JPH0347966A - Formation of thin al-cu alloy film - Google Patents
Formation of thin al-cu alloy filmInfo
- Publication number
- JPH0347966A JPH0347966A JP18207589A JP18207589A JPH0347966A JP H0347966 A JPH0347966 A JP H0347966A JP 18207589 A JP18207589 A JP 18207589A JP 18207589 A JP18207589 A JP 18207589A JP H0347966 A JPH0347966 A JP H0347966A
- Authority
- JP
- Japan
- Prior art keywords
- film
- thin
- alloy
- thin film
- raw material
- 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
- 229910000881 Cu alloy Inorganic materials 0.000 title claims description 8
- 230000015572 biosynthetic process Effects 0.000 title 1
- 239000010409 thin film Substances 0.000 claims abstract description 26
- 229910052802 copper Inorganic materials 0.000 claims abstract description 21
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 13
- 239000007789 gas Substances 0.000 claims abstract description 11
- 239000010949 copper Substances 0.000 claims description 26
- 239000002994 raw material Substances 0.000 claims description 20
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 11
- 238000005229 chemical vapour deposition Methods 0.000 claims description 6
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 5
- 239000010408 film Substances 0.000 abstract description 17
- 230000005012 migration Effects 0.000 abstract description 12
- 238000013508 migration Methods 0.000 abstract description 12
- 229910045601 alloy Inorganic materials 0.000 abstract description 8
- 239000000956 alloy Substances 0.000 abstract description 8
- 229910018182 Al—Cu Inorganic materials 0.000 abstract description 7
- 238000010438 heat treatment Methods 0.000 abstract description 3
- 239000007858 starting material Substances 0.000 abstract 4
- 238000009792 diffusion process Methods 0.000 abstract 1
- 230000001105 regulatory effect Effects 0.000 abstract 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 8
- 239000010410 layer Substances 0.000 description 5
- 238000004544 sputter deposition Methods 0.000 description 5
- 235000010210 aluminium Nutrition 0.000 description 4
- 239000001257 hydrogen Substances 0.000 description 4
- 229910052739 hydrogen Inorganic materials 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- TUTOKIOKAWTABR-UHFFFAOYSA-N dimethylalumane Chemical compound C[AlH]C TUTOKIOKAWTABR-UHFFFAOYSA-N 0.000 description 3
- 238000000354 decomposition reaction Methods 0.000 description 2
- 238000005979 thermal decomposition reaction Methods 0.000 description 2
- 238000005275 alloying Methods 0.000 description 1
- 125000004429 atom Chemical group 0.000 description 1
- ORVACBDINATSAR-UHFFFAOYSA-N dimethylaluminum Chemical compound C[Al]C ORVACBDINATSAR-UHFFFAOYSA-N 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 239000011229 interlayer Substances 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 238000004518 low pressure chemical vapour deposition Methods 0.000 description 1
- YSTQWZZQKCCBAY-UHFFFAOYSA-L methylaluminum(2+);dichloride Chemical compound C[Al](Cl)Cl YSTQWZZQKCCBAY-UHFFFAOYSA-L 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- MCULRUJILOGHCJ-UHFFFAOYSA-N triisobutylaluminium Chemical compound CC(C)C[Al](CC(C)C)CC(C)C MCULRUJILOGHCJ-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Internal Circuitry In Semiconductor Integrated Circuit Devices (AREA)
- Chemical Vapour Deposition (AREA)
- Electrodes Of Semiconductors (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野]
本発明は集積回路装置などを構成する配線用のCu合金
薄膜を形成する方法に関するものであAl
る。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for forming a Cu alloy thin film for wiring constituting an integrated circuit device or the like.
[従来の技術]
集積回路装置の配線を形成するためのアルミニウム系薄
膜は段差部で被覆性よく堆積される必要があり、このた
めの方法としてバイアススパッタリング法(J、 El
ect、rochem、 Soc、誌、1985年第1
32巻、1466頁所載論文)や化学気相成長法(J、
Electrochem、 Soc、誌、1984年第
131巻、2175頁所載論文)(以降CVD法と略記
する)か検討されている。[Prior Art] Aluminum-based thin films for forming interconnections in integrated circuit devices must be deposited with good coverage at stepped portions, and bias sputtering (J, El) is a method for this purpose.
ect, rochem, soc, magazine, 1985 no.
