JP2713903B2 - Dry etching method - Google Patents
Dry etching methodInfo
- Publication number
- JP2713903B2 JP2713903B2 JP62109023A JP10902387A JP2713903B2 JP 2713903 B2 JP2713903 B2 JP 2713903B2 JP 62109023 A JP62109023 A JP 62109023A JP 10902387 A JP10902387 A JP 10902387A JP 2713903 B2 JP2713903 B2 JP 2713903B2
- Authority
- JP
- Japan
- Prior art keywords
- etching
- substrate
- temperature
- gas
- workpiece
- 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.)
- Expired - Lifetime
Links
Landscapes
- Drying Of Semiconductors (AREA)
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明はエッチング方法に係り、特にエッチング残渣
が生ずるものに好適なエッチング方法に関するものであ
る。
〔従来の技術〕
従来のエッチング方法は、例えば、ソリッド・ステイ
ツ・テクノロジー，第25巻，第８号（1982−８）第84頁
から第87頁（Solid State Technology,Vol.25,No.8,PP8
4−87）で示されているように、水冷された載置台と該
載置台に載置された基板との間に圧力6Torr程度のHeガ
スを流通させ、載置台と基板との間の熱抵抗を減少させ
て基板を効果的に冷却し、エッチングを行うものがあっ
た。
また、特開昭59−76876号に示されているように、被
エッチング板を高温で処理した後、低温でオーバーエッ
チングして、被エッチング材とレジストとのエッチング
選択比，生産性を向上させるものがあった。
〔発明が解決しようとする問題点〕
上記従来技術は、被処理物としてAl−Si−Cu膜等のエ
ッチング残渣を生じやすいものについて配慮されておら
ず、Al−Si−Cu膜のエッチングではCu成分がAlやSiに比
べてラジカル反応に乏しいため、エッチング残渣が生じ
てしばしば問題となる。Cu成分の除去速度は温度依存性
があるが、レジストマスクの耐スパッタ性や耐熱性の問
題であまり温度を上げることができず、許容範囲内でエ
ッチングされるのでCu成分の残渣が生じる。
一方、Al−Si−Cu膜のエッチングが終了したのち、い
わゆるオーバエッチング（一部のエッチング残りや残渣
の除去を行うための追加エッチング処理）を行うが、こ
のとき下地膜（例えばSiO2膜やSi膜等）との選択比の向
上や素子ダメージの低減のために、エッチング形状に影
響を与えない範囲で電力（例えば高周波電力）を小さく
してエッチング処理を行う場合がある。この場合、被処
理物への入熱は電力の低減によって減少し、被処理物の
温度が低減し、Cu成分の除去能力が低下するという問題
があった。
本発明の目的は、エッチング残渣を生じやすいものに
ついて、低ダメージで残渣を容易に除去することのでき
るドライエッチング方法を提供することにある。
〔問題点を解決するための手段〕
上記目的は、被処理物と該被処理物を配置する冷却さ
れた載置台との間に冷却ガスを供給し、減圧排気された
真空容器内で反応性ガスのプラズマを用いて被処理物を
ドライエッチングする際、エッチング終点検出後のオー
バーエッチング時にプラズマ発生用の高周波電力をエッ
チング時より下げるとともに、被処理物と載置台との間
の冷却ガスの熱伝達抵抗を大きくするように冷却ガスの
圧力をエッチング時より下げることにより、達成され
る。
〔作用〕
被処理物のエッチングステップが変わった時点、例え
ば、オーバエッチングを行うときに、被処理物と載置台
との間に供給する冷却用ガスの圧力を変える、例えば、
圧力を下げることにより、冷却用ガスを介して被処理物
から載置台へ逃げる熱量が少なくなり、被処理物の温度
が上昇し、残渣していたものが容易に除去できる。
〔実 施 例〕
以下、本発明の一実施例を第１図および第２図により
説明する。
第１図は、本発明を実施するためのドライエッチング
装置の一例を示すものである。真空処理室１の下部には
絶縁体６を介して下部電極３が設けてあり、下部電極３
に対向し放電空間９を有して上部電極２が真空処理室１
の上部に取り付けてある。下部電極３にはマッチングボ
ックス４を介して、プラズマ発生用の電源、この場合
は、高周波電源５が接続してあり、高周波電源５の他方
および真空処理室１は接地してある。また、真空処理室
１の下部には排気用導管10を介して真空ポンプ11がつな
げてあり、上部電極２には図示しない流量制御器を介し
て図示しない処理ガス供給源がつなげてある。
下部電極３の上面には図示しない搬送装置で真空処理
室１内に搬入された被処理物である基板７が載置され、
基板押え８で基板周囲を押え付けて支持される。
下部電極３の上部で基板７の裏面部には溝20が形成さ
れ、さらに下部電極３には溝20と下部電極３の下面とを
連通させる供給路19が形成してあり、供給路19には導管
18が接続され、導管18は流量調節器17を介して冷却用ガ
ス、例えば、Heガスの供給源につなげてある。導管18に
は圧力検知器21が設けてあり、圧力検知器21の出力信号
は制御装置22に入力され、制御装置22の出力信号は流量
調節器17に入力される。
また、下部電極３の溝20下部には冷媒流路14が形成し
てあり、冷媒流路14には冷媒供給路13および冷媒排出路
15が設けてある。冷媒供給路13には導管12が接続してあ
り、導管12は冷媒、この場合、冷却水の供給源につなが
れている。冷媒排出路15には導管16が接続してあり、冷
却後の冷却水が排出される。
上記構成の装置により、基板７を搬送装置によって真
空処理室１内に搬入し、下部電極３上に載置する。その
後、基板押え８によって基板７を下部電極３上面に圧着
