JP4882877B2

JP4882877B2 - Resist coating method and coating apparatus used therefor

Info

Publication number: JP4882877B2
Application number: JP2007150203A
Authority: JP
Inventors: 紀彦和田; 祐介尾▲崎▼; 浩正尾崎
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 2006-12-01
Filing date: 2007-06-06
Publication date: 2012-02-22
Anticipated expiration: 2027-06-06
Also published as: JP2008155194A

Description

本発明は、基板上に円形のレジスト膜を形成する塗布方法とそれに用いる塗布装置に関するものである。 The present invention relates to a coating method for forming a circular resist film on a substrate and a coating apparatus used therefor.

シリコンウエハなどの略円形の基板にレジスト膜を形成する方法としては、スピンコータを用いた塗布方法がある。このスピンコータは、基板の略中央部に大量に塗布したレジストを、基板を吸着保持して高速に回転させることで、遠心力により基板表面の略全面に一定厚みのレジスト膜を形成するものである。 As a method for forming a resist film on a substantially circular substrate such as a silicon wafer, there is a coating method using a spin coater. This spin coater forms a resist film with a constant thickness on substantially the entire surface of a substrate by centrifugal force by rotating a resist at a high speed while adsorbing and holding the substrate by applying a large amount of resist applied to a substantially central portion of the substrate. .

なお、この従来例としては、下記特許文献１がある。
特開平９−３１９０９４号公報 As this conventional example, there is Patent Document 1 below.
Japanese Patent Laid-Open No. 9-319094

上記の従来方法は、基板回転時の遠心力を利用してレジストを表面全面に拡げながら、余分なレジストは基板外へ飛ばして除去する。そのため、基板の回転数が一定の場合、基板の中心から外周部に向かうに連れて遠心力は大きくなるので、形成されるレジスト膜の厚みは、外周部に向かって薄くなりやすいという課題があった。さらに、基板の最外周部では、飛ばされなかったレジストが表面張力により盛り上がるいわゆるエッジビートが発生することで、露光の精度を低下させるという課題があった。 In the above conventional method, the resist is spread over the entire surface by utilizing the centrifugal force when the substrate is rotated, and the excess resist is removed by removing it from the substrate. For this reason, when the number of rotations of the substrate is constant, the centrifugal force increases from the center of the substrate toward the outer peripheral portion. Therefore, there is a problem that the thickness of the resist film to be formed tends to decrease toward the outer peripheral portion. It was. Furthermore, in the outermost peripheral portion of the substrate, a so-called edge beat is generated in which the resist that has not been blown is raised by the surface tension, thereby causing a problem of reducing the exposure accuracy.

そこで本発明は、エッジビートを防止して均一な厚みのレジスト膜を形成することを目的とする。 Therefore, an object of the present invention is to form a resist film having a uniform thickness while preventing edge beats.

上記目的を達成するために、本発明は、略水平に吸着保持した基板を回転させて、前記基板の略中央から外周部へ直径に沿ってノズルを移動させるとともに、このノズルからレジストを吐出させることで、前記基板の表面に渦巻状の軌跡でレジストを塗布する塗布方法であって、前記渦巻状の軌跡に沿って予め基板表面の凹凸を測定した後、この測定結果を基に前記基板とノズルとの間隔を一定に保ちながらレジストを塗布するので、基板の略中央から最外周部まで均一な厚みのレジスト膜を形成できる作用を有する。 In order to achieve the above object, according to the present invention, a substrate that is sucked and held substantially horizontally is rotated, the nozzle is moved along the diameter from the substantially center of the substrate to the outer periphery, and the resist is discharged from the nozzle. Thus, it is a coating method for applying a resist on the surface of the substrate with a spiral trajectory, and after measuring the unevenness of the substrate surface along the spiral trajectory in advance, the substrate and the substrate based on this measurement result Since the resist is applied while keeping the distance from the nozzle constant, the resist film having a uniform thickness can be formed from approximately the center of the substrate to the outermost periphery.

本発明に係るレジストの塗布方法とそれに用いる塗布装置によれば、レジストを吐出するためのノズルと併設した測定手段を、回転させた基板の直径に略沿って移動させることで、レジストを吐出する渦巻状の軌跡に沿って基板の凹凸を予め測定しておき、この測定結果を基に、ノズルと基板表面との間隔を一定に保ちながら、さらに、渦巻状の軌跡の単位長さに対して吐出量が一定となるようにレジストを塗布するので、ノズル位置により基板の周速が変化しても、レジストの膜厚を均一にすることができる作用効果を奏する。さらに、基板の最外周部を検出しておき、この最外周部のみノズルと基板の間隔を小さくするとともに、レジストの吐出量を少なくして塗布を終了することで、基板の外周部におけるエッジビートを防止することができる作用効果も同時に奏する。 According to the resist coating method and the coating apparatus used therefor according to the present invention, the resist is discharged by moving the measuring means provided along with the nozzle for discharging the resist substantially along the diameter of the rotated substrate. Pre-measure substrate irregularities along the spiral trajectory, and based on the measurement results, while maintaining a constant spacing between the nozzle and the substrate surface, and further with respect to the unit length of the spiral trajectory Since the resist is applied so that the discharge amount is constant, even if the peripheral speed of the substrate changes depending on the nozzle position, there is an effect that the thickness of the resist can be made uniform. Furthermore, by detecting the outermost peripheral part of the substrate and reducing the distance between the nozzle and the substrate only at the outermost peripheral part and reducing the resist discharge amount, the edge beat at the outer peripheral part of the substrate is completed. The effect which can prevent is also show | played simultaneously.

