JPH01179908A - Method for uniformizing intensity distribution of laser beam - Google Patents
Method for uniformizing intensity distribution of laser beamInfo
- Publication number
- JPH01179908A JPH01179908A JP63002622A JP262288A JPH01179908A JP H01179908 A JPH01179908 A JP H01179908A JP 63002622 A JP63002622 A JP 63002622A JP 262288 A JP262288 A JP 262288A JP H01179908 A JPH01179908 A JP H01179908A
- Authority
- JP
- Japan
- Prior art keywords
- interference fringe
- intensity distribution
- laser
- pulse
- uniformizing
- 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
- 238000009826 distribution Methods 0.000 title claims abstract description 24
- 238000000034 method Methods 0.000 title claims description 23
- 230000001427 coherent effect Effects 0.000 abstract description 3
- 239000000758 substrate Substances 0.000 description 12
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 9
- 238000010586 diagram Methods 0.000 description 9
- 229910052710 silicon Inorganic materials 0.000 description 9
- 239000010703 silicon Substances 0.000 description 9
- 230000000694 effects Effects 0.000 description 3
- PZPGRFITIJYNEJ-UHFFFAOYSA-N disilane Chemical compound [SiH3][SiH3] PZPGRFITIJYNEJ-UHFFFAOYSA-N 0.000 description 2
- 229910007264 Si2H6 Inorganic materials 0.000 description 1
- ISQINHMJILFLAQ-UHFFFAOYSA-N argon hydrofluoride Chemical compound F.[Ar] ISQINHMJILFLAQ-UHFFFAOYSA-N 0.000 description 1
- 241001233037 catfish Species 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000001678 irradiating effect Effects 0.000 description 1
- 238000001182 laser chemical vapour deposition Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 238000006303 photolysis reaction Methods 0.000 description 1
- 230000015843 photosynthesis, light reaction Effects 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 238000007740 vapor deposition Methods 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔概要〕
インテグレータレンズを用いて光強度分布を均一化する
際に、照射面でのビーム位置またはこのレンズを往復運
動させて、スペックルノイズの発生を防止することによ
るレーザビームの強度分布を均一化する方法に関し、
インテグレータレンズを用いるレーザ光の出力光の強度
分布を均一化する方法において、従来のスペックルノイ
ズの発生を防止する方法を提供することを目的とし、
インテグレータレンズを用いてレーザ光の光強度分布を
均一化する方法において、試料の照射面上でのビーム位
置を干渉縞間隔の１／２以上または干渉縞間隔の整数倍
の範囲で往復移動させることを特徴とするレーザビーム
の強度分布を均一化する方法を含み構成する。[Detailed Description of the Invention] [Summary] When uniformizing the light intensity distribution using an integrator lens, the generation of speckle noise is prevented by reciprocating the beam position on the irradiation surface or this lens. Regarding a method of uniformizing the intensity distribution of a laser beam, the purpose of this invention is to provide a method of preventing the generation of conventional speckle noise in a method of uniformizing the intensity distribution of the output light of a laser beam using an integrator lens, In a method of uniformizing the light intensity distribution of laser light using an integrator lens, the beam position on the irradiation surface of the sample is moved back and forth within a range of 1/2 or more of the interference fringe interval or an integral multiple of the interference fringe interval. The present invention includes a method for uniformizing the intensity distribution of a laser beam, characterized by:
（産業上の利用分野〕
本発明は、インテグレータレンズを用いて光強度分布を
均一化する際に、照射面でのビーム位置またはこのレン
ズを往復運動させて、スペックルノイズの発生を防止す
ることによるレーザビームの強度分布を均一化する方法
に関する。(Industrial Application Field) The present invention is directed to preventing the generation of speckle noise by reciprocating the beam position on the irradiation surface or the lens when uniformizing the light intensity distribution using an integrator lens. This invention relates to a method for uniformizing the intensity distribution of a laser beam.