する。基板７の配置が完了すると、処理ガスが、この場
合、上部電極２を介して放電空間９部に供給され、真空
ポンプ11で真空処理室１内を所定圧力に減圧排気し、こ
れとともに高周波電源５によって下部電極３に高周波電
力を印加して放電空間９にグロー放電を生じさせ、処理
ガスのプラズマを生成させて基板７をエッチング処理す
る。
エッチングが開始されると、溝20に流量調節器17によ
って流量調整されたHeガスを供給し、基板７から下部電
極３に伝わる熱を伝えやすくする。このとき、下部電極
３は冷却流路14に流された冷却水によって冷却してあ
る。
こうして基板７を冷却し、最適な基板温度でエッチン
グを行っていき、エッチングが終了すると冷却用ガスで
あるHeガスの供給，処理ガスの供給および高周波電力の
印加を停止し、その後基板７を真空処理室１内から搬出
する。
ここで、基板７が、例えば、Al−Si−Cu膜を有したも
のであり、このAl−Si−Cu膜をエッチングするものであ
る場合には、このエッチング処理中において冷却用ガス
であるHeガスが次のように制御され、エッチング処理さ
れていく。
まず最初は、レジストマスクに悪影響を及ぼさないよ
うに、基板７の温度をレジストマスクの許容範囲内の温
度に調整しエッチングを行う。この温度調整は、あらか
じめエッチング処理データとしてHeガスの圧力値と基板
７の温度値との関係を制御装置22に記憶させておき、圧
力検知器21によってHeガスの圧力値を測定し制御装置22
に入力して、所定の基板温度になるHeガスの圧力値にな
るように流量調節器17を制御装置22によって制御して行
なう。
次に、第２図に示すようにある程度高い圧力のHeガス
を供給して所定の基板温度でエッチングされるAl−Si−
Cu膜のエッチングがほぼ完了し、オーバエッチングが始
まる時間t1からは選択比の向上や素子ダメージの低減の
ために高周波電力を下げてエッチングを行う。これによ
り、Heガスの圧力がそのままだと基板温度は下がるた
め、逆にHeガスの圧力を下げ基板７と下部電極３との間
の熱伝達抵抗を大きくして、基板７が冷却され過ぎるの
を防止し、基板温度をエッチング残渣物、この場合は、
Cu成分が除去可能な温度に維持して、時間t1からt2間オ
ーバエッチングする。なお、オーバエッチングに際して
は、所定のエッチングは基本的に終了しているので、多
少基板温度が高くなってレジストマスクの耐熱域を越え
ても問題ない。
以上、本一実施例によれば、オーバエッチング時に冷
却ガスの圧力を下げることにより、基板温度を上げるこ
とができるので、エッチング残渣を容易に除去すること
ができるという効果がある。また、これにより、エッチ
ング処理の生産性を向上させることができる。
なお、本一実施例ではAl−Si−Cu膜のエッチングにつ
いて述べたが、被処理物が多層構造となっている場合や
レジスト，被エッチング材および下地膜の相互間でエッ
チング処理に温度依存性がある場合に、基板温度を制御
してエッチングするのに有効である。
また、本一実施例では平行平板型電極のドライエッチ
ング装置について述べたが、プラズマ発生手段が別に設
けられ、基板の載置台にエッチングの制御用の電源のみ
が接続されたドライエッチング装置でも良い。
さらに、本一実施例の下地電極３に温度検知器を設け
て、制御装置22に下部電極３の温度を入力し、基板温度
と冷却ガス圧力との関係を補正するようにしておけば、
冷却水の温度が変わっても基板温度を所定の温度に制御
できる。
〔発明の効果〕
本発明によれば、エッチング残渣を生じやすいものに
ついて、残渣を容易に除去することができるという効果
がある。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an etching method, and more particularly to an etching method suitable for an etching residue. [Prior Art] A conventional etching method is described in, for example, Solid States Technology, Vol. 25, No. 8, (1982-8), pp. 84 to 87 (Solid State Technology, Vol. 25, No. 8). , PP8
As shown in 4-87), He gas at a pressure of about 6 Torr is passed between the water-cooled mounting table and the substrate mounted on the mounting table, and the heat between the mounting table and the substrate is heated. In some cases, the resistance is reduced to effectively cool the substrate and perform etching. Further, as disclosed in JP-A-59-76876, after a plate to be etched is processed at a high temperature, it is over-etched at a low temperature to improve the etching selectivity between the material to be etched and the resist and the productivity. There was something. [Problems to be Solved by the Invention] The above-mentioned prior art does not consider an object to be processed that easily generates an etching residue such as an Al-Si-Cu film. Since the component is poor