（実施の形態１）
以下、図を用いて本発明の一実施の形態を説明する。 (Embodiment 1)
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

図１（ａ）は、本実施の形態における基板の一例を説明する斜視図である。基板１としては、シリコンやガラス、樹脂などからなる略円形の薄板とした。 FIG. 1A is a perspective view illustrating an example of a substrate in the present embodiment. The substrate 1 was a substantially circular thin plate made of silicon, glass, resin, or the like.

図１（ｂ）は基板１の上面図であり、２は素子形成領域であり、配線や電極、各種センサや半導体素子などの機能素子を、所定の形状とピッチで配置した領域である。本実施の形態では、基板１の略中心部３と、最外周部４とには、素子形成領域２を設けない構成とし、さらにこの最外周部４に素子形成領域２にかからないように切欠きからなる認識部５を設けた。後述するが、この認識部５で、基板１を回転始動させる始点を規定するものである。尚、認識部５の他の一例としては、貫通孔や丸や十字などの記号を最外周部４に形成しても良い。 FIG. 1B is a top view of the substrate 1, and 2 is an element formation region, which is a region where functional elements such as wirings, electrodes, various sensors, and semiconductor elements are arranged at a predetermined shape and pitch. In the present embodiment, the element forming region 2 is not provided in the substantially central portion 3 and the outermost peripheral portion 4 of the substrate 1, and the outer peripheral portion 4 is notched so as not to cover the element forming region 2. A recognition unit 5 is provided. As will be described later, the recognition unit 5 defines a starting point for starting rotation of the substrate 1. As another example of the recognition unit 5, a symbol such as a through hole, a circle, or a cross may be formed on the outermost peripheral portion 4.

次に、本実施の形態におけるレジストの塗布装置の一例を説明する。 Next, an example of a resist coating apparatus in the present embodiment will be described.

図２は、本実施の形態におけるレジストの塗布装置の上面図である。基台６の中央部に基板１を吸着保持して一定の回転数で回転させる吸着回転手段７を配置し、また、角部には、基板１を複数枚収納する基板カセット８を配置している。吸着回転手段７の天面には、吸着用孔９が略中心から外周部に向けて放射状に複数形成されており、この吸着孔９により、基板１の裏面を真空吸着して保持する。基板カセット８内に収納された基板１は、脱着アーム１０で取り出された後、吸着回転手段７上に搬送され、レジストの塗布が終了後に、脱着アーム１０で取り出して、基板カセット８内に再度収納する。尚、基板カセット８は取り外しが可能であり、レジスト塗布が終了次第、取り外して次の工程へ搬送される。 FIG. 2 is a top view of the resist coating apparatus in the present embodiment. Adsorption rotation means 7 for adsorbing and holding the substrate 1 at the central portion of the base 6 and rotating it at a constant rotation number is disposed, and a substrate cassette 8 for accommodating a plurality of substrates 1 is disposed at the corner portion. Yes. A plurality of suction holes 9 are radially formed on the top surface of the suction rotating means 7 from the substantially center toward the outer periphery, and the back surface of the substrate 1 is vacuum-sucked and held by the suction holes 9. The substrate 1 stored in the substrate cassette 8 is taken out by the attachment / detachment arm 10 and then transferred onto the suction rotating means 7. After the resist application is completed, the substrate 1 is taken out by the attachment / detachment arm 10 and is again put in the substrate cassette 8. Store. The substrate cassette 8 can be removed. Upon completion of resist coating, the substrate cassette 8 is removed and transported to the next process.

また、基台６の天面には、吸着回転手段７を挟んで平行に一対の位置調整用レール１１を設け、その上に吸着回転手段７を跨ぐように、水平移動手段１２が配置されている。水平移動手段１２には、レジストを吐出するノズル１３と、基板１の凹凸を測定するための測定手段１４とを保持して上下動可能な昇降手段１５が、水平方向（ｘ方向）に移動可能に支持されている。尚、ノズル１３と測定手段１４とは、昇降手段１５に対して同一線上に並列して保持されており、ノズル１３および測定手段１４とが、吸着回転手段７の略回転中心を通るように、水平移動手段１２を位置調整用レール１１上で移動させて位置調整をする。こうすることで、ノズル１３と測定手段１４は、水平移動手段１２により吸着回転手段７の略直径に沿って、同一線上を移動することが可能となる。 Further, a pair of position adjusting rails 11 are provided in parallel on the top surface of the base 6 with the suction rotation means 7 interposed therebetween, and a horizontal movement means 12 is disposed on the top surface so as to straddle the suction rotation means 7. Yes. The horizontal moving means 12 includes a nozzle 13 for discharging a resist and a measuring means 14 for measuring the unevenness of the substrate 1, and an elevating means 15 that can move up and down is movable in the horizontal direction (x direction). It is supported by. The nozzle 13 and the measuring means 14 are held in parallel on the same line with respect to the lifting / lowering means 15, so that the nozzle 13 and the measuring means 14 pass through the approximate rotation center of the suction rotating means 7. The position is adjusted by moving the horizontal moving means 12 on the position adjusting rail 11. By doing so, the nozzle 13 and the measuring means 14 can be moved on the same line along the substantially diameter of the suction rotating means 7 by the horizontal moving means 12.