例えば基板上にシリコン（Ｓｉ）を成膜する技術、すな
わちジシラン（Ｓｉ２）Ｉｓ ）をエキシマレーザ（Ａ
ｒＦ ＋アルゴンフロライド： １９３ ｎｍ）のレー
ザによって光分解してシリコンを基板上に成長させるレ
ーザ気相成長（ＣＶＤ ）法が知られている。このよう
なレーザＣＶＤ法では、出力光の強度分布を均一化する
ことが求められる。第３図はエキシマレーザ出力光の強
度分布図で、横軸にビー ム幅、縦軸に出力光の強度を
とるが、実際に得られる出力分布は線ＡまたはＢに示す
如くビーム幅全体にわたって不均一な強度分布を示す。For example, a technique for depositing silicon (Si) on a substrate, i.e. disilane (Si2)Is), is used with an excimer laser (A
A laser vapor deposition (CVD) method is known in which silicon is grown on a substrate by photolysis using a rF + argon fluoride (193 nm) laser. In such a laser CVD method, it is required to make the intensity distribution of output light uniform. Figure 3 is a diagram showing the intensity distribution of excimer laser output light, with the horizontal axis representing the beam width and the vertical axis representing the intensity of the output light.Actually, the output distribution obtained is over the entire beam width, as shown by line A or B. Shows non-uniform intensity distribution.
第４図を参照すると、レーザ光２１は基板２２に対して
垂直方向に照射され、他方基板２２に対してはＳｉ １
１６が吹き付けられ、基板の上でＳｉ２Ｈ６がレーザ光
によって分解してシリコンが基板２２上に堆積するので
あるが、レーザ光２１が基板２２に照射したときに、基
板２２上には例えば第３図に示した強度の不均一性に対
応した干渉縞２３が第５図に示される如くに作られる。Referring to FIG. 4, the laser beam 21 is irradiated perpendicularly to the substrate 22, and the Si 1
16 is sprayed onto the substrate, Si2H6 is decomposed by the laser beam on the substrate, and silicon is deposited on the substrate 22. When the substrate 22 is irradiated with the laser beam 21, for example, as shown in FIG. Interference fringes 23 corresponding to the non-uniformity of intensity shown in FIG. 5 are created as shown in FIG.
そうなると、基板２２上に成長したシリコン膜２４を断
面で示す第６図を参照すると、干渉縞間隔に対応して不
均一な凹凸をもったシリコン膜２４が形成される。これ
は、レーザ光の強度がシリコンの成長レート（速度）に
影響するからである。そこで、シリコン膜２４が均一に
成長するように、第３図に点線Ｃで示す如き出力光の均
一な強度分布を得ることが求められる。In this case, referring to FIG. 6, which shows a cross section of the silicon film 24 grown on the substrate 22, the silicon film 24 is formed with non-uniform irregularities corresponding to the interference fringe spacing. This is because the intensity of the laser light affects the growth rate of silicon. Therefore, in order to uniformly grow the silicon film 24, it is required to obtain a uniform intensity distribution of the output light as shown by the dotted line C in FIG.
しかし、レーザ装置の動作状態を制御してその出力光の
強度分布を均一化することはきわめて難しい。このため
、通常は出力光を光学的な手段により均一化する方法が
用いられ、その一つにインテグレータレンズを用いる方
法がある。第７図はインテグレータレンズを説明するた
めの図で、図中、３１はインテグレータレンズ、３２は
入射するレーザビーム、３３は出射するレーザビーム、
ＸとＸｏはそれぞれ入射、出射するレーザビームの拡が
り、ｙとｙ′それぞれ入射、出射するレーザビームの強
度（任意単位）を示す。この方法では、レーザビームを
分割して投影し、重ね合せて均一化するため、コヒーレ
ントなレーザ光の場合には、分割されたレーザ光の干渉
によってスペックルノイズを発生させる問題がある。However, it is extremely difficult to control the operating state of a laser device to make the intensity distribution of its output light uniform. For this reason, a method is usually used in which the output light is made uniform by optical means, one of which is a method using an integrator lens. FIG. 7 is a diagram for explaining the integrator lens, in which 31 is an integrator lens, 32 is an incident laser beam, 33 is an output laser beam,
X and Xo represent the spread of the incident and emitted laser beams, respectively, and y and y' represent the intensities (arbitrary units) of the incident and emitted laser beams, respectively. In this method, the laser beams are divided, projected, and superimposed to make them uniform. Therefore, in the case of coherent laser beams, there is a problem in that speckle noise is generated due to interference between the divided laser beams.