Volume 32, page 1466) and chemical vapor deposition (J,
Electrochem, Soc, 1984, Vol. 131, p. 2175) (hereinafter abbreviated as CVD method) is being considered.
また、段差被覆性がよいCVD法ではAlに81を添加
した報告(第35回応用物理学関係連合講演会講演予稿
集第2冊分p605講演番号28a−v−6)がある。In addition, in the CVD method, which provides good step coverage, there is a report on adding 81 to Al (35th Applied Physics Association Lecture Proceedings, Volume 2, p605, Lecture No. 28a-v-6).
しかしながら、LSIの微細化に伴い、使用される配線
幅や電極のコンタクト孔の微細化が必要であり、このた
め、電流密度の増大に起因するエレクI・ロマイグレー
ション及びストレスマイグレーションが問題となってい
る。一般にAlは原子量が小さく、動き易いため上記の
ような問題が生じる。However, with the miniaturization of LSIs, it is necessary to miniaturize the width of the wiring used and the contact holes of the electrodes, and as a result, electric I/ROM migration and stress migration caused by increased current density have become problems. There is. In general, Al has a small atomic weight and is mobile, which causes the above-mentioned problems.
スパッタリング法ではAlへのCu添加がマイグレーシ
ョンに対して効果があることが知られているが、通常の
スパッタリング法では1.、sIの微細化に対応できな
い。バイアススパッタリング法でも同様の添加が可能で
あるが、バイアスを加えるため試料は、イオンや電子等
の荷電粒子の衝撃に曝されて、素子や配線に特性変動を
生じ、特に配線においてはマイグレーション耐性が劣化
することが知られている。In the sputtering method, it is known that adding Cu to Al is effective against migration, but in the normal sputtering method, 1. , cannot cope with miniaturization of sI. Similar dosing is possible using the bias sputtering method, but since the bias is applied, the sample is exposed to the bombardment of charged particles such as ions and electrons, which causes characteristic changes in elements and wiring, and especially in wiring, migration resistance is reduced. known to deteriorate.
また、Al−3i膜は、段差被覆性のよいCVDにより
形成が報告されているが、通常必要とされるプロセス温
度ではコンタクト部においてSiが析出し、コンタクト
抵抗の増加がみられ、コンタクト不良となることが報告
されている(Digest of Technical
Papers、1986 Symposium on
VLSI Technology論文番号V−4,p
p、55−56. May 1986)。In addition, it has been reported that Al-3i film can be formed by CVD with good step coverage, but at the normally required process temperature, Si precipitates in the contact area, increasing contact resistance and causing contact failure. It has been reported that (Digest of Technical
Papers, 1986 Symposium on
VLSI Technology paper number V-4, p
p, 55-56. May 1986).
このような理由から段差被覆性及びマイグレーション耐
性を同時に満足する技術は今までに実現されていない。For these reasons, a technique that satisfies step coverage and migration resistance at the same time has not been realized to date.
本発明の目的は段差被覆性及びマイグレーション耐性を
同時に満足したAl −Cu合金薄膜形成方法を提供す
ることにある。An object of the present invention is to provide a method for forming an Al--Cu alloy thin film that satisfies step coverage and migration resistance at the same time.
上記目的を達成するため本発明のAl −Cu合金薄膜
形成方法においては、有機アルミニウムをアルミニウム
の原料とし、ヘキサフロロアセチルアセトナート銅(C
u(hfa)、を銅の原料とし、それぞれの原料ガスを
混合させずに化学気相堆積法を用いて、これら原料から
Al、 Cu薄膜を交互に多層薄膜状に形成後、前記多
層薄膜を加熱してAl−Cu合金薄膜を生成させるもの
である。In order to achieve the above object, in the method for forming an Al-Cu alloy thin film of the present invention, organic aluminum is used as a raw material for aluminum, copper hexafluoroacetylacetonate (C
U(hfa) is used as a raw material for copper, and after forming Al and Cu thin films alternately from these raw materials into a multilayer thin film using a chemical vapor deposition method without mixing the respective raw material gases, the multilayer thin film is It is heated to generate an Al-Cu alloy thin film.