次に、図３を用いて本装置の主要部の詳細を説明する。 Next, details of the main part of the apparatus will be described with reference to FIG.

図３は、図２におけるＡ−ＡＡ断面図を示している。吸着回転手段７は、軸１６の一端に固定されており、この軸１６を、基台６の貫通部に玉軸受け、静圧軸受けなどからなる軸受け部１７を介して回動可能に支持している。また、軸１６の他端は、ジョイント１８を介して真空ポンプに接続してあり、吸着回転手段７を貫通した吸着孔９は、真空ポンプに接続されることで基板１を吸着保持する。さらに、軸１６の他端は、ギアまたはタイミングベルトなどからなる連結器１９でモータＭ₁と連結されており、このモータＭ₁を駆動することで、軸１６を介して吸着回転手段７を一定の回転数で回転させる。 FIG. 3 shows a cross-sectional view taken along the line A-AA in FIG. The suction rotation means 7 is fixed to one end of a shaft 16, and this shaft 16 is rotatably supported by a penetrating portion of the base 6 via a bearing portion 17 including a ball bearing, a static pressure bearing and the like. Yes. Further, the other end of the shaft 16 is connected to a vacuum pump via a joint 18, and the suction hole 9 penetrating the suction rotating means 7 is connected to the vacuum pump to hold the substrate 1 by suction. Further, the other end of the shaft 16 is connected to the motor M _{1 by a} coupler 19 made of a gear or a timing belt. By driving the motor M ₁ , the suction rotation means 7 is fixed via the shaft 16. Rotate at the number of revolutions.

水平移動手段１２、並びに昇降手段１５は、モータＭ₂、Ｍ₃と、バックラッシュの小さいボールネジ２０、２１と、固定板２２、２３とからなり、モータＭ₂、Ｍ₃を駆動することにより、ボールネジ２０、２１を介して固定板２２、２３と、これらに保持されているノズル１３および測定手段１４とを、それぞれ水平方向（ｘ方向）および垂直方向（ｚ方向）に移動させるものである。このようにして、ノズル１３を水平方向に移動させながらレジストを吐出させることで、基板１の表面に、一定の幅を有する渦巻状の軌跡でレジストを塗布する。 The horizontal moving means 12 and the lifting / lowering means 15 are composed of motors M ₂ and M ₃ , ball screws 20 and 21 with small backlash, and fixing plates 22 and 23, and by driving the motors M ₂ and M ₃ , The fixing plates 22 and 23 and the nozzle 13 and the measuring means 14 held by the ball screws 20 and 21 are moved in the horizontal direction (x direction) and the vertical direction (z direction), respectively. In this way, the resist is ejected while moving the nozzle 13 in the horizontal direction, whereby the resist is applied to the surface of the substrate 1 with a spiral locus having a certain width.

次に、上記構成のレジストの塗布装置を用いたレジストの塗布方法を説明する。 Next, a resist coating method using the resist coating apparatus having the above configuration will be described.

まず初めに、基板カセット８により複数枚投入された基板１を、脱着アーム１０を用いて取り出し、吸着回転手段７上に搬送して位置決めを行った後、真空ポンプを作動させることで、吸着孔９を介して基板１を吸着保持する。このとき、ノズル１３および測定手段１４は、脱着アーム１０の動作に干渉しない位置に退避しておく。また、ノズル１３および測定手段１４は、基板１の略中心を通るように、予め水平移動手段１２の位置を調整しておき、レジストの塗布時または、後述する基板１表面の凹凸測定時に、ノズル１３および測定手段１４とを、基板１の直径に沿って移動させるものである。尚、図１で説明したように、本実施の形態では、基板１の略中心部３は、素子などを形成しない領域とした。そのため、上記の水平移動手段１２の位置調整は、この略中心部３から外れない程度とすることで、位置調整の時間を短縮することができる。 First, a plurality of substrates 1 loaded by the substrate cassette 8 are taken out by using the desorption arm 10, transported onto the suction rotating means 7, positioned, and then the vacuum pump is operated so that the suction hole 9 holds the substrate 1 by suction. At this time, the nozzle 13 and the measuring means 14 are retracted to a position where they do not interfere with the operation of the detachable arm 10. In addition, the nozzle 13 and the measuring means 14 are adjusted in advance so that the position of the horizontal moving means 12 passes through the approximate center of the substrate 1, and the nozzle 13 and the measuring means 14 are used when applying resist or measuring irregularities on the surface of the substrate 1 described later. 13 and the measuring means 14 are moved along the diameter of the substrate 1. As described with reference to FIG. 1, in the present embodiment, the substantially central portion 3 of the substrate 1 is a region where no element or the like is formed. Therefore, the position adjustment time can be shortened by adjusting the position of the horizontal movement means 12 so as not to deviate from the substantially central portion 3.

