JPH06104901B2 - Photo CVD method - Google Patents
Photo CVD methodInfo
- Publication number
- JPH06104901B2 JPH06104901B2 JP61049616A JP4961686A JPH06104901B2 JP H06104901 B2 JPH06104901 B2 JP H06104901B2 JP 61049616 A JP61049616 A JP 61049616A JP 4961686 A JP4961686 A JP 4961686A JP H06104901 B2 JPH06104901 B2 JP H06104901B2
- Authority
- JP
- Japan
- Prior art keywords
- cvd
- film
- substrate
- irradiation
- light
- 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 - Fee Related
Links
- 238000005229 chemical vapour deposition Methods 0.000 title claims description 12
- 239000000758 substrate Substances 0.000 claims description 24
- 230000003287 optical effect Effects 0.000 claims description 8
- 239000010409 thin film Substances 0.000 claims description 6
- 238000006243 chemical reaction Methods 0.000 claims description 3
- 230000001678 irradiating effect Effects 0.000 claims description 3
- 239000010408 film Substances 0.000 description 34
- 239000000853 adhesive Substances 0.000 description 17
- 230000001070 adhesive effect Effects 0.000 description 17
- 238000000034 method Methods 0.000 description 15
- 239000007789 gas Substances 0.000 description 11
- 230000000694 effects Effects 0.000 description 6
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 4
- 229910052804 chromium Inorganic materials 0.000 description 4
- 239000011651 chromium Substances 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 230000008859 change Effects 0.000 description 3
- 238000004140 cleaning Methods 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 3
- 238000000151 deposition Methods 0.000 description 3
- 230000008021 deposition Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 2
- 229910052786 argon Inorganic materials 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 238000001182 laser chemical vapour deposition Methods 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000003795 desorption Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000031700 light absorption Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 125000002524 organometallic group Chemical group 0.000 description 1
- 238000006552 photochemical reaction Methods 0.000 description 1
- 230000001443 photoexcitation Effects 0.000 description 1
- 238000005268 plasma chemical vapour deposition Methods 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Chemical Vapour Deposition (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は光励起することにより、薄膜を形成する光CVD
方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to photo-CVD for forming a thin film by photoexcitation.
Regarding the method.
近年半導体デバイスの製造プロセスにおいては光CVDな
どのプロセス技術がプロセスの低温化、工程短縮をもた
らすものとして盛んに研究開発されている。光CVDの手
法を用いれば、従来のプラズマCVDで得られる膜と同等
の良好な膜がより低い温度で得られることが既に明らか
にされ、光CVDの手法の利点が一部明らかとなってき
た。従来の光CVD方法では一般に、CVD反応を起こす原料
ガスを基板を装着した光CVDセルに流し、その後一定強
度の光を基板上に照射して所定の膜厚になるまで光照射
を続けることにより成膜を行っていた。2. Description of the Related Art In recent years, in the manufacturing process of semiconductor devices, process technologies such as photo-CVD have been extensively researched and developed to bring about lower temperatures and shorter process steps. It has already been clarified that a good film equivalent to that obtained by conventional plasma CVD can be obtained at a lower temperature by using the optical CVD method, and some advantages of the optical CVD method have become clear. . In the conventional photo-CVD method, in general, a raw material gas that causes a CVD reaction is caused to flow through a photo-CVD cell equipped with a substrate, and then a constant intensity of light is irradiated onto the substrate to continue light irradiation until a predetermined film thickness is reached. The film was being formed.
