[go: up one dir, main page]

JPH06163451A - Manufacture of semiconductor device - Google Patents

Manufacture of semiconductor device

Info

Publication number
JPH06163451A
JPH06163451A JP4312007A JP31200792A JPH06163451A JP H06163451 A JPH06163451 A JP H06163451A JP 4312007 A JP4312007 A JP 4312007A JP 31200792 A JP31200792 A JP 31200792A JP H06163451 A JPH06163451 A JP H06163451A
Authority
JP
Japan
Prior art keywords
film
resist film
mask
resist pattern
resist
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
Application number
JP4312007A
Other languages
Japanese (ja)
Inventor
Yukihiro Takao
幸弘 高尾
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.)
Sanyo Electric Co Ltd
Original Assignee
Sanyo Electric 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 Sanyo Electric Co Ltd filed Critical Sanyo Electric Co Ltd
Priority to JP4312007A priority Critical patent/JPH06163451A/en
Publication of JPH06163451A publication Critical patent/JPH06163451A/en
Pending legal-status Critical Current

Links

Landscapes

  • Exposure Of Semiconductors, Excluding Electron Or Ion Beam Exposure (AREA)
  • Exposure And Positioning Against Photoresist Photosensitive Materials (AREA)
  • Electrodes Of Semiconductors (AREA)
  • Drying Of Semiconductors (AREA)

Abstract

PURPOSE:To provide a method of stably forming a contact hole, wherein a resist pattern provided with a tapered plane is formed through a double exposure way, and the contact hole is formed through dry etching using the resist pattern concerned as a mask preventing a resist film from being lessened in thickness at development. CONSTITUTION:An insulating film 12 is covered with a resist film 13, an insoluble layer 14 is formed on the surface of the resist film 13 through an alkali treatment with developing solution, a full-surface exposure process and a mask exposure process are successively executed, and the insoluble layer 14 is enhanced in insolubility by a baking treatment. Then, a resist pattern 16 provided with a tapered plane is formed by development, the insulating film 12 is subjected to a dry etching process using the resist pattern 16 as a mask for the formation of a contact hole 17.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は半導体装置の製造方法に
関し、さらに詳しく言えば2重露光によりテーパー面を
つけたレジストパターンを絶縁膜上に形成し、該レジス
トパターンをマスクとしてドライエッチングすることに
より絶縁膜にコンタクト孔を形成する技術に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor device, and more specifically, a method of forming a resist pattern having a tapered surface on an insulating film by double exposure and performing dry etching using the resist pattern as a mask. The present invention relates to a technique for forming a contact hole in an insulating film.

【0002】[0002]

【従来の技術】半導体集積回路の微細化に伴い、絶縁膜
に形成したコンタクト孔を覆うAl膜のステップカバレ
ージを向上するためにコンタクト孔にテーパー面をつけ
る技術がある。この中で2重露光によりテーパー面をつ
けたレジストパターンを形成し、これをマスクとして絶
縁膜をドライエッチングすることにより絶縁膜にコンタ
クト孔を形成する方法が知られている。
2. Description of the Related Art With the miniaturization of semiconductor integrated circuits, there is a technique in which a contact hole is provided with a tapered surface in order to improve the step coverage of an Al film covering the contact hole formed in an insulating film. There is known a method in which a resist pattern having a tapered surface is formed by double exposure and a contact hole is formed in the insulating film by dry etching the insulating film using the resist pattern as a mask.

【0003】以下で、図面を参照して説明する。まず、
半導体基板(1)上に絶縁膜(2)を形成し、絶縁膜
(2)上の全面にレジスト膜(3)を形成する(図
9)。次に、露光装置としてステッパーを用い第1露光
として全面露光を行い、第2露光としてマスク露光を行
い、現像を行うことによってテーパー面のついたレジス
トパターン(3A)が形成される(図10)。この後、
レジストパターン(3A)をマスクとして絶縁膜(2)
をドライエッチングすることにより、テーパー面のつい
たコンタクト孔を得ることができる。
A description will be given below with reference to the drawings. First,
An insulating film (2) is formed on the semiconductor substrate (1), and a resist film (3) is formed on the entire surface of the insulating film (2) (FIG. 9). Next, a stepper is used as an exposure device to perform overall exposure as first exposure, mask exposure as second exposure, and development to form a resist pattern (3A) having a tapered surface (FIG. 10). . After this,
Insulating film (2) using resist pattern (3A) as a mask
By dry etching, it is possible to obtain a contact hole having a tapered surface.

【0004】なお上述した技術は、例えば1992年春
季日本応用物理学会講演予稿集の516頁に記載があ
る。
The above-mentioned technique is described, for example, on page 516 of the proceedings of the 1992 Spring Japanese Society of Applied Physics.