次に、回避させていた測定手段１４を、基板１の略中心へ移動させて、一定の高さに調整した後、モータＭ₁を駆動させて、吸着回転手段７上の基板１を一定の回転数で回転させる。そして、この回転数が安定したのを確認した後、測定手段１４を基板１の略中心から外周部へ向けて、水平移動手段１２により一定の速度で移動させながら、基板１表面の凹凸を測定する。尚、測定手段１４で測定する凹凸のデータは、基板１自体の局所的な凹凸やうねり、吸着回転手段７の回転振れも含むものである。測定手段１４を水平移動させる開始タイミングは、基板１の最外周部４に設けた切欠きや貫通孔、文字や図形パターンなどからなる認識部５を、カメラ等の認識手段で認識することで決定する。測定手段１４は、基板１の表面に有する一定の領域の凹凸を測定しながら、基板１の直径に沿って移動するので、この測定軌跡は、基板１の略中心（移動開始点）を始点とした渦巻状の軌跡を描くことになる。尚、測定手段１４としては、レーザ変位計などを使用して非接触状態で測定を行い、Ａ−Ｄ変換して、水平移動手段１２の位置座標データとともに測定データを制御機器（図示せず）内のメモリなどに記録、保存する。そして、これらのデータから、ノズル１３と基板１との間隔を補正する補正データを作成する。 Next, the measuring means 14 that has been avoided is moved to approximately the center of the substrate 1 and adjusted to a certain height, and then the motor M ₁ is driven to keep the substrate 1 on the suction rotating means 7 constant. Rotate at the number of revolutions. Then, after confirming that the rotational speed is stable, the unevenness on the surface of the substrate 1 is measured while moving the measuring means 14 from the substantially center of the substrate 1 to the outer peripheral portion at a constant speed by the horizontal moving means 12. To do. The unevenness data measured by the measuring means 14 includes local unevenness and waviness of the substrate 1 itself, and rotational vibration of the suction rotating means 7. The start timing for horizontally moving the measuring means 14 is determined by recognizing the recognition section 5 formed of a notch, a through hole, a character, a graphic pattern, or the like provided in the outermost peripheral portion 4 of the substrate 1 with a recognition means such as a camera. To do. The measuring means 14 moves along the diameter of the substrate 1 while measuring the unevenness of a certain region on the surface of the substrate 1, so that the measurement trajectory starts from the approximate center (movement start point) of the substrate 1. A spiral trajectory will be drawn. As the measuring means 14, measurement is performed in a non-contact state using a laser displacement meter or the like, A / D conversion is performed, and the measurement data together with the position coordinate data of the horizontal moving means 12 is controlled by a control device (not shown). Record and save in the internal memory. Then, correction data for correcting the interval between the nozzle 13 and the substrate 1 is created from these data.

次に、ノズル１３を、測定手段１４と同様に、基板１の略中心に移動させて一定の高さに調整した後、基板１を回転させて、外周部に向けて水平移動させながらレジストを吐出させることで塗布を開始する。ノズル１３から吐出されたレジストは、基板１の略中心を起点として、外周部に向かって一定の幅を有する渦巻状の軌跡を描いて塗布される。この塗布直後の幅は、レジストの粘度やチクソ性が同等の場合、基板１とノズル１３との間隔で決定する。したがって、レジストの吐出時は、上述した補正データを基に、昇降手段１５を駆動させてノズル１３の高さを補正し、常に基板１とノズル１３とが一定の間隔を保つようにすることで、一定の幅のレジストを塗布するようにする。 Next, the nozzle 13 is moved to substantially the center of the substrate 1 and adjusted to a certain height in the same manner as the measuring means 14, and then the substrate 1 is rotated to move the resist horizontally while moving toward the outer periphery. Application is started by discharging. The resist discharged from the nozzle 13 is applied in a spiral locus having a certain width from the substantially center of the substrate 1 toward the outer periphery. The width immediately after coating is determined by the distance between the substrate 1 and the nozzle 13 when the resist viscosity and thixotropy are the same. Therefore, when the resist is discharged, the elevation means 15 is driven based on the correction data described above to correct the height of the nozzle 13 so that the substrate 1 and the nozzle 13 are always kept at a constant interval. Then, a resist having a certain width is applied.