[作用]
本発明においては、Al原料の分解温度が250℃以上
、ヘキサフロロアセチルアセトナート銅(Cu(hfa
)、の分解温度が250℃以上であり、基板温度を25
0℃以上にしておけばAl及び銅が熱分解により堆積す
ることを利用している。しかしながら、原料ガス同士を
混合するとAlの酸化反応が進み、膜中に酸化Alが堆
積するおそれがある。そのため、気相中でこれら原料ガ
スを混合しないように、それぞれの原料ガスを間欠的に
交互に流すことによりkQと銅の薄膜とを交互に形成す
る。次に、加熱することによりAlと銅とを相互に拡散
させAft −Cu合金を生成する。また、それぞれの
原料ガスの流量を制御することにより、膜厚を制御し、
加熱後の堆積膜中のAl及び銅の成分比を制御すること
ができる。[Function] In the present invention, the decomposition temperature of the Al raw material is 250°C or higher, and copper hexafluoroacetylacetonate (Cu(hfa)
), the decomposition temperature is 250℃ or higher, and the substrate temperature is 25℃ or higher.
It takes advantage of the fact that Al and copper are deposited by thermal decomposition if the temperature is kept above 0°C. However, when the raw material gases are mixed, the oxidation reaction of Al progresses, and there is a possibility that Al oxide may be deposited in the film. Therefore, kQ and copper thin films are alternately formed by intermittently and alternately flowing each raw material gas so as not to mix these raw material gases in the gas phase. Next, by heating, Al and copper are mutually diffused to form an Aft-Cu alloy. In addition, by controlling the flow rate of each source gas, the film thickness can be controlled.
The component ratio of Al and copper in the deposited film after heating can be controlled.
スパッタにより形成されたAl−Cu合金膜がストレス
マイグレーションに有効と報告されている(Proce
eding of 5econd Internati
onal IEEE VLSIMulilevel I
nterconnection Conference
pp、l73179、 June 1985)。It has been reported that an Al-Cu alloy film formed by sputtering is effective for stress migration (Proce
eding of 5th century International
onal IEEE VLSIMulilevel I
Interconnection Conference
pp, l73179, June 1985).
これは、Cuの添加でAfl原子の移動が抑えられるの
でAlのマイグレーション耐性が強くなると考えられる
。したがって、CVDで形成されたAn−Cu合金膜も
マイグレーション耐性に優れている。そのうえ、CVD
によって膜を形成するため、膜の段差被覆性も良好であ
る。This is thought to be due to the fact that the addition of Cu suppresses the movement of Afl atoms, thereby increasing the migration resistance of Al. Therefore, the An-Cu alloy film formed by CVD also has excellent migration resistance. Moreover, CVD
Since the film is formed using the above method, the step coverage of the film is also good.
〔実施例] 以下に図を参照して本発明の詳細な説明する。〔Example] The present invention will be described in detail below with reference to the drawings.
第1図はAl−Cu合金薄膜の形成を実施するためのガ
ス供給系及び減圧CVD装置の構成図である。FIG. 1 is a configuration diagram of a gas supply system and a low pressure CVD apparatus for forming an Al--Cu alloy thin film.
1は水素ガスのボンベ、2及び3はそれぞれAl原料及
び銅原料を封入したバブラ容器、4及び5はこれらバブ
ラ容器の温度を一定に保つための温度調整器、6.7及
び8は水素ガスの流量を調節するマスフローコントロー
ラ、9.lO及び11はそれぞれ水素、 Al原料を含
む水素及び銅原料を含む水素を成長室に導入するための
エアーバルブ、12はこれら3つのバルブの開閉を制御
するバルブ開閉制御装置、13は成長室、14はウェハ
、15はウェハを加熱し温度を一定に保つヒータ、16
は排気系である。1 is a hydrogen gas cylinder, 2 and 3 are bubbler containers filled with Al raw material and copper raw material, respectively, 4 and 5 are temperature regulators to keep the temperature of these bubbler containers constant, and 6.7 and 8 are hydrogen gas. 9. a mass flow controller that adjusts the flow rate of the flow rate; IO and 11 are air valves for introducing hydrogen, hydrogen containing an Al raw material, and hydrogen containing a copper raw material into the growth chamber, respectively; 12 is a valve opening/closing control device that controls opening and closing of these three valves; 13 is a growth chamber; 14 is a wafer, 15 is a heater that heats the wafer and keeps the temperature constant, 16
is the exhaust system.