【0005】[0005]

【発明が解決しようとする課題】しかしながら、第1露
光としての全面露光ではコンタクト孔が形成される領域
以外に対しても露光が行われるので、レジスト膜(3)
の感光が進み、現像後では膜減り(d1−d2)が生じ
る。本願発明者の実験によれば、全面露光の露光量の増
加に伴いテーパー角(θ)が小さくなるが、テーパー角
(θ)として最適である露光条件40mJ〜45mJに
おいては、6500Å〜8000Åという大きな膜減り
が生じるという問題点がある(図8の曲線Aを参照)。
このため、多層配線によって絶縁膜(2)の表面に凹凸
がある場合には凸部分でレジストパターン(3A)が薄
くなり、絶縁膜(2)が露出するおそれがある。
However, in the whole surface exposure as the first exposure, the exposure is performed not only in the region where the contact hole is formed, so that the resist film (3) is used.
The photosensitivity of ( 1 ) advances, and a film loss (d 1 -d 2 ) occurs after development. According to an experiment conducted by the inventor of the present application, the taper angle (θ) becomes smaller as the exposure amount of the entire surface exposure increases. There is a problem that film loss occurs (see curve A in FIG. 8).
Therefore, when the surface of the insulating film (2) is uneven due to the multi-layer wiring, the resist pattern (3A) becomes thin at the convex portion, and the insulating film (2) may be exposed.

【0006】この対策として、レジスト膜(3)をあら
かじめ1.8μm位に厚く形成しておくことが考えられ
るが、これでは解像性が劣化するので微細化には不向き
である。本発明は、上記の問題点に鑑みてなされたもの
であり、現像後のレジスト膜の膜減りの問題を改善し、
良好なテーパー面を有したコンタクト孔を形成すること
を目的としている。
As a countermeasure against this, it is conceivable to form the resist film (3) to a thickness of about 1.8 μm in advance, but this deteriorates the resolution and is not suitable for miniaturization. The present invention has been made in view of the above problems, and improves the problem of film loss of the resist film after development,
The purpose is to form a contact hole having a good tapered surface.

【0007】[0007]

【課題を解決するための手段】
本発明は、上述した問題点に鑑みてな
されたものであり、図1に示した工程フロー図の如く、
全面露光前にアルカリ処理によりレジスト膜(13)の
表面に難溶層(14)を形成する工程を追加し、さらに
現像前に難溶層(14)の難溶度を高めるためのベーク
工程を追加したことを特徴とするものである。
[Means for Solving the Problems]
The present invention has been made in view of the above-mentioned problems, and as shown in the process flow chart of FIG.
Before the whole surface exposure, a step of forming a hardly soluble layer (14) on the surface of the resist film (13) by an alkali treatment is added, and a baking step for increasing the poor solubility of the slightly soluble layer (14) before development is performed. It is characterized by the addition.

【0008】[0008]

【作用】本願発明者による実験結果(図8参照)による
と、アルカリ処理によりレジスト膜の表面に難溶層を形
成する工程を追加することにより、コンタクト領域以外
の領域での現像が遅く進むので、従来例(曲線A)と比
べて約2000Å膜減りが少なくなる(曲線B)。そし
て、現像前に難溶層の難溶度を高めるためのベーク工程
を追加したことにより、その領域での現像がさらに遅く
進むようになるので、結果としてさらに大幅に膜減りを
少なくすることができる(曲線C)。
According to the experimental results (see FIG. 8) by the inventor of the present application, by adding the step of forming the hardly soluble layer on the surface of the resist film by the alkali treatment, the development in the region other than the contact region proceeds slowly. Compared with the conventional example (curve A), the film loss is reduced by about 2000Å (curve B). Then, by adding a baking step for increasing the solubility of the hardly soluble layer before the development, the development in that region will proceed further slowly, and as a result, the film loss can be further greatly reduced. Yes (curve C).

【0009】これにより、絶縁膜の凸部分でレジスト膜
が薄くなって絶縁膜が露出することが防止される。
This prevents the resist film from being thinned at the convex portions of the insulating film and exposing the insulating film.

【0010】[0010]

【実施例】次に、本発明の実施例を図面を参照して説明
する。半導体基板(11)上に減圧CVD法によりBP
SG膜等よりなる絶縁膜(12)を形成し、絶縁膜(1
2)上を約1.1μmの膜厚を有するレジスト膜(1
3)で被覆し、アルカリ処理によってレジスト膜(1
3)の表面に難溶層(14)を形成した(図2)。
Embodiments of the present invention will now be described with reference to the drawings. BP is formed on the semiconductor substrate (11) by the low pressure CVD method.
An insulating film (12) made of an SG film or the like is formed, and the insulating film (1
2) a resist film (1
3), and the resist film (1
A poorly soluble layer (14) was formed on the surface of 3) (FIG. 2).