また、ノズル１３を水平移動させるタイミングは、基板１の最外周部４に設けた切欠きや貫通孔、文字や図形パターンなどからなる認識部５をカメラ等で認識することで決定するのであるが、必ず凹凸測定時における測定手段１４の移動開始タイミングと合致させる。こうすることで、凹凸測定における測定手段１４の測定軌跡（渦巻状の軌跡）と、ノズル１３で塗布されたレジストが描く渦巻状の軌跡とを合致させることができる。 The timing for horizontally moving the nozzle 13 is determined by recognizing the recognition unit 5 formed of a notch, a through hole, a character, a graphic pattern, or the like provided in the outermost peripheral portion 4 of the substrate 1 with a camera or the like. Always match the movement start timing of the measuring means 14 at the time of unevenness measurement. By doing so, the measurement trajectory (spiral trajectory) of the measuring means 14 in the unevenness measurement can be matched with the spiral trajectory drawn by the resist applied by the nozzle 13.

基板１の回転数は、使用するレジストの粘度やチクソ性、基板１の外形サイズなどを考慮して適宜設定する。本実施の形態では、２０ミクロン以上の厚みの均一なレジスト膜を形成するため、粘度が１０００ｍＰａ・ｓ以上の高粘度タイプのレジストを選択し、基板外周部での遠心力によるレジストの広がりを小さくするため、基板１の回転数は概ね５０ｒｐｍ以下と設定した。 The number of rotations of the substrate 1 is appropriately set in consideration of the viscosity and thixotropy of the resist to be used, the outer size of the substrate 1, and the like. In this embodiment, in order to form a uniform resist film having a thickness of 20 microns or more, a high-viscosity resist having a viscosity of 1000 mPa · s or more is selected, and the spread of the resist due to the centrifugal force at the outer periphery of the substrate is reduced. Therefore, the rotation speed of the substrate 1 is set to approximately 50 rpm or less.

また、ノズル１３の移動速度は、基板１の回転速度と塗布されたレジストの幅を考慮して決定する。すなわち、基板１が一回転する間にノズル１３を、塗布されたレジストの幅分だけ移動するようにすることで、隣り合うレジストの軌跡が重畳されることが無いようにする。 The moving speed of the nozzle 13 is determined in consideration of the rotation speed of the substrate 1 and the width of the applied resist. That is, by moving the nozzle 13 by the width of the applied resist while the substrate 1 is rotated once, the locus of the adjacent resist is prevented from being superimposed.

さらに、ノズル１３から吐出するレジストの吐出量は、渦巻状の軌跡の単位長さに対して常に一定量となるように制御する。本実施の形態では、基板１の回転数は常に一定にしてレジストを塗布するため、ノズル１３直下における基板１の回転速度は、外周部に移動する移動量に比例して速くなる。そのため、横軸をノズル１３の移動量、縦軸をレジストの吐出量としたとき、図４に示すように、少なくとも素子形成領域２（図１）では、移動量に比例して吐出量を増加させてレジストを塗布する。このようにすることで、塗布されたレジストの隣り合う軌跡は、互いに重畳することはなく、さらにこれら軌跡同士の界面部で生じる凹みは、レジストが広がることで解消され、その結果、基板１の表面すなわち素子形成領域２上に、均一な厚みのレジスト膜が形成される。 Further, the discharge amount of the resist discharged from the nozzle 13 is controlled so as to be always a constant amount with respect to the unit length of the spiral trajectory. In the present embodiment, since the resist is applied with the rotation speed of the substrate 1 being always constant, the rotation speed of the substrate 1 immediately below the nozzle 13 increases in proportion to the amount of movement to the outer peripheral portion. Therefore, when the horizontal axis is the movement amount of the nozzle 13 and the vertical axis is the resist discharge amount, as shown in FIG. 4, at least in the element formation region 2 (FIG. 1), the discharge amount increases in proportion to the movement amount. And apply a resist. By doing so, the adjacent tracks of the applied resist do not overlap each other, and further, the dent generated at the interface between these tracks is eliminated by spreading the resist, and as a result, the substrate 1 A resist film having a uniform thickness is formed on the surface, that is, the element formation region 2.