in radical reaction as compared with Al and Si, an etching residue often occurs, which is a problem. Although the removal rate of the Cu component has a temperature dependency, the temperature cannot be raised so much due to the problem of the sputter resistance and heat resistance of the resist mask, and the etching is performed within an allowable range, so that a residue of the Cu component is generated. Meanwhile, after the etching of the Al-Si-Cu film is completed, performs the so-called over-etching (additional etching process for the removal of a portion of the etching residue or residues), this time the base film (e.g., SiO 2 film Ya In order to improve the selectivity with respect to a Si film or the like and to reduce device damage, etching may be performed by reducing power (for example, high-frequency power) within a range that does not affect the etching shape. In this case, there has been a problem that the heat input to the object to be processed is reduced due to the reduction in electric power, the temperature of the object to be processed is reduced, and the ability to remove the Cu component is reduced. An object of the present invention is to provide a dry etching method that can easily remove an etching residue with low damage and easily remove the residue. [Means for Solving the Problems] The object of the present invention is to supply a cooling gas between an object to be processed and a cooled mounting table on which the object is disposed, and to provide a reactive gas in a vacuum vessel evacuated and evacuated. When dry-etching an object using gas plasma, the high-frequency power for plasma generation is reduced during over-etching after the end point of the etching is detected, and the heat of the cooling gas between the object and the mounting table is reduced. This is achieved by lowering the pressure of the cooling gas from the time of etching so as to increase the transmission resistance. [Operation] When the etching step of the object to be processed is changed, for example, when performing over-etching, the pressure of the cooling gas supplied between the object to be processed and the mounting table is changed, for example,
By reducing the pressure, the amount of heat escaping from the processing object to the mounting table via the cooling gas decreases, the temperature of the processing object increases, and the residue can be easily removed. [Embodiment] An embodiment of the present invention will be described below with reference to Figs. FIG. 1 shows an example of a dry etching apparatus for carrying out the present invention. A lower electrode 3 is provided below the vacuum processing chamber 1 with an insulator 6 interposed therebetween.