【0011】このアルカリ処理としては、例えばテトラ
メチルアンモニウムハイドロオキサイド(TMAH)N
(CH3)4OHを含む現像液を使用し、10秒〜60秒
の処理時間で行った。次に露光装置としてステッパーを
用い、透明ガラスマスクを通して全面露光を行った。こ
の全面露光は、テーパーをつけるために行うものであ
り、マスク露光よりも少ない露光量35mJ〜45mJ
で行われる(図3)。
The alkali treatment is, for example, tetramethylammonium hydroxide (TMAH) N.
A developing solution containing (CH 3 ) 4 OH was used and the processing time was 10 seconds to 60 seconds. Next, using a stepper as an exposure device, the entire surface was exposed through a transparent glass mask. This whole surface exposure is performed to make a taper, and the exposure amount is 35 mJ to 45 mJ which is smaller than the mask exposure.
(Fig. 3).

【0012】次にコンタクトマスク(15)を半導体基
板(11)上に配置してステッパーによりマスク露光を
行った。露光量は、80mJ〜90mJである(図
4)。次に難溶層(14)の現像液に対する難溶度を高
めるため、換言すれば現像液による溶解速度を下げるた
めに、100℃、60秒のベーク処理を行った後に、T
MAHを含む現像液により現像した。このようにして、
テーパー面のついたレジストパターン(16)が形成さ
れた(図5)。
Next, the contact mask (15) was placed on the semiconductor substrate (11) and mask exposure was performed by a stepper. The exposure amount is 80 mJ to 90 mJ (FIG. 4). Next, in order to increase the poor solubility of the poorly soluble layer (14) in the developing solution, in other words, to reduce the dissolution rate by the developing solution, after baking treatment at 100 ° C. for 60 seconds, T
It was developed with a developer containing MAH. In this way
A resist pattern (16) having a tapered surface was formed (FIG. 5).

【0013】本発明によれば、難溶層(14)の形成と
その後のベーク処理により、膜減り(d1ーd2)が大幅
に抑制されており(図8の曲線C)、しかも全面露光量
が40mJ〜45mJにおいてはテーパー角(θ)30
°〜40°を有する良好なテーパー面が得られるのであ
る。また、従来のように膜減りを補うためにあらかじめ
レジスト膜(13)の膜厚d1を厚くする必要がないの
で、微細化に対応した解像性を確保できる。
According to the present invention, the film loss (d 1 -d 2 ) is significantly suppressed by the formation of the hardly soluble layer (14) and the subsequent baking treatment (curve C in FIG. 8), and moreover, the entire surface. The taper angle (θ) is 30 when the exposure amount is 40 mJ to 45 mJ.
A good tapered surface having an angle of 40 ° is obtained. In addition, since it is not necessary to increase the film thickness d 1 of the resist film (13) in advance in order to compensate for the film loss as in the conventional case, it is possible to secure the resolution corresponding to the miniaturization.

【0014】なお、本発明における現像過程は以下のよ
うに起こると考えられる。まず、難溶層(14)はコン
タクトマスクによる露光領域から離れた領域では弱い全
面露光しか受けていないので現像速度が非常に遅い。こ
れが膜減りが少ない原因である。一方コンタクトマスク
による露光領域では難溶層(14)は2重露光を受けて
いるので比較的早く溶解する。そして、難溶層(14)
が溶解した部分からその下方のレジスト膜(13)の現
像が急速に進む。この領域のレジスト膜(13)は上述
した2重露光を受けているので縦方向だけでなく横方向
にも溶解が進むのでテーパー面のついたレジストパター
ン(16)が形成されるのである。
The developing process in the present invention is considered to occur as follows. First, since the poorly soluble layer (14) receives only weak overall exposure in a region away from the exposure region by the contact mask, the developing speed is very slow. This is the cause of less film loss. On the other hand, in the area exposed by the contact mask, the refractory layer (14) undergoes double exposure and therefore dissolves relatively quickly. And poorly soluble layer (14)
The development of the resist film (13) therebelow rapidly progresses from the dissolved portion. Since the resist film (13) in this region has been subjected to the double exposure described above, the dissolution progresses not only in the vertical direction but also in the horizontal direction, so that the resist pattern (16) having a tapered surface is formed.