そこで本発明は、インテグレータレンズを用いるレーザ
光の出力光の強度分布を均一化する方法において、従来
のスペックルノイズの発生を防止する方法を提供するこ
とを目的とする。SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a method of preventing the generation of speckle noise in a method of uniformizing the intensity distribution of output light of a laser beam using an integrator lens.
上記問題点は、インテグレータレンズを用いてレーザ光
の光強度分布を均一化する方法において、試料の照射面
上でのビーム位置を干渉縞間隔の１／２以上または干渉
縞間隔の整数倍の範囲で往復移動させることを特徴とす
るレーザビームの強度分布を均一化する方法によって解
決される。The above problem is that in the method of making the light intensity distribution of laser light uniform using an integrator lens, the beam position on the irradiated surface of the sample is set to a range of 1/2 or more of the interference fringe interval or an integral multiple of the interference fringe interval. This problem is solved by a method of uniformizing the intensity distribution of a laser beam, which is characterized by moving the laser beam back and forth.
スペックルノイズとは干渉縞である。この縞の間隔は数
μ糟以下のオーダのものである。したがって、本発明で
は照射面上でのビーム位置を干渉縞間隔の１／２以上ま
たは整数倍の範囲で往復移動させることによってスペッ
クルノイズの発生を防止した。また他の方法では、イン
チグレータレ、ンズを往復運動させて干渉縞の強弱部の
位置を変えてスペックルノイズの発生を防止した。Speckle noise is interference fringes. The spacing between these stripes is on the order of several micrometers or less. Therefore, in the present invention, the generation of speckle noise is prevented by reciprocating the beam position on the irradiation surface within a range of 1/2 or more or an integral multiple of the interference fringe interval. In another method, speckle noise was prevented by reciprocating the inch gray lens to change the positions of the strong and weak parts of the interference fringes.
以下、本発明を図示の実施例により具体的に説明する。 Hereinafter, the present invention will be specifically explained with reference to illustrated embodiments.
第１図は本発明実施例の図で、同図（ａ）に示される例
では、照射面上でのビーム位置を干渉縞間隔の半分以上
の範囲で往復移動させる。第１図（ａ）において、１１
はパルスレーザ光、１２はインテグレータレンズ、１３
は試料（例えば基板）を示し、この例では、試料１３を
矢印の示す如くに往復運動させることにより、試料面上
でのビーム位置を往復移動させるものである。FIG. 1 is a diagram of an embodiment of the present invention. In the example shown in FIG. 1(a), the beam position on the irradiation surface is reciprocated within a range of more than half the interference fringe interval. In FIG. 1(a), 11
is a pulsed laser beam, 12 is an integrator lens, 13 is
indicates a sample (for example, a substrate), and in this example, by reciprocating the sample 13 as indicated by the arrow, the beam position on the sample surface is reciprocated.
第１図ｔｂ＞に示す例では、インテグレータレンズ１２
そのものを矢印の示す如くに往復運動させることによっ
て試料１３上でのビーム位置を干渉縞間隔の半分以上の
範囲で往復移動させるのである。In the example shown in FIG. 1tb>, the integrator lens 12
By reciprocating the beam as shown by the arrow, the beam position on the sample 13 is reciprocated within a range of more than half the interference fringe interval.
試料１３またはインテグレータレンズ１２を往復運動さ
せる際の振幅は、干渉縞間隔の１／２以上とする。この
移動速度は、パルスからパルスへの時間に干渉縞間隔の
１／２以下の長さを移動する程度のものとする。具体例
として、干渉縞間隔は０．２μ−とし、繰返し数１００
Ｈｚでパルスレーザ光を照射したとき、使用したレーザ
のパルス幅は１５ｎｓであるる、１シヨツト毎の照射は
移動部を停止した状態で行った。すなわち、
振幅：０．１．１７１１
移動速度： ０．１ ／ （１／１００ ’）”’ １
０ＩＪｒａ ／ ｓｅｃ
とした。このような移動は、圧電素子を用いて実行した
。The amplitude when reciprocating the sample 13 or the integrator lens 12 is set to be 1/2 or more of the interference fringe spacing. This moving speed is such that the length of the interference fringe interval is less than 1/2 in the time from pulse to pulse. As a specific example, the interference fringe spacing is 0.2 μ-, and the number of repetitions is 100.