The upper electrode 2 has a discharge space 9 facing the
It is attached to the upper part of. A power supply for plasma generation, in this case, a high-frequency power supply 5 is connected to the lower electrode 3 via a matching box 4, and the other of the high-frequency power supply 5 and the vacuum processing chamber 1 are grounded. A vacuum pump 11 is connected to a lower portion of the vacuum processing chamber 1 via an exhaust pipe 10, and a processing gas supply source (not shown) is connected to the upper electrode 2 via a flow controller (not shown). On the upper surface of the lower electrode 3, a substrate 7 which is a processing object carried into the vacuum processing chamber 1 by a transfer device (not shown) is placed.
The periphery of the substrate is pressed and supported by the substrate presser 8. A groove 20 is formed on the lower surface of the substrate 7 above the lower electrode 3, and a supply path 19 is formed in the lower electrode 3 for communicating the groove 20 with the lower surface of the lower electrode 3. Is a conduit
A conduit 18 is connected, and the conduit 18 is connected via a flow controller 17 to a supply source of a cooling gas, for example, He gas. A pressure detector 21 is provided in the conduit 18, and an output signal of the pressure detector 21 is input to the control device 22, and an output signal of the control device 22 is input to the flow rate controller 17. A coolant passage 14 is formed below the groove 20 of the lower electrode 3, and the coolant passage 14 has a coolant supply passage 13 and a coolant discharge passage.
15 are provided. A conduit 12 is connected to the refrigerant supply passage 13, and the conduit 12 is connected to a supply source of a refrigerant, in this case, cooling water. A conduit 16 is connected to the refrigerant discharge path 15, and the cooling water after cooling is discharged. With the apparatus having the above configuration, the substrate 7 is carried into the vacuum processing chamber 1 by the transfer device, and is placed on the lower electrode 3. Thereafter, the substrate 7 is pressed against the upper surface of the lower electrode 3 by the substrate holder 8. When the disposition of the substrate 7 is completed, the processing gas is supplied to the discharge space 9 via the upper electrode 2 in this case, and the inside of the vacuum processing chamber 1 is evacuated to a predetermined pressure by the vacuum pump 11, and the high frequency power supply The high frequency power is applied to the lower electrode 3 by 5 to generate a glow discharge in the discharge space 9 to generate plasma of a processing gas to etch the substrate 7. When the etching is started, He gas whose flow rate is adjusted by the flow rate adjuster 17 is supplied to the groove 20 so that heat transmitted from the substrate 7 to the lower electrode 3 is easily transmitted. At this time, the lower electrode 3 has been cooled by the cooling water flowing through the cooling channel 14. In this way, the substrate 7 is cooled, etching is performed at an optimum substrate temperature, and when the etching is completed, the supply of the He gas as a cooling gas, the supply of the processing gas, and the application of the high frequency power are stopped. It is unloaded from the processing chamber 1. Here, when the substrate 7 has, for example, an Al-Si-Cu film and is to etch the Al-Si-Cu film, He, which is a cooling gas during the etching process, is used. The gas is controlled and etched as follows. First, etching is performed by adjusting the temperature of the substrate 7 to a temperature within the allowable range of the resist mask so as not to adversely affect the resist mask. In this temperature adjustment, the relationship between the pressure value of He gas and the temperature value of the substrate 7 is stored in advance in the control device 22 as etching process data, and the pressure value of the He gas is measured by the pressure detector 21 to control the control device 22.