【0015】このようにしてレジストパターン(16)
を形成した後、これをマスクとして絶縁膜(12)を例
えばCHF3ガスを用いたプラズマエッチングより選択
エッチングした。このプラズマエッチングの結果、レジ
ストパターン(16)の断面形状が絶縁膜(12)に転
写され、テーパー面のついたコンタクト孔(17)が形
成された(図6)。本発明によれば、レジストパターン
(16)の膜減りが約2500Å(全面露光量45m
J)に抑えられているので、絶縁膜(12)に凹凸があ
ってもコンタクト領域以外で絶縁膜(12)がプラズマ
に晒されエッチングされるおそれがない。これにより、
安定してコンタクト孔(17)を形成できるのである。
In this way, the resist pattern (16)
After forming, the insulating film (12) was selectively etched by plasma etching using, for example, CHF 3 gas using this as a mask. As a result of this plasma etching, the cross-sectional shape of the resist pattern (16) was transferred to the insulating film (12), and a contact hole (17) having a tapered surface was formed (FIG. 6). According to the present invention, the film loss of the resist pattern (16) is about 2500Å (entire exposure amount 45 m
Since it is suppressed to J), even if the insulating film (12) has irregularities, there is no possibility that the insulating film (12) will be exposed to plasma and etched except in the contact region. This allows
The contact hole (17) can be stably formed.

【0016】次にレジストパターン(16)を有機溶剤
で除去した後、全面に蒸着またはスパッタ−法によりア
ルミニウムの金属薄膜で被覆し、所望のパターンにエッ
チングして金属配線層(18)を形成した。
Next, after removing the resist pattern (16) with an organic solvent, the entire surface is covered with a metal thin film of aluminum by vapor deposition or a sputtering method, and a desired pattern is etched to form a metal wiring layer (18). .

【0017】[0017]

【発明の効果】以上説明したように、本発明によれば2
重露光前にレジスト膜(13)の表面に難溶層(14)
を形成し、2重露光後にベーク処理を行うことにより、
現像時の膜減りを大幅に少なくし、かつ良好なテーパー
面が得られる。これにより、絶縁膜(12)に凹凸があ
る場合でもテーパー面のついたコンタクト孔(17)を
安定して形成できる利点を有する。
As described above, according to the present invention, 2
Hardly soluble layer (14) on the surface of resist film (13) before double exposure
And by performing a baking treatment after double exposure,
The film loss during development is significantly reduced, and a good tapered surface can be obtained. This has an advantage that the contact hole (17) having a tapered surface can be stably formed even when the insulating film (12) has irregularities.

【0018】また、従来のように現像時の膜減りを補う
ためにあらかじめレジスト膜(13)を厚く形成する必
要がないので、解像性を確保し微細なコンタクト孔(1
7)を形成できるという利点も有している。
Further, since it is not necessary to previously form a thick resist film (13) in order to compensate for the film loss at the time of development as in the conventional case, the resolution is secured and the fine contact hole (1) is formed.
It also has the advantage that 7) can be formed.

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

【図1】本発明の半導体装置の製造方法を示す工程フロ
ー図である。
FIG. 1 is a process flow chart showing a method for manufacturing a semiconductor device of the present invention.

【図2】本発明の半導体装置の製造方法の実施例を示す
第1の断面図である。
FIG. 2 is a first cross-sectional view showing an embodiment of a method for manufacturing a semiconductor device of the present invention.

【図3】本発明の半導体装置の製造方法の実施例を示す
第2の断面図である。
FIG. 3 is a second cross-sectional view showing an embodiment of the method for manufacturing a semiconductor device of the present invention.

【図4】本発明の半導体装置の製造方法の実施例を示す
第3の断面図である。
FIG. 4 is a third cross-sectional view showing the embodiment of the method for manufacturing the semiconductor device of the present invention.

【図5】本発明の半導体装置の製造方法の実施例を示す
第4の断面図である。
FIG. 5 is a fourth cross-sectional view showing the embodiment of the method for manufacturing the semiconductor device of the present invention.

【図6】本発明の半導体装置の製造方法の実施例を示す
第5の断面図である。
FIG. 6 is a fifth cross-sectional view showing the embodiment of the method for manufacturing the semiconductor device of the present invention.

【図7】本発明の半導体装置の製造方法の実施例を示す
第6の断面図である。
FIG. 7 is a sixth cross-sectional view showing the embodiment of the method for manufacturing the semiconductor device of the present invention.

【図8】レジスト膜の現像による膜減り特性を示す図で
ある。
FIG. 8 is a diagram showing a film reduction characteristic due to development of a resist film.