最後に、ノズル１３を基板１の最外周部４(図１)で水平移動を停止させるとともに、レジストの吐出も停止させて塗布を終了する。この最外周部４では、ノズル１３は水平移動を停止させるので、渦巻状の軌跡ではなく、円の軌跡を描き、始点と終点とが重畳しないように、基板１を略一回転させた後に停止させる。また、最外周部４では、基板１とノズル１３との間隔を、少なくとも素子形成領域２よりも狭くするとともに、レジストの吐出量も図４に示すように少なくする。こうすることで、基板１の最外周部４に塗布されたレジストの厚みのみを、他の素子形成領域２よりも薄くすることができるので、レジストの盛り上がり（エッジビート）が発生した場合であっても、その盛り上がりの高さを、素子形成領域２に塗布されたレジストよりも低くすることができる。そして、コンタクト露光を行う際に、マスクとレジストとを確実に密着させることができるので、露光の精度を高くすることができる。尚、この最外周部４におけるレジストの吐出量は、素子形成領域２での吐出量に対して概ね３０％以下とすることで、エッジビートの無い良好な塗布面が得られた。また、最外周部４の認識は、予め基板１の素子形成領域２を制御機器に入力しておき、水平移動手段１２の位置データと比較して認識するものである。 Finally, the horizontal movement of the nozzle 13 is stopped at the outermost peripheral portion 4 (FIG. 1) of the substrate 1 and the discharge of the resist is also stopped to complete the coating. In the outermost peripheral portion 4, the nozzle 13 stops horizontal movement, so that a circular trajectory is drawn instead of a spiral trajectory, and the substrate 1 is stopped after approximately one rotation so that the start point and the end point do not overlap. Let In the outermost peripheral portion 4, the distance between the substrate 1 and the nozzle 13 is made at least narrower than that of the element formation region 2, and the resist discharge amount is also reduced as shown in FIG. By doing so, only the thickness of the resist applied to the outermost peripheral portion 4 of the substrate 1 can be made thinner than the other element formation regions 2, and this is the case where the resist swells (edge beat) occurs. However, the height of the rise can be made lower than the resist applied to the element formation region 2. And when performing contact exposure, since a mask and a resist can be stuck firmly, the precision of exposure can be made high. Note that, by setting the discharge amount of the resist in the outermost peripheral portion 4 to approximately 30% or less with respect to the discharge amount in the element forming region 2, a good coated surface without an edge beat was obtained. Further, the recognition of the outermost peripheral portion 4 is performed by inputting the element formation region 2 of the substrate 1 in advance to the control device and comparing it with the position data of the horizontal moving means 12.

（実施の形態２）
以下、図を用いて本発明の別の一実施の形態を説明する。尚、実施の形態１と同じ箇所に関しては説明を簡略化して、主に相違点のみを説明する。 (Embodiment 2)
Hereinafter, another embodiment of the present invention will be described with reference to the drawings. In addition, regarding the same part as Embodiment 1, description is simplified and only a different point is mainly demonstrated.

図５は、図２における別のＡ−ＡＡ断面図を示している。実施の形態１との相違点は、吸着回転手段７の外周部または、ノズル１３の少なくともいずれか一方に加熱手段２４、２５を設けたことである。加熱手段２４、２５は、シーズヒータやカーボンヒータ、セラミックヒータなどからなり、吸着回転手段７に設ける場合は、その外周部のみに一定の幅で環状に設ける。ノズル１３に設ける場合は、ノズル１３内やその背面、またはノズル１３の周囲を覆うように設ける。いずれに設ける場合であっても、基板１上に塗布されたレジストを加熱して昇温するために用いるものである。 FIG. 5 shows another A-AA cross-sectional view in FIG. The difference from the first embodiment is that heating means 24 and 25 are provided on at least one of the outer peripheral portion of the suction rotation means 7 and the nozzle 13. The heating means 24 and 25 are composed of a sheathed heater, a carbon heater, a ceramic heater, or the like. When provided in the nozzle 13, it is provided so as to cover the inside of the nozzle 13, the back surface thereof, or the periphery of the nozzle 13. In any case, the resist applied on the substrate 1 is used for heating and raising the temperature.

本発明の塗布装置は、ノズル１３を基板１の直径に沿って、その略中心から外周部へ向けて水平に移動させるとともに、レジストを吐出させることで、渦巻状に塗布する。そのため、基板１上に塗布されたレジストには遠心力が作用して、外周部になるほどその遠心力は大きくなり、略中央部のレジストは外周部に引っ張られて薄くなる。また、ノズル１３が終点位置に到達すると同時に、吸着回転手段７を停止させた場合、外周部に塗布されたレジストは、遠心力で充分に広がらず、図６に示すように、基板１の略中央部で薄く、外周部で逆に厚くなる。 In the coating apparatus of the present invention, the nozzle 13 is applied in a spiral shape by moving the nozzle 13 horizontally along the diameter of the substrate 1 from its substantially center toward the outer periphery and discharging the resist. Therefore, a centrifugal force acts on the resist applied on the substrate 1, and the centrifugal force increases toward the outer peripheral portion, and the resist in the substantially central portion is pulled to the outer peripheral portion and becomes thin. Further, when the suction rotation means 7 is stopped at the same time as the nozzle 13 reaches the end point position, the resist applied to the outer peripheral portion is not sufficiently spread by the centrifugal force, and as shown in FIG. It is thin at the center and thicker at the outer periphery.

上記の厚みばらつきに対して、本実施の形態では、以下に説明する二つの方法を用いて均一化した。まず初めに基板１の略中央部のみ、ノズル１３から吐出させる単位時間あたりの吐出量を多くしてレジストを塗布する。尚、略中央部とは、基板１の中心から、その半径の１０％程度の領域である。また、レジストの吐出量は、略中央部以外の吐出量に対して概ね１０〜２０％程度多くする。 In the present embodiment, the above thickness variation is uniformed by using the two methods described below. First, the resist is applied to only the substantially central portion of the substrate 1 by increasing the discharge amount per unit time discharged from the nozzle 13. The substantially central portion is a region that is about 10% of the radius from the center of the substrate 1. Further, the resist discharge amount is increased by about 10 to 20% with respect to the discharge amount other than the substantially central portion.