図において、まず、バブラ容器2にジメチルアルミハイ
ドライドを封入し、水素ガスの流量をマスフローコント
ローラ6で制御しながらフローさせ、バブラ容器2で原
料の蒸気圧成分を分圧比で混合する。また、容器3にヘ
キサフロロアセチルアセトナート銅を封入し、水素ガス
の流量をマスフローコントローラ8で制御しながらフロ
ーさせバルブ9で原料の蒸気圧成分を分圧比で混合する
。In the figure, first, dimethylaluminum hydride is sealed in a bubbler container 2, and hydrogen gas is caused to flow while controlling the flow rate with a mass flow controller 6, and the vapor pressure components of the raw materials are mixed in the bubbler container 2 at a partial pressure ratio. Further, copper hexafluoroacetylacetonate is sealed in the container 3, and hydrogen gas is caused to flow while controlling the flow rate with a mass flow controller 8, and the vapor pressure components of the raw materials are mixed at a partial pressure ratio with a valve 9.
次に、成長室13内の圧力を3 Torrに保ち、ジメ
チルアルミハイドライドを含む水素ガス流量を前記マス
フローコントローラ6で603CCMに制御する。Next, the pressure in the growth chamber 13 is maintained at 3 Torr, and the flow rate of hydrogen gas containing dimethylaluminum hydride is controlled to 603 CCM by the mass flow controller 6.
成長中は、バブラ容器2の温度は温度調整器4で25℃
に、容器3の温度は温度調整器5で80℃に保たせる。During growth, the temperature of bubbler container 2 is kept at 25°C by temperature regulator 4.
Next, the temperature of the container 3 is maintained at 80° C. by a temperature regulator 5.
また、このとき成長室13内のAl原料ガスの分圧は0
. I Torr、成長室13内のヘキサフロロアセチ
ルアセトナート銅の分圧は0.05Torrと見積られ
た。成長室13のなかに設置されたウェハ14は、ヒー
タ15により250℃に保たれている。導入された原料
はウェハ14」二で加熱され熱分解によりAl又はCu
を堆積させる。Also, at this time, the partial pressure of the Al source gas in the growth chamber 13 is 0.
.. The partial pressure of copper hexafluoroacetylacetonate in the growth chamber 13 was estimated to be 0.05 Torr. The wafer 14 placed in the growth chamber 13 is maintained at 250° C. by a heater 15. The introduced raw material is heated on a wafer 14'' and converted into Al or Cu by thermal decomposition.
deposit.
第2図は本発明で生成したデバイスの多層配線構造部の
断面を表したものである。図において、21は既存の配
線、22は層間絶縁膜、23.25及び27はAl薄膜
、24及び26はCu薄膜である。本実施例では、Al
1層当り0.2p mの3層とCu1層当り0.05p
mの2層の多層薄膜構造を上記の手順により形成した。FIG. 2 shows a cross section of a multilayer wiring structure of a device produced according to the present invention. In the figure, 21 is an existing wiring, 22 is an interlayer insulating film, 23, 25 and 27 are Al thin films, and 24 and 26 are Cu thin films. In this example, Al
3 layers with 0.2p m per layer and 0.05p per Cu layer
A two-layer multilayer thin film structure of m was formed by the above procedure.
これを、300°C,2時間加熱すると、AlとCuの
合金化が進み、均一なCu含有Al薄膜が形成された。When this was heated at 300°C for 2 hours, alloying of Al and Cu progressed, and a uniform Cu-containing Al thin film was formed.
このようにして形成した膜は段差被覆性に優れ、Al中
に1層程度のCuを含み、マイグレーション耐性の優れ
たものであった。The film thus formed had excellent step coverage, contained about one layer of Cu in Al, and had excellent migration resistance.
なお、本発明は以下のような変形が可能である。Note that the present invention can be modified as follows.