【図9】従来例に係る半導体装置の製造方法を示す第1
の断面図である。
FIG. 9 is a first diagram showing a method of manufacturing a semiconductor device according to a conventional example.
FIG.

【図10】従来例に係る半導体装置の製造方法の示す第
1の断面図である。
FIG. 10 is a first cross-sectional view showing the method for manufacturing the semiconductor device according to the conventional example.

───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.5 識別記号 庁内整理番号 FI 技術表示箇所 H01L 21/302 M 9277−4M ─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. 5 Identification code Internal reference number FI technical display location H01L 21/302 M 9277-4M

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 半導体基板上に形成された絶縁膜上をレ
ジスト膜で被覆する工程と、 アルカリ処理により前記レジスト膜の表面に難溶層を形
成する工程と、 前記レジスト膜を全面露光する工程と、 前記レジスト膜をマスク露光する工程と、 前記難溶層の難溶度を高めるためにベークする工程と、 前記レジスト膜を現像する工程と、 前記レジスト膜をマスクとしてドライエッチングして前
記絶縁膜にコンタクト孔を形成する工程とを有すること
を特徴とする半導体装置の製造方法。
1. A step of coating an insulating film formed on a semiconductor substrate with a resist film, a step of forming a refractory layer on the surface of the resist film by an alkali treatment, and a step of exposing the entire surface of the resist film. A step of exposing the resist film with a mask, a step of baking the resist film to increase the solubility of the sparingly soluble layer, a step of developing the resist film, and a step of dry etching using the resist film as a mask to perform the insulation. And a step of forming a contact hole in the film.
JP4312007A 1992-11-20 1992-11-20 Manufacture of semiconductor device Pending JPH06163451A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4312007A JPH06163451A (en) 1992-11-20 1992-11-20 Manufacture of semiconductor device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4312007A JPH06163451A (en) 1992-11-20 1992-11-20 Manufacture of semiconductor device

Publications (1)

Publication Number Publication Date
JPH06163451A true JPH06163451A (en) 1994-06-10

Family

ID=18024090

Family Applications (1)

Application Number Title Priority Date Filing Date
JP4312007A Pending JPH06163451A (en) 1992-11-20 1992-11-20 Manufacture of semiconductor device

Country Status (1)

Country Link
JP (1) JPH06163451A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7459849B2 (en) 2000-09-18 2008-12-02 Semiconductor Energy Laboratory Co., Ltd. Display device and method of fabricating the display device

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7459849B2 (en) 2000-09-18 2008-12-02 Semiconductor Energy Laboratory Co., Ltd. Display device and method of fabricating the display device
US7514868B2 (en) 2000-09-18 2009-04-07 Semiconductor Energy Laboratory Co., Ltd. Display device and method of fabricating the display device
US8044588B2 (en) 2000-09-18 2011-10-25 Semiconductor Energy Laboratory Co., Ltd. Display device and method of fabricating the display device
US8421352B2 (en) 2000-09-18 2013-04-16 Semiconductor Energy Laboratory Co., Ltd. Light emitting device
US9263503B2 (en) 2000-09-18 2016-02-16 Semiconductor Energy Laboratory Co., Ltd. Display device and method of fabricating the display device

Similar Documents

Publication Publication Date Title
EP0072933B1 (en) Method for photolithographic pattern generation in a photoresist layer
JPS63236319A (en) Manufacture of semiconductor device
JPH06163451A (en) Manufacture of semiconductor device
US20050183960A1 (en) Polymer film metalization
KR100187677B1 (en) Forming method of diffusion prevention layer
JP2740008B2 (en) Method of forming opening for semiconductor element
JPH07254605A (en) Wiring formation method
JP2521329B2 (en) Method for manufacturing semiconductor device
KR100282417B1 (en) Method for manufacturing semiconductor device
JP2570709B2 (en) Etching method
KR970004428B1 (en) A method for manufacturing semiconductor devices
JP3109506B2 (en) Pattern formation method
KR0156106B1 (en) Pattern Forming Method in Metallization Process
KR0144232B1 (en) Method of forming fine pattern of semiconductor device
KR0144140B1 (en) Metal wiring method
JPS5950053B2 (en) Photo engraving method
JP3149601B2 (en) Method for forming contact hole in semiconductor device
KR0144019B1 (en) Forming method of metal connection in semiconductor
JP3046114B2 (en) Method for manufacturing semiconductor integrated circuit device
JPH045260B2 (en)
KR100278742B1 (en) Method of forming fine pattern of highly reflective material
JPH10221851A (en) Pattern formation method
JPH0123944B2 (en)
KR20000009177A (en) Method for forming metal line of semiconductor device
JPS6351640A (en) Manufacture of semiconductor element