When irradiating with pulsed laser light at Hz, the pulse width of the laser used was 15 ns, and each shot was irradiated with the moving part stopped. That is, Amplitude: 0.1.1711 Traveling speed: 0.1 / (1/100')"' 1
0IJra/sec. Such movement was performed using piezoelectric elements.
第２図（ａｌと山）は本発明実施例の概略図で、図中、
１１ａはレーザ光源で、同図（ａ）の例では光源１１ａ
からのレーザ光１１をインテグレータレンズ１２に通し
、次いでチャンバ１４の窓を通してステージ１６上の試
料１３に照射するが、ステージ１６は、１対の同期せし
められる圧電素子１７．１７によって前記した如くに移
動する。FIG. 2 (al and mountains) is a schematic diagram of an embodiment of the present invention, and in the figure,
11a is a laser light source, and in the example shown in FIG.
The laser beam 11 from the laser is passed through the integrator lens 12 and then through the window of the chamber 14 to irradiate the sample 13 on the stage 16, which is moved as described above by a pair of synchronized piezoelectric elements 17.17. do.
同図（ｂｌには、インテグレータレンズ１２を移動させ
る例を示し、同レンズ１２は一方側で圧電素子１７に連
結され、他方側では固定されたばね１８に連結され、圧
電素子はパルス発振器１９に接続されている。The figure (bl) shows an example of moving the integrator lens 12, which is connected to a piezoelectric element 17 on one side and a fixed spring 18 on the other side, and the piezoelectric element is connected to a pulse oscillator 19. has been done.
図示の装置を用いる実験で、従来問題となったスペック
ルノイズを除去しうろことが確認された。In experiments using the illustrated device, it was confirmed that speckle noise, which has been a problem in the past, can be removed.
以上のように本発明にれば、インテグレータレンズを用
いて光強度分布を均一化する際に、コヒーレント光への
通用で特に問題となるスペックルノイズを除去でき、レ
ーザ出力光の均一化した強度分布が得られる効果がある
。As described above, according to the present invention, when uniformizing the light intensity distribution using an integrator lens, speckle noise, which is a particular problem when applied to coherent light, can be removed, and the intensity of the laser output light is made uniform. This has the effect of providing distribution.
第１図（ａ）と（ｂ）は本発明実施例の図、第２図（ａ
）と（ｂ）は本発明実施例の概略図、第３図はエキシマ
レーザの出力光の強度分布図、第４図はレーザ照射の正
面図、
第５図は基板に照射されたレーザ光を示す平面図、
第６図は基板上に成長したシリコン膜の断面図、第７図
はインテグレータレンズを説明する図である。
図中、
１１と２１はレーザ光、
１１ａはレーザ光源、
１２はインテグレータレンズ、
１３は試料、
１４はチャンバ、
１５は窓、
１６はステージ、
１７は圧電素子、
１８はばね、
１９はパルス発振器、
２２は基板、
２３は干渉縞、
２４はシリコン膜
を示す。
特許出願人 富士通株式会社
代理人弁理士 久木元 彰
１５ λ
榛朗爽静ｊｄａ酷、１ １６ ステー
シー第２゜ １７ ル５ｔｙ１Ｂｌｔ−
ｒｓ
エキシマレ−ｖ１覆鯰７７し儒［Δヒ甲ｍ第３図
レーｒ限身寸―正、ｉｌｌ＞ロコ
第４図
１１ 第６図Figures 1 (a) and (b) are diagrams of an embodiment of the present invention, and Figure 2 (a)
) and (b) are schematic diagrams of embodiments of the present invention, Figure 3 is an intensity distribution diagram of the output light of the excimer laser, Figure 4 is a front view of laser irradiation, and Figure 5 is a diagram of the laser beam irradiated onto the substrate. FIG. 6 is a cross-sectional view of a silicon film grown on a substrate, and FIG. 7 is a diagram illustrating an integrator lens. In the figure, 11 and 21 are laser beams, 11a is a laser light source, 12 is an integrator lens, 13 is a sample, 14 is a chamber, 15 is a window, 16 is a stage, 17 is a piezoelectric element, 18 is a spring, 19 is a pulse oscillator, 22 is a substrate, 23 is an interference fringe, and 24 is a silicon film. Patent Applicant Fujitsu Ltd. Representative Patent Attorney Akira Kukimoto15
rs excimale-v1 cover catfish 77 shiyu [Δhikom figure 3 ray r limited body size - correct, ill> loco figure 4 figure 11 figure 6
Claims (4)
（１１）の光強度分布を均一化する方法において、試料
（１３）の照射面上でのビーム位置を干渉縞間隔の１／
２以上または干渉縞間隔の整数倍の範囲で往復移動させ
ることを特徴とするレーザビームの強度分布を均一化す
る方法。(1) In a method of uniformizing the light intensity distribution of the laser beam (11) using an integrator lens (12), the beam position on the irradiation surface of the sample (13) is adjusted to 1/1/2 of the interference fringe interval.