しかしながら、一定強度の光を基板上に照射して所定の
膜厚になるまで光照射を続ける従来の光プロセス方法に
おいては、基板とCVD膜との付着強度が堆積膜の利用用
途によっては不十分で、かつその付着強度の再現性にも
問題があった。この付着力を改善し得る一方法として、
堆積膜のピーク表面温度をモニタしてこの表面温度がCV
Dプロセス中変らないよう照射光強度を抑制することに
より、CVD膜の厚み方向の膜質の均一性を向上する光CVD
方法が特願昭60-155963号に森重等により報告されてい
る。この出願の発明による方法は、照射光の吸収による
CVD膜の加熱効果が良好な膜を得る上で重要な場合に特
に有効である。また、この発明では、付着力の改善要因
として、堆積開始時の強い光照射による光洗浄効果を挙
げている。但しこの方法では、非接触かつ効率的に堆積
中のCVD膜の表面温度を測定する手段として赤外線発光
を利用しており、この場合には、CVDの領域が数μｍ程
度と微小になってくると温度の測定が極めて複雑となる
欠点がある。However, in the conventional optical process method of irradiating a constant intensity of light onto the substrate and continuing the light irradiation until a predetermined film thickness, the adhesion strength between the substrate and the CVD film is insufficient depending on the application of the deposited film. There was also a problem with the reproducibility of the adhesive strength. As one method that can improve this adhesion,
By monitoring the peak surface temperature of the deposited film, this surface temperature is CV
Optical CVD that improves the uniformity of the film quality in the thickness direction of the CVD film by suppressing the irradiation light intensity so that it does not change during the D process
The method is reported in Japanese Patent Application No. 60-155963 by Morishige et al. The method according to the invention of this application relies on the absorption of illuminating light.
It is especially effective when the heating effect of the CVD film is important for obtaining a good film. Further, in the present invention, as a factor for improving the adhesive force, the light cleaning effect by the intense light irradiation at the start of deposition is mentioned. However, in this method, infrared light emission is used as a means for measuring the surface temperature of the CVD film being deposited in a non-contact and efficient manner. In this case, the CVD region becomes as small as several μm. The disadvantage is that the measurement of temperature and temperature is extremely complicated.
本発明の目的は、以上の従来の光CVD方法の欠点を除去
し、比較的簡単な構成を用いることにより装置コストが
安く、CVD膜と基板との付着力を従来方法に比べ格段に
強くできる光CVD方法を提供することにある。The object of the present invention is to eliminate the above-mentioned drawbacks of the conventional photo-CVD method and to use a relatively simple structure, so that the apparatus cost is low, and the adhesion force between the CVD film and the substrate can be significantly stronger than the conventional method. It is to provide an optical CVD method.
本発明は光CVD方法を起こす気体中にさらされた基板上
にパルスレーザ光を繰り返し照射して、該基板上に薄膜
を形成させる光CVD方法において、２段階に照射強度を
切り換えて基板上にパルスレーザ光を照射し、後段の第
２段階では該薄膜形成に通常用いる照射強度で照射し、
前段の第１段階では、前記通常用いる照射強度よりも高
く、該薄膜の付着力増加に有効な値の強度で照射するこ
とを特徴とする光CVD方法である。The present invention is a photo-CVD method in which a pulsed laser beam is repeatedly irradiated onto a substrate exposed to a gas which causes a photo-CVD method to form a thin film on the substrate, and the irradiation intensity is switched in two steps. Irradiate with pulsed laser light, and in the second stage of the latter stage, with the irradiation intensity normally used for forming the thin film,
In the first stage of the former stage, the photo-CVD method is characterized in that the irradiation is performed at an intensity higher than the normally used irradiation intensity and effective for increasing the adhesive force of the thin film.
本発明は、照射する光の照射強度をCVD開始直後の短時
間の間、膜の堆積の起こる通常の強度よりも高い照射強
度に設定して基板に照射することにより、CVD膜の付着
力を著しく強くできるという新たな実験的知見に基ずい
て成された。本発明は光の照射強度を、第２図に示すよ
うに２段階のステップ状に制御することが特徴である。
実験においては、付着力改善効果は、第１ステップでの
光強度及びその持続時間がある値以上の場合にのみ得ら
れることがわかった。強いレーザ光照射による基板表面
の水分や有機物の脱離効果は既に知られており、この脱
離による基板表面の洗浄効果が、本発明の付着力増加の
一要因と考えられる。これに加え、第１ステップのみの
照射で得られた膜を顕微鏡で観察したところでは、明ら
かに第２ステップのみで得られる膜と外見が異なる膜が
堆積していることから、第１ステップにおいて第２ステ
ップで形成する膜と基板とを強固に結びつけるのに有効
な膜が堆積していることがわかった。なお第１ステップ
の照射強度で堆積を継続すると、膜厚の増加に伴う光の
吸収量の増加とともに膜の蒸散が起こるなどの問題を生
ずるために、良好なCVD膜を得るには本発明の２段階の
照射を行うことが有効である。The present invention sets the irradiation intensity of the irradiation light to a higher irradiation intensity than the normal intensity at which film deposition occurs for a short time immediately after the start of CVD, and then irradiates the substrate to increase the adhesion of the CVD film. It was made based on a new experimental finding that it can be made extremely strong. The present invention is characterized in that the irradiation intensity of light is controlled in two steps as shown in FIG.