And the flow controller 17 is controlled by the control device 22 so that the pressure value of the He gas reaches a predetermined substrate temperature. Next, as shown in FIG. 2, He gas at a relatively high pressure is supplied to etch the Al-Si-
Etching the Cu film is almost completed, etching is performed by lowering the RF power in order to reduce the increase or element damage selectivity ratio from time t 1 overetching begins. As a result, if the pressure of the He gas remains unchanged, the substrate temperature decreases. Conversely, the pressure of the He gas is lowered to increase the heat transfer resistance between the substrate 7 and the lower electrode 3, and the substrate 7 is excessively cooled. To prevent the substrate temperature from etching residue, in this case,
And Cu components are maintained in removable temperature, overetching between t 2 from time t 1. In the over-etching, since the predetermined etching is basically completed, there is no problem even if the substrate temperature is slightly increased and exceeds the heat-resistant range of the resist mask. As described above, according to the present embodiment, the substrate temperature can be increased by lowering the pressure of the cooling gas at the time of over-etching, so that the etching residue can be easily removed. In addition, thereby, the productivity of the etching process can be improved. In this embodiment, the etching of the Al-Si-Cu film has been described. However, when the object to be processed has a multi-layer structure, the temperature dependence of the etching process between the resist, the material to be etched and the base film is different. In some cases, it is effective to control the substrate temperature to perform etching. Further, in this embodiment, the dry etching apparatus of the parallel plate type electrode has been described. However, a dry etching apparatus in which a plasma generating means is separately provided and only a power supply for controlling the etching is connected to the mounting table of the substrate may be used. Furthermore, if a temperature detector is provided for the base electrode 3 of the present embodiment, the temperature of the lower electrode 3 is input to the control device 22, and the relationship between the substrate temperature and the cooling gas pressure is corrected.
Even if the temperature of the cooling water changes, the substrate temperature can be controlled to a predetermined temperature. [Effects of the Invention] According to the present invention, there is an effect that the residue can be easily removed from the etching residue which is likely to be generated.
【図面の簡単な説明】
第１図は本発明の一実施例であるドライエッチング方法
を実施するための装置の構成を示す図、第２図は冷却用
ガスの制御の一例を示す図である。
１……真空処理室、３……下部電極、７……基板、14…
…冷媒流路、17……流量調節器、20……溝、21……圧力
検知器、22……制御装置BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing a configuration of an apparatus for performing a dry etching method according to an embodiment of the present invention, and FIG. 2 is a diagram showing an example of control of a cooling gas. . 1 ... vacuum processing chamber, 3 ... lower electrode, 7 ... substrate, 14 ...
... refrigerant channel, 17 ... flow regulator, 20 ... groove, 21 ... pressure detector, 22 ... control device
───────────────────────────────────────────────────── フロントページの続き (72)発明者 工藤 勝義 下松市大字東豊井794番地 株式会社日 立製作所笠戸工場内 (56)参考文献 特開 昭59−159984（ＪＰ，Ａ) 特開 昭60−115226（ＪＰ，Ａ) 特開 昭60−154529（ＪＰ，Ａ) ────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Katsuyoshi Kudo Kudamatsu City 794 Higashi Toyoi Sun Inside the Kasado Factory (56) References JP-A-59-159984 (JP, A) JP-A-60-115226 (JP, A) JP-A-60-154529 (JP, A)
Claims (1)
との間に冷却ガスを供給し、減圧排気された真空容器内
で反応性ガスのプラズマを用いて前記被処理物をドライ
エッチングする方法において、前記被処理物のエッチン
グ終点検出後のオーバーエッチング時にプラズマ発生用
の高周波電力を前記エッチング時より下げるとともに、
前記被処理物と前記載置台との間の冷却ガスの熱伝達抵
抗を大きくするよう前記冷却ガスの圧力を前記エッチン
グ時より下げて制御し、前記被処理物の温度をエッチン
グ残渣を除去可能な温度に維持することを特徴とするド
