Solving the Problems) The present invention provides a pattern forming method using a positive resist and image reversal of the resist by focused ion beam exposure, in which the positive resist is exposed to a focused ion beam having an appropriate exposure amount or more. This is an image reversal pattern forming method characterized by comprising a step of forming a pattern by selectively removing an unexposed portion using a developer.
（作用）
次に本発明の原理について第２図及び第３図を用いて説
明する。(Operation) Next, the principle of the present invention will be explained using FIGS. 2 and 3.
通常ポジ型レジストはベースとなるポリマーと感光基の
結合した構造をとっており、特定の波長の光又は荷電粒
子を照射することによって感光基の化学的反応を誘起し
特定の現像液に対して可溶性となる性質を持っている。Normally, positive resists have a structure in which a base polymer and a photosensitive group are combined, and by irradiating the photosensitive group with light of a specific wavelength or charged particles, a chemical reaction of the photosensitive group is induced, and it is applied to a specific developer. It has the property of being soluble.
しかしこのポジ型レジストに感光基の化学的反応を誘起
し、特定の現像液に対して可溶性となるのに必要なエネ
ルギー以上の露光エネルギーを与えると、感光基の反応
が進み前記現像液に対して不溶性となったり、ベースと
なるポリマー同士の架橋反応によりレジストの分子量が
増大し不溶化する等のネガ反応現象が起こる。また、こ
のネガ反応を起こさせるのに必要な露光エネルギーは、
そのエネルギー密度の低さから光露光によっては与える
ことができず、荷電粒子ビームによる必要がある。荷電
粒子ビームとして電子ビームとイオンビームを比較した
場合、電子とイオンの質量の大きな差に起因するレジス
ト中での単位体積当りのエネルギー密度の差によって、
電子を用いた場合イオンに比較して１〜２桁高い露光量
が必要となり近接効果、電荷蓄積の影響を強く受は微細
なパターンを清度良く形成することが困難である。第２
図は基板上に厚さ０．５μｍ塗布されたノボラック系ポ
ジ型レジスＩ−を加速エネルギー２６０ｋｅＶのＢｅ集
束イオンビームにより露光し、水酸化カリウム飽和水溶
液現像液：純水−１：３．５の混液中で１５０秒現像し
た結果得られた、露光量とレジスト残膜率の関係を示し
ている。ここでレジスト残膜率は塗布膜厚を基準とした
規格化残膜率で示しである。However, if this positive resist is exposed to more exposure energy than is necessary to induce a chemical reaction of the photosensitive groups and become soluble in a specific developer, the reaction of the photosensitive groups will proceed and the photoresist will become soluble in the developer. Negative reaction phenomena occur, such as the resist becoming insoluble, or the molecular weight of the resist increasing due to a crosslinking reaction between the base polymers, making the resist insoluble. Also, the exposure energy required to cause this negative reaction is
Due to its low energy density, it cannot be provided by optical exposure, and requires a charged particle beam. When comparing electron beams and ion beams as charged particle beams, due to the difference in energy density per unit volume in the resist due to the large difference in mass between electrons and ions,
When electrons are used, an exposure dose that is one to two orders of magnitude higher than that of ions is required, and electrons are strongly influenced by the proximity effect and charge accumulation, making it difficult to form fine patterns with good clarity. Second
The figure shows a novolac positive resist I- coated to a thickness of 0.5 μm on a substrate, exposed to a Be focused ion beam with an acceleration energy of 260 keV, and a potassium hydroxide saturated aqueous solution developer: pure water-1:3.5. It shows the relationship between the exposure amount and the resist remaining film rate obtained as a result of developing in a mixed solution for 150 seconds. Here, the resist remaining film rate is expressed as a normalized remaining film rate based on the coating film thickness.
この実験結果はノボラック系ポジ型レジストがイオンビ
ームによって適正露光量以上の露光量を与えられると、
急速にネガ反転を起こすことを示している。This experimental result shows that when a positive novolak resist is exposed to an ion beam with an exposure amount higher than the appropriate exposure amount,
This indicates that negative reversal occurs rapidly.