原料としてはジメチルアルミハイドライドに代えて、例
えばトリイソブチルアルミやジメチルアルミクロライド
やメチルアルミジクロライドなとの他の有機アルミを使
用できる。Instead of dimethylaluminum hydride, other organic aluminums such as triisobutylaluminum, dimethylaluminum dichloride, and methylaluminum dichloride can be used as raw materials.
[発明の効果1
以上のように、本発明によれば、微細なコンタクトホー
ルを埋め込むことが可能なCVD法でマイグレーション
耐性の高いAl−Cu合金薄膜を形成することができる
。[Effect 1 of the Invention As described above, according to the present invention, an Al-Cu alloy thin film with high migration resistance can be formed by a CVD method that allows filling of minute contact holes.
第1図は本発明を実施するための装置構成図、第2図は
本発明により生成される薄膜の断面構成図である。
1・水素ホンベ 2,3 バブラ容器4.5・
・温度調整器
6、7.8・マスフローコントローラ
9.10.11・・・エアーバルブ
12・バルブ開閉制御装置
13・・成長室 14・ウェハ15・・ヒー
タ 16・排気系21 既存Al配線
22・・絶縁膜23.25.27−Al薄膜
24.26・・−Cu薄膜FIG. 1 is a block diagram of an apparatus for carrying out the present invention, and FIG. 2 is a cross-sectional block diagram of a thin film produced by the present invention. 1. Hydrogen bottle 2.3 Bubbler container 4.5.
- Temperature regulator 6, 7.8 - Mass flow controller 9.10.11... Air valve 12 - Valve opening/closing control device 13 - Growth chamber 14 - Wafer 15 - Heater 16 - Exhaust system 21 Existing Al wiring
22...Insulating film 23.25.27-Al thin film 24.26...-Cu thin film
Claims (1)
キサフロロアセチルアセトナート銅(Cu(hfa)_
2を銅の原料とし、それぞれの原料ガスを混合させずに
化学気相堆積法を用いて、これら原料からAl,Cu薄
膜を交互に多層薄膜状に形成後、前記多層薄膜を加熱し
てAl−Cu合金薄膜を生成させることを特徴とするA
l−Cu合金薄膜形成方法。(1) Organic aluminum is used as a raw material for aluminum, and copper hexafluoroacetylacetonate (Cu(hfa)_
2 is used as a raw material for copper, Al and Cu thin films are alternately formed from these raw materials in the form of a multilayer thin film using chemical vapor deposition method without mixing the respective raw material gases, and then the multilayer thin film is heated to form an Al - A characterized by producing a Cu alloy thin film
Method for forming l-Cu alloy thin film.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP18207589A JPH0689452B2 (en) | 1989-07-14 | 1989-07-14 | Al-Cu alloy thin film forming method |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP18207589A JPH0689452B2 (en) | 1989-07-14 | 1989-07-14 | Al-Cu alloy thin film forming method |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH0347966A true JPH0347966A (en) | 1991-02-28 |
JPH0689452B2 JPH0689452B2 (en) | 1994-11-09 |
Family
ID=16111912
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP18207589A Expired - Lifetime JPH0689452B2 (en) | 1989-07-14 | 1989-07-14 | Al-Cu alloy thin film forming method |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0689452B2 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6089184A (en) * | 1997-06-11 | 2000-07-18 | Tokyo Electron Limited | CVD apparatus and CVD method |
US6534133B1 (en) * | 1996-06-14 | 2003-03-18 | Research Foundation Of State University Of New York | Methodology for in-situ doping of aluminum coatings |
US6696700B2 (en) * | 2001-03-09 | 2004-02-24 | National University Of Singapore | P-type transparent copper-aluminum-oxide semiconductor |
-
1989
- 1989-07-14 JP JP18207589A patent/JPH0689452B2/en not_active Expired - Lifetime
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6534133B1 (en) * | 1996-06-14 | 2003-03-18 | Research Foundation Of State University Of New York | Methodology for in-situ doping of aluminum coatings |
US6089184A (en) * | 1997-06-11 | 2000-07-18 | Tokyo Electron Limited | CVD apparatus and CVD method |
US6696700B2 (en) * | 2001-03-09 | 2004-02-24 | National University Of Singapore | P-type transparent copper-aluminum-oxide semiconductor |
Also Published As
Publication number | Publication date |
---|---|
JPH0689452B2 (en) | 1994-11-09 |
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