In the experiment, it was found that the effect of improving the adhesive force can be obtained only when the light intensity in the first step and its duration are more than a certain value. The effect of desorbing water and organic substances on the substrate surface by intense laser light irradiation is already known, and the effect of cleaning the substrate surface by this desorption is considered to be one of the factors that increase the adhesive force of the present invention. In addition to this, when the film obtained by irradiation in only the first step is observed with a microscope, it is apparent that a film having a different appearance from the film obtained in only the second step is deposited. It was found that a film effective for firmly connecting the film formed in the second step and the substrate was deposited. When the deposition is continued at the irradiation intensity of the first step, problems such as evaporation of the film occur as the amount of absorption of light increases as the film thickness increases. Therefore, in order to obtain a good CVD film, It is effective to perform two-step irradiation.
以下図面を用いて、本発明方法の実施例を詳細に説明す
る。第１図は、本発明による具体的一実施例の構成図で
ある。この実施例は、クロムのCVDに本発明を適用した
例であり、強い付着力の堆積膜を必要とする露光用フォ
トマスクの欠陥修正などの用途に有用である。光化学反
応を生ずる原料ガスには1Torrの蒸気圧のクロムカルボ
ニル蒸気を大気圧のアルゴンガスをバッファガスと混合
して用いている。この原料ガスは、ガス供給ユニット６
よりCVDセル７に導入され、反応終了後のガスはガス処
理ユニット11で無害化処理を行う構成になっている。ま
た基板９はCVDセル７内に保持され、CVDセル７は、Ｘ−
Ｙステージ10により基板上の光照射位置を変えることが
できる構成になっている。一方ＱスイッチNd:YAGレーザ
の第４高調波システムからなる光源１からの照射光は、
可変減衰器２を通り、ミラー４で反射されたあと、レン
ズ５と窓８を通って基板９上に照射される。可変減衰器
２は制御ユニット３により光源１からの照射光強度を制
御するために用いる。この構成において、基板９への照
射光強度を、第２図に示すように第１ステップでは通常
のCVDに用いる強度I2より高いI1、第２ステップではI2
とし、また第１ステップの持続時間をT1、全反応時間を
T2であらわした時、このI1、I2、T1、T1、T2をパラメータと
して、これらの照射条件と堆積した膜の付着力との関係
を調べた。他の実験条件は以下のごとく、レーザ光の繰
り返しは2kHz、CVD面積は10μm□、基板は石英である。
I2はCVD膜の蒸散の閾値強度である3MW/cm2よりわずかに
弱い2MW/cm2に選んだ。その結果、I1が5MW/cm2以上、か
つT1が２秒以上にすると、CVD膜に、ピンセットによる
引っかき試験でなんら変化を起こさない非常に強い付着
力を付与しうることを見い出した。また、第１のステッ
プを省略すると、大幅に付着力は低下した。ただしこの
場合、CVD前の基板の洗浄の有無により付着力の弱さに
差が見られた。即ち、基板洗浄のない場合には簡単にCV
D膜が基板から剥離し、また洗浄のある場合にはピンセ
ットによる引っかき試験により部分的に膜がはがれた。
またT2を１秒から12秒まで変えて付着力を調べたが、こ
の範囲ではT2による付着力の変化はなかった。これらの
結果は、付着力改善に第１ステップでの強い照射が重要
であることをよく示している。また第２ステップの光照
射を省略して第１ステップの光強度で照射を継続する
と、一度形成された均一な厚みで滑らかな表面の薄いCV
D膜が部分的に蒸散してしまうことから、本発明の２ス
テップの照射が付着力が強くかつ表面の滑らかな良好膜
を得るために有効であることがわかる。またこの方法
は、従来の装置に照射光強度を時間的に変化させるため
の制御手段を加えるのみで実現できるので、装置価格を
低く抑えることができ、かつ膜質の再現性などの点でも
高い信頼性が得られる。Embodiments of the method of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram of a specific embodiment according to the present invention. This example is an example in which the present invention is applied to CVD of chromium, and is useful for applications such as defect correction of an exposure photomask which requires a deposited film having a strong adhesive force. Chromium carbonyl vapor having a vapor pressure of 1 Torr is used as a raw material gas for causing a photochemical reaction by mixing argon gas at atmospheric pressure with a buffer gas. This source gas is used in the gas supply unit 6
The gas introduced into the CVD cell 7 after completion of the reaction is detoxified by the gas processing unit 11. The substrate 9 is held in the CVD cell 7, and the CVD cell 7 is
The Y stage 10 is configured to change the light irradiation position on the substrate. On the other hand, the irradiation light from the light source 1 composed of the fourth harmonic system of the Q-switched Nd: YAG laser is