ライエッチング方法。(57) [Claims] A cooling gas is supplied between the workpiece and a cooled mounting table on which the workpiece is placed, and the workpiece is dry-etched using a plasma of a reactive gas in a vacuum vessel evacuated and evacuated. In the method, while lowering the high-frequency power for plasma generation during the over-etching after the etching end point detection of the object to be processed than during the etching,
The pressure of the cooling gas is controlled to be lower than at the time of the etching so as to increase the heat transfer resistance of the cooling gas between the workpiece and the mounting table, and the temperature of the workpiece can be removed from the etching residue. A dry etching method characterized by maintaining the temperature.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62109023A JP2713903B2 (en) | 1987-05-06 | 1987-05-06 | Dry etching method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62109023A JP2713903B2 (en) | 1987-05-06 | 1987-05-06 | Dry etching method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63274147A JPS63274147A (en) | 1988-11-11 |
| JP2713903B2 true JP2713903B2 (en) | 1998-02-16 |
Family
ID=14499638
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62109023A Expired - Lifetime JP2713903B2 (en) | 1987-05-06 | 1987-05-06 | Dry etching method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2713903B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02210826A (en) * | 1989-02-10 | 1990-08-22 | Hitachi Ltd | Plasma etching method and equipment |
| JP2923218B2 (en) * | 1995-01-30 | 1999-07-26 | 株式会社日立製作所 | Sample processing method |
| JP4694249B2 (en) * | 2005-04-20 | 2011-06-08 | 株式会社日立ハイテクノロジーズ | Vacuum processing apparatus and sample vacuum processing method |
| JP5550883B2 (en) * | 2009-11-05 | 2014-07-16 | 株式会社アルバック | MEMS device manufacturing method and MEMS device manufacturing apparatus |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59159984A (en) * | 1983-03-03 | 1984-09-10 | Matsushita Electric Ind Co Ltd | Dry etching device |
| JPH0622213B2 (en) * | 1983-11-28 | 1994-03-23 | 株式会社日立製作所 | Sample temperature control method and apparatus |
| JPS60154529A (en) * | 1984-01-23 | 1985-08-14 | Mitsubishi Electric Corp | Dry etching device |
-
1987
- 1987-05-06 JP JP62109023A patent/JP2713903B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63274147A (en) | 1988-11-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3426040B2 (en) | Plasma etching apparatus with heated scavenging surface | |
| US5248370A (en) | Apparatus for heating and cooling semiconductor wafers in semiconductor wafer processing equipment | |
| EP0397315B1 (en) | Method and apparatus for heating and cooling semiconductor wafers in semiconductor wafer processing equipment | |
| JP4716566B2 (en) | Plasma processing chamber for reducing copper oxide on a substrate and method thereof | |
| JP4256064B2 (en) | Control method of plasma processing apparatus | |
| JP2713903B2 (en) | Dry etching method | |
| US6787475B2 (en) | Flash step preparatory to dielectric etch | |
| JPH07221076A (en) | Etching method and apparatus used for it | |
| JPH05267249A (en) | Dry etching method and dry etching apparatus | |
| JP3218917B2 (en) | Plasma processing apparatus and plasma processing method | |
| JP3180438B2 (en) | Plasma processing device substrate fixing method | |
| JPH10116822A (en) | Method and device for dry-etching | |
| JPH0691037B2 (en) | Dry etching method and device | |
| JP3020621B2 (en) | Plasma etching method | |
| JP3093445B2 (en) | Plasma etching method | |
| JP3150044B2 (en) | Plasma processing apparatus and control method thereof | |
| JPH05275376A (en) | Dry-etching device and dry-etching method | |
| JPH07176520A (en) | Semiconductor manufacturing device | |
| JPH0334540A (en) | Plasma treatment apparatus and temperature control of wafer in this apparatus | |
| US20220238315A1 (en) | Substrate processing method, component processing method, and substrate processing apparatus | |
| JP3397917B2 (en) | Plasma etching method | |
| JP3303651B2 (en) | Dry etching method | |
| US5916411A (en) | Dry etching system | |
| JPS6329504A (en) | Bias sputtering | |
| JPH0323633A (en) | Dry etching |