A method for making the intensity distribution of a laser beam uniform, characterized by moving the laser beam back and forth within a range of 2 or more or an integral multiple of the interference fringe interval.
／２以上または干渉縞間隔の整数倍の範囲で往復移動さ
せる特許請求の範囲第１項記載の方法。(2) Set the integrator lens (12) to 1 of the interference fringe interval.
2. The method according to claim 1, wherein the reciprocating movement is performed in a range of /2 or more or an integral multiple of the interference fringe interval.
を停止させて行い、パルスからパルスへの時間内にｄ／
２ｎ（ただし、ｄは干渉縞間隔、ｎは整数）の距離を移
動させる特許請求の範囲第１項記載の方法。(3) Use a pulsed laser and irradiate the moving sample (13)
d/d within the pulse-to-pulse time.
2. The method according to claim 1, wherein the method moves a distance of 2n (where d is the interference fringe interval and n is an integer).
はパルスからパルスへの時間）の定速移動を行って該レ
ーザを照射する特許請求の範囲第１項記載の方法。(4) Using a pulsed laser, d/2nt (however, t
2. The method according to claim 1, wherein the laser is irradiated by moving at a constant speed (time from pulse to pulse).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63002622A JPH01179908A (en) | 1988-01-11 | 1988-01-11 | Method for uniformizing intensity distribution of laser beam |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63002622A JPH01179908A (en) | 1988-01-11 | 1988-01-11 | Method for uniformizing intensity distribution of laser beam |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01179908A true JPH01179908A (en) | 1989-07-18 |
Family
ID=11534504
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63002622A Pending JPH01179908A (en) | 1988-01-11 | 1988-01-11 | Method for uniformizing intensity distribution of laser beam |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01179908A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005109460A (en) * | 2003-09-09 | 2005-04-21 | Semiconductor Energy Lab Co Ltd | Laser irradiation equipment, method of irradiating laser, and method of manufacturing semiconductor device |
| JP2006287183A (en) * | 2005-03-10 | 2006-10-19 | Ishikawajima Harima Heavy Ind Co Ltd | Laser irradiation equipment of laser annealing device |
| US7969532B2 (en) | 2005-11-15 | 2011-06-28 | Panasonic Corporation | Surface illuminator and liquid crystal display using same |
| JP2013138241A (en) * | 2008-01-07 | 2013-07-11 | Ihi Corp | Laser annealing method and device |
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| JPS61279822A (en) * | 1985-06-05 | 1986-12-10 | Canon Inc | Illuminating optical system |
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|---|---|---|---|---|
| JPS5565940A (en) * | 1978-11-13 | 1980-05-17 | Matsushita Electric Ind Co Ltd | Laser image display device |
| JPS61212816A (en) * | 1985-03-18 | 1986-09-20 | Canon Inc | Lighting equipment |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005109460A (en) * | 2003-09-09 | 2005-04-21 | Semiconductor Energy Lab Co Ltd | Laser irradiation equipment, method of irradiating laser, and method of manufacturing semiconductor device |
| JP2006287183A (en) * | 2005-03-10 | 2006-10-19 | Ishikawajima Harima Heavy Ind Co Ltd | Laser irradiation equipment of laser annealing device |
| US7969532B2 (en) | 2005-11-15 | 2011-06-28 | Panasonic Corporation | Surface illuminator and liquid crystal display using same |
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| JP2013138242A (en) * | 2008-01-07 | 2013-07-11 | Ihi Corp | Laser annealing method and device |
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