次に、基板１の外周部において吐出させる、または塗布された後のレジストを加熱することである。レジストの粘度は、その温度が高くなるほど小さくなりチクソ性も改善される傾向にある。そのため、特に基板１の外周部において吐出されるレジストを、吐出時であれば加熱手段２５でノズル１３を加熱することで、また、塗布後であれば、加熱手段２４で基板１上のレジストを加熱することで、レジストの流動性を高めて外周部における厚みの均一性を高める。このように、レジストを加熱してその流動性を高めることにより、基板１の外周部におけるレジストを最小限の回転による遠心力で拡げることにより、その厚みを略中心部と等しく、均一化するものである。 Next, the resist after being discharged or applied on the outer peripheral portion of the substrate 1 is heated. The resist viscosity tends to decrease as the temperature increases, and the thixotropy tends to improve. Therefore, the resist discharged on the outer periphery of the substrate 1 is heated by the heating means 25 when discharging, and the resist on the substrate 1 is heated by the heating means 24 after coating. By heating, the fluidity of the resist is increased and the uniformity of the thickness at the outer peripheral portion is increased. In this way, by heating the resist to increase its fluidity, the resist on the outer peripheral portion of the substrate 1 is expanded by centrifugal force with minimal rotation, so that its thickness is substantially equal to the central portion and uniformized. It is.

尚、レジストの加熱温度としては、プリベーク温度以下で、かつ基板１の略中央部における温度に対して２０〜３０℃程度高くすれば良い。基板１の略中央部で、室温でレジストを塗布した場合、外周部では概ね４０〜５０℃程度とする。また、レジストの温度を高めて塗布する基板１の外周部としては、その半径の概ね１０〜２０％の領域とする。 The heating temperature of the resist may be not higher than the pre-baking temperature and higher by about 20 to 30 ° C. than the temperature at the substantially central portion of the substrate 1. When a resist is applied at room temperature at a substantially central portion of the substrate 1, the outer peripheral portion is set to approximately 40 to 50 ° C. Further, the outer peripheral portion of the substrate 1 to be coated at a higher resist temperature is set to an area of approximately 10 to 20% of the radius.

上記の塗布方法を、８インチのシリコン基板に適用して、最外周の１０ｍｍの領域に、レジストの温度を高めて塗布することにより、基板１におけるレジストの塗布厚みばらつきを、目標厚みの５％以内と均一化することができた。 By applying the above coating method to an 8-inch silicon substrate and applying the resist at a temperature of 10 mm on the outermost periphery, the resist coating thickness variation on the substrate 1 is 5% of the target thickness. And could be homogenized within.

上述した塗布方法を用いることにより、吸着回転手段７を余計に回転させることなく、最小限の回転でレジストの厚みを均一化して塗布することができ、生産性を高めることができる。 By using the above-described coating method, it is possible to apply the resist with a uniform thickness with a minimum rotation without excessively rotating the suction rotating means 7, thereby improving productivity.

尚、上述したレジストの塗布方法とそれに用いる塗布装置は、本実施の形態に限定されるものではなく、単層または多層のレジストを形成して、露光および現像を複数回繰り返す、また、構造体を形成するため、高粘度のレジストを用いて２０ミクロン以上のレジスト膜を形成するＭＥＭＳプロセスを用いた電子部品の製造方法とそれに用いる製造装置にも適用可能である。 The resist coating method and the coating apparatus used therefor are not limited to the present embodiment, and a single-layer or multilayer resist is formed, and exposure and development are repeated a plurality of times. Therefore, the present invention is also applicable to a method for manufacturing an electronic component using a MEMS process for forming a resist film of 20 microns or more using a high-viscosity resist and a manufacturing apparatus used therefor.

本発明に係るレジストの塗布方法とそれに用いる塗布装置によれば、レジストを吐出するためのノズルと併設した測定手段を、回転させた基板の直径に略沿って移動させることで、レジストを吐出する渦巻状の軌跡に沿って基板の凹凸を予め測定しておき、この測定結果を基に、ノズルと基板表面との間隔を一定に保ちながら、さらに、渦巻状の軌跡の単位長さに対して吐出量が一定となるようにレジストを塗布するので、ノズル位置により基板の周速が変化しても、レジストの膜厚を均一にすることができる作用効果を奏する。さらに、基板の最外周部を検出しておき、この最外周部のみノズルと基板の間隔を小さくするとともに、レジストの吐出量を少なくして塗布を終了することで、基板の外周部におけるエッジビートを防止することができる作用効果も同時に奏するので、基板上に円形のレジスト膜を形成する塗布方法とそれに用いる塗布装置に有用である。 According to the resist coating method and the coating apparatus used therefor according to the present invention, the resist is discharged by moving the measuring means provided along with the nozzle for discharging the resist substantially along the diameter of the rotated substrate. Pre-measure substrate irregularities along the spiral trajectory, and based on the measurement results, while maintaining a constant spacing between the nozzle and the substrate surface, and further with respect to the unit length of the spiral trajectory Since the resist is applied so that the discharge amount is constant, even if the peripheral speed of the substrate changes depending on the nozzle position, there is an effect that the thickness of the resist can be made uniform. Furthermore, by detecting the outermost peripheral part of the substrate and reducing the distance between the nozzle and the substrate only at the outermost peripheral part and reducing the resist discharge amount, the edge beat at the outer peripheral part of the substrate is completed. Therefore, it is useful for a coating method for forming a circular resist film on a substrate and a coating apparatus used therefor.