ネガ反転状態にあるレジストはポリマーの架橋による分
子量の増大、感光基の不溶化等、未露光部分に比較して
も更に不溶化の進んだ状態にあり、現像液を適当に選択
することにより未露光部分のみを選択的に除去すること
が可能である。第３図はノボラック系ポジ型レジストの
加速エネルギー２６０ｋｅＶ、Ｂｅイオンによる露光に
よってネガ反転を起こした部分と未露光部分の現像時間
と規格化残膜率の関係を示している。現像液は水酸化カ
リウム飽和水溶液現像液：純水−１：３゜５の混液を用
い、ネガ反転部分の露光量は１ Ｘ １０１３ｉｏｎｓ
／ ｃｍ２である。この実験結果は、ノボラック系ポジ
型レジストは未露光部分においても現像時間と共に残膜
率は直線的に低下するが、ネガ反転を起こした部分は全
く残膜率が低下していないことを示している。したがっ
てこれらの結果より、集束イオンビーム露光によってネ
ガ反転が起こるようにパターン露光を行うことによって
、その後に一括露光を行うこと無く画像反転パターンを
形成することができる。A resist in a negative reversal state is in a state where the molecular weight has increased due to crosslinking of the polymer, the photosensitive groups have become insolubilized, and the insolubilization has progressed further compared to the unexposed areas. It is possible to selectively remove only the FIG. 3 shows the relationship between the development time and the normalized residual film rate of a novolac positive type resist at an acceleration energy of 260 keV and a negative reversal area caused by exposure with Be ions and an unexposed area. The developer used was a mixture of potassium hydroxide saturated aqueous solution developer: pure water - 1:3°5, and the exposure amount for the negative reversal area was 1 x 1013 ions.
/cm2. The experimental results show that for novolak positive resists, the residual film rate decreases linearly with development time even in unexposed areas, but the residual film rate does not decrease at all in areas where negative reversal has occurred. There is. Therefore, based on these results, by performing pattern exposure so that negative reversal occurs by focused ion beam exposure, an image reversal pattern can be formed without performing a subsequent batch exposure.
（実施例）
以下、本発明の実施例について第１図を参照して説明す
る。(Example) Hereinafter, an example of the present invention will be described with reference to FIG.
第１図は本発明の詳細な説明するたの基板の部分断面図
である。まず、半導体基板１２上にノボラック系ポジ型
レジスト１１を厚さ０．５μｍ塗布し、１００°０５３
０分間ベイクする（第１図（ａ））。その後Ｂｅ集束イ
オンビーム１３によってノボラック系ポジ型レジス１−
１１にパターン露光を行う（第１図（ｂ）〉。その時Ｂ
ｅ集東イオンビーム１３の加速エネルギーは２６０ｋｅ
Ｖ、また露光量は１ ｘ １０１３ｉｏｎｓ／ ｃｍ２
とした。その後水酸化カリウム飽和水溶液現像液：純水
＝１’：３．５の混液中で３００秒現像することにより
、第１図（ｃ）に示した画像反転パターンを形成するこ
とができ、中０．１μｍの微細パターンまで得られる。FIG. 1 is a partial sectional view of a substrate for explaining the present invention in detail. First, a novolac-based positive resist 11 is applied to a thickness of 0.5 μm on the semiconductor substrate 12, and
Bake for 0 minutes (Figure 1(a)). Thereafter, the Be focused ion beam 13 is applied to the novolac positive resist 1-.
11, pattern exposure is performed (Fig. 1 (b)). At that time, B
The acceleration energy of e Shuto ion beam 13 is 260ke
V, and the exposure amount is 1 x 1013ions/cm2
And so. Thereafter, by developing for 300 seconds in a mixture of potassium hydroxide saturated aqueous solution developer: pure water = 1':3.5, the image reversal pattern shown in Fig. 1(c) can be formed. Fine patterns up to .1 μm can be obtained.
この場合、従来集束イオンビームによるパターン露光後
、ネガ反転を起こさせるためのりバーサルベーク工程及
び、未露光部分を除去するために紫外線光等を用いて行
っていた一括露光工程を省略することができるので、従
来方法に比べ設備及び工程の簡略化を計ることができた
。In this case, it is possible to omit the conventional baking process to cause negative reversal after pattern exposure using a focused ion beam, and the batch exposure process using ultraviolet light or the like to remove unexposed areas. Therefore, it was possible to simplify the equipment and process compared to the conventional method.