After passing through the variable attenuator 2 and being reflected by the mirror 4, the light is irradiated onto the substrate 9 through the lens 5 and the window 8. The variable attenuator 2 is used by the control unit 3 to control the intensity of light emitted from the light source 1. In this configuration, the irradiation light intensity of the substrate 9, higher I 1 than the intensity I 2 for use in conventional CVD in the first step as shown in FIG. 2, in the second step I 2
And the duration of the first step is T 1 , the total reaction time is
When expressed in T 2 , the relationship between these irradiation conditions and the adhesive force of the deposited film was investigated using these I 1 , I 2 , T 1 , T 1 , and T 2 as parameters. Other experimental conditions are as follows: repetition of laser light is 2 kHz, CVD area is 10 μm □ , and substrate is quartz.
I 2 was selected to be 2 MW / cm 2 which is slightly weaker than 3 MW / cm 2 which is the threshold intensity for evaporation of the CVD film. As a result, it has been found that when I 1 is 5 MW / cm 2 or more and T 1 is 2 seconds or more, a very strong adhesive force that does not cause any change in the scratch test by tweezers can be given to the CVD film. Further, when the first step was omitted, the adhesive force was significantly reduced. However, in this case, there was a difference in the weak adhesive force depending on whether or not the substrate was cleaned before CVD. That is, if there is no substrate cleaning, CV can be easily
The D film was peeled from the substrate, and when it was washed, the film was partially peeled off by a scratch test with tweezers.
Further, the adhesive force was examined by changing T 2 from 1 second to 12 seconds, but within this range, the adhesive force was not changed by T 2 . These results well indicate that strong irradiation in the first step is important for improving the adhesive force. If the second step light irradiation is omitted and the first step light intensity is continued, a CV with a uniform thickness and a smooth surface once formed is formed.
Since the D film partially evaporates, it can be seen that the two-step irradiation of the present invention is effective for obtaining a good film having a strong adhesive force and a smooth surface. Further, this method can be realized only by adding a control means for temporally changing the irradiation light intensity to the conventional apparatus, so that the apparatus price can be kept low and the film quality is highly reproducible. Sex is obtained.
以上の例ではクロムカルボニルからのクロムのレーザCV
Dの場合について述べたが、他の有機金属材料を用いた
レーザCVDにおいても成膜メカニズムの類似性から強い
付着力を得る上で本発明の２ステップの光照射が有効と
なる。また光源に関しても、レーザCVDに有効な他のエ
キシマレーザやアルゴンレーザなどの光源を用いた場合
にも本発明が適用できることは言うまでもない。In the above example, the laser CV of chromium from chromium carbonyl
Although the case of D has been described, the two-step light irradiation of the present invention is effective also in laser CVD using another organometallic material in order to obtain a strong adhesive force due to the similarity in the film formation mechanism. It is needless to say that the present invention can be applied to a light source also when another light source such as an excimer laser or an argon laser which is effective for laser CVD is used.