（ａ）本発明の一実施の形態におけるレジストを塗布する基板の一例を示す斜視図、（ｂ）同基板の上面図(A) The perspective view which shows an example of the board | substrate which apply | coats the resist in one embodiment of this invention, (b) The top view of the board | substrate 本発明の一実施の形態を説明する塗布装置の上面図The top view of the coating device explaining one embodiment of the present invention 同図の要部を説明する図２のＡ−ＡＡ断面図2 is a cross-sectional view taken along the line A-AA in FIG. 本発明の一実施の形態におけるノズルから吐出するレジストの吐出量を説明する図The figure explaining the discharge amount of the resist discharged from the nozzle in one embodiment of this invention 本発明の別の実施の形態を説明する塗布装置の要部断面図Sectional drawing of the principal part of the coating device explaining another embodiment of this invention 本実施の形態におけるレジストの塗布厚みを説明する図The figure explaining the application | coating thickness of the resist in this Embodiment

Explanation of symbols

１基板
５認識部
７吸着回転手段
１２水平移動手段
１３ノズル
１４測定手段
１５昇降手段
２４加熱手段
２５加熱手段 DESCRIPTION OF SYMBOLS 1 Substrate 5 Recognition part 7 Suction rotation means 12 Horizontal movement means 13 Nozzle 14 Measuring means 15 Lifting means 24 Heating means 25 Heating means

Claims

By rotating the substrate that is sucked and held substantially horizontally, the nozzle is moved along the diameter from the substantially center of the substrate to the outer periphery, and the resist is discharged from the nozzle, whereby a spiral trajectory is formed on the surface of the substrate. In the coating method of applying a resist, the unevenness of the substrate surface is measured in advance along the spiral trajectory, and then the resist is applied while keeping the distance between the substrate and the nozzle constant based on the measurement result. Resist application method.

The resist coating method according to claim 1, wherein a recognition portion is provided on an outer peripheral portion of the substrate, and a spiral locus for applying the resist using the recognition portion is matched with a locus for unevenness measurement.

The resist coating method according to claim 2, wherein the resist is ejected so that the amount of the resist ejected is always constant with respect to the unit length of the spiral trajectory.

The resist coating method according to claim 3, wherein only the outermost peripheral portion of the substrate is made to have a small gap between the nozzle and the substrate and reduce the resist discharge amount to finish the coating.

The resist coating method according to claim 4, wherein the resist is applied by increasing the discharge amount of the resist only in a certain region at substantially the center of the substrate.

The resist coating method according to claim 5, wherein the resist is discharged at a temperature that is discharged at the outermost peripheral portion at least higher than a temperature discharged at a substantially central portion.

A suction rotating means for sucking and holding the substrate substantially horizontally and rotating, a nozzle for discharging a resist disposed above the suction rotating means, a measuring means for measuring irregularities on the surface of the substrate, and these nozzles and measuring means A resist coating apparatus comprising: lifting and lowering means for supporting and moving up and down; and horizontal moving means for supporting and moving the lifting means horizontally along the diameter of the suction rotation means. Then, after measuring the unevenness of the surface in advance while moving the measuring means along the diameter direction of the substrate, the resist is adjusted while correcting the distance between the substrate and the nozzle to be always constant based on the measurement result. A resist coating device to be discharged.

8. The resist coating apparatus according to claim 7, further comprising a recognizing unit for recognizing the recognition unit of the substrate to match the operation start timing of the nozzle and the measuring unit.

By calculating the peripheral speed of the substrate from the position data of the horizontal moving means and increasing the resist discharge amount in proportion to this peripheral speed, this discharge amount is always a constant amount with respect to the unit length of the spiral trajectory. The resist coating apparatus according to claim 8, wherein the resist is applied so as to be discharged.

10. The outermost peripheral portion of the substrate is calculated from the position data of the horizontal moving means, and only the outermost peripheral portion reduces the distance between the nozzle and the substrate and reduces the resist discharge amount to finish the application. The resist coating apparatus as described.

The resist coating apparatus according to claim 9, wherein the resist coating apparatus is applied by increasing the resist discharge amount only in a substantially central region.

The resist coating apparatus according to claim 11, wherein the nozzle includes a heating unit for heating the resist, and the resist is applied at a temperature higher than that of the center at the outer peripheral portion.

The resist coating apparatus according to claim 11, wherein the adsorption rotating unit includes a heating unit at an outer peripheral portion thereof, and applies the resist while heating the outer peripheral portion of the substrate adsorbed by the heating unit.