この実施例ではポジ型レジスト及び現像液にノボラック
系ポジ型レジスト（ＡＺレジスト）と水酸化カリウム飽
和水溶液現像液の組合せを用いたが、ノボラック系ポジ
型レジストとテトラメチルアンモニウムハイドロオキサ
イド等地の現像液の組合せ、またポリメチルメタクリレ
ート（ＰＭＭＡ）とエチルセロソルブ等地のポジ型レジ
スト及び現像液の組合せを用いても良い。またパターン
露光を行うめたの集束イオンビームのイオン種としてＢ
ｅイオンを用いたが、Ｌｉ、Ｓｉ、Ｇａ等等地単体金属
又は共晶合金イオン源から得られるイオン種を用いても
良い。In this example, a combination of a novolac-based positive resist (AZ resist) and a potassium hydroxide saturated aqueous solution developer was used as the positive resist and developer. A combination of solutions, or a combination of a positive resist such as polymethyl methacrylate (PMMA) and ethyl cellosolve, and a developer may be used. In addition, B is used as an ion species in the focused ion beam for pattern exposure.
Although e ions were used, ion species obtained from a single metal or eutectic alloy ion source such as Li, Si, or Ga may also be used.
（発明の効果）
以上説明したように、本発明によればポジ型しジスＩ・
と集束イオンビーム露光によるレジスＩ・の画像反転を
用いたパターン形成方法において、前記ポジ型レジスト
に適正露光量以上の集束イオンビームを露光する工程と
、現像液により未露光部分を選択的に除去しパターンを
形成する工程により、従来方法で行われていたりバーサ
ルベーク工程及び−括露光工程を省略することができ、
設備及び工程の簡略化を計ることができる。(Effects of the Invention) As explained above, according to the present invention, the positive type
and a pattern forming method using image reversal of resist I by focused ion beam exposure, which includes a step of exposing the positive resist to a focused ion beam of an appropriate exposure amount or more, and selectively removing unexposed portions with a developer. By forming the pattern, the versal baking process and the exposure process that are performed in the conventional method can be omitted.
Equipment and processes can be simplified.
第１図は本発明の方法の一実施例を説明するための基板
の部分断面図、第２図はＢｅ種束イオンビームの露光量
とノボラック系ポジ型レジストの現象後の規格化残膜率
の関係を示す図、第３図はＢｅ集東イオンビーム露光に
よる画像反転部分と未露光部分の現像時間と規格化残膜
率の関係を示す図、また第４図は従来技術の方法を説明
するための基板の部分断面図である。
１１・・・・・・・・・・・・ノボラック系ポジ型レジ
スト４１・・・・・・・・・・・・ポジ型レジスト１２
．４２・・・基板Fig. 1 is a partial cross-sectional view of a substrate for explaining an embodiment of the method of the present invention, and Fig. 2 shows the exposure amount of a Be species bundle ion beam and the normalized residual film rate after the phenomenon of a novolac positive resist. Figure 3 is a diagram showing the relationship between the development time and normalized residual film rate of the image inversion area and unexposed area by Be focused ion beam exposure, and Figure 4 explains the method of the prior art. FIG. 11・・・・・・・・・Novolak positive type resist 41・・・・・・・・・Positive resist 12
．． 42... Board
Claims (1)
ジストの画像反転を用いたパターン形成方法において、
前記ポジ型レジストに適正露光量以上の集束イオンビー
ムを露光する工程と、現像液により未露光部分を選択的
に除去しパターンを形成する工程とを備えたことを特徴
とする画像反転パターン形成方法。(1) In a pattern forming method using a positive resist and image reversal of the resist by focused ion beam exposure,
An image reversal pattern forming method comprising the steps of: exposing the positive resist to a focused ion beam with an appropriate exposure amount or more; and forming a pattern by selectively removing unexposed areas with a developer. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP28614087A JPH01128433A (en) | 1987-11-11 | 1987-11-11 | Formation of reverse image pattern |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP28614087A JPH01128433A (en) | 1987-11-11 | 1987-11-11 | Formation of reverse image pattern |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01128433A true JPH01128433A (en) | 1989-05-22 |
Family
ID=17700454
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP28614087A Pending JPH01128433A (en) | 1987-11-11 | 1987-11-11 | Formation of reverse image pattern |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01128433A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007505487A (en) * | 2003-09-09 | 2007-03-08 | シーエスジー ソーラー アクチェンゲゼルシャフト | Improved method for forming openings in organic resin materials |
-
1987
- 1987-11-11 JP JP28614087A patent/JPH01128433A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007505487A (en) * | 2003-09-09 | 2007-03-08 | シーエスジー ソーラー アクチェンゲゼルシャフト | Improved method for forming openings in organic resin materials |
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