以上述べたように、従来の方法では、強い付着力を得る
ことが容易でなかったが、本発明の方法によれば、従来
方法によるよりも格段に強い付着力のCVD膜を形成で
き、かつプロセスの信頼性の高い優れた光CVD方法を提
供することができ、また本発明の方法を実現するための
装置構成も簡単で低価格にできる効果がある。As described above, in the conventional method, it was not easy to obtain a strong adhesive force, but according to the method of the present invention, it is possible to form a CVD film having a significantly stronger adhesive force than in the conventional method, and It is possible to provide an excellent photo-CVD method with high process reliability, and an apparatus configuration for realizing the method of the present invention is simple and inexpensive.
第１図は、本発明を適用した場合の一実施例の概略的構
成図、第２図は本発明による照射光強度の制御時間波形
を示す図である。 １……光源、２……可変減衰器、３……制御ユニット、
４……ミラー、５……レンズ、６……ガス供給ユニッ
ト、７……CVDセル、８……窓、９……基板、10……Ｘ
−Ｙステージ、11……ガス処理ユニット。FIG. 1 is a schematic configuration diagram of an embodiment to which the present invention is applied, and FIG. 2 is a diagram showing a control time waveform of irradiation light intensity according to the present invention. 1 ... Light source, 2 ... Variable attenuator, 3 ... Control unit,
4 ... Mirror, 5 ... Lens, 6 ... Gas supply unit, 7 ... CVD cell, 8 ... Window, 9 ... Substrate, 10 ... X
-Y stage, 11 ... Gas processing unit.
Claims (1)
板上にパルスレーザ光を繰返し照射して、該基板上に薄
膜を形成させる光CVD方法に於て、２段階に照射強度を
切り替えて基板上に該パルスレーザ光を照射し、後段の
第２段階では該薄膜形成に通常用いる照射強度で照射
し、前段の第１段階では、前記通常用いる照射強度より
も高く、該薄膜の付着力増加に有効な値の強度で照射す
ることを特徴とする光CVD方法。1. An optical CVD method for forming a thin film on a substrate by repeatedly irradiating the substrate exposed to a gas that causes an optical CVD reaction with a pulsed laser beam, and switching the irradiation intensity in two steps. The substrate is irradiated with the pulsed laser light, and in the second stage of the latter stage, the irradiation intensity is usually used for forming the thin film, and in the first stage of the former stage, the irradiation intensity higher than the normally used irradiation intensity is applied to the substrate. An optical CVD method characterized by irradiating with an intensity of a value effective for increasing adhesion.
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61049616A JPH06104901B2 (en) | 1986-03-07 | 1986-03-07 | Photo CVD method |
| EP86109787A EP0209131B1 (en) | 1985-07-17 | 1986-07-16 | Optical cvd method with a strong optical intensity used during an initial period and device therefor |
| DE8686109787T DE3682716D1 (en) | 1985-07-17 | 1986-07-16 | OPTICAL METHOD FOR PRODUCING LAYERS FROM THE GAS PHASE WITH A STRONG OPTICAL INTENSITY DURING THE BEGINNING PHASE, AND DEVICE THEREFOR. |
| US06/886,125 US4711790A (en) | 1985-07-17 | 1986-07-16 | Optical CVD method with a strong optical intensity used during an initial period and device therefor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61049616A JPH06104901B2 (en) | 1986-03-07 | 1986-03-07 | Photo CVD method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62207872A JPS62207872A (en) | 1987-09-12 |
| JPH06104901B2 true JPH06104901B2 (en) | 1994-12-21 |
Family
ID=12836164
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61049616A Expired - Fee Related JPH06104901B2 (en) | 1985-07-17 | 1986-03-07 | Photo CVD method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH06104901B2 (en) |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58119334A (en) * | 1982-01-08 | 1983-07-15 | Ushio Inc | Apparatus for vapor deposition by photochemical reaction |
-
1986
- 1986-03-07 JP JP61049616A patent/JPH06104901B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62207872A (en) | 1987-09-12 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |