JP3910017B2

JP3910017B2 - Film formation method

Info

Publication number: JP3910017B2
Application number: JP2001006305A
Authority: JP
Inventors: 泰一郎青木; 彰彦中村; 康爾上田
Original assignee: Tokyo Ohka Kogyo Co Ltd
Current assignee: Tokyo Ohka Kogyo Co Ltd
Priority date: 2001-01-15
Filing date: 2001-01-15
Publication date: 2007-04-25
Anticipated expiration: 2021-01-15
Also published as: JP2002204996A

Description

【０００１】
【発明の属する技術分野】
本発明はガラス基板や半導体ウェーハなどの板状被処理物の表面に被膜を形成するための塗布方法及び塗布装置、更にはこの塗布方法及び塗布装置を組み込んだ被膜形成方法及び被膜形成装置に関する。
【０００２】
【従来の技術】
ガラス基板や半導体ウェーハなどの板状被処理物表面にレジスト膜やＳＯＧ膜を形成する方法として、回転塗布方式とスリットノズル方式がある。
【０００３】
回転塗布方式はスピンナーで板状被処理物を高速回転させ、板状被処理物の中心に滴下した塗布液を遠心力によって拡散せしめる方式であり、例えば特開平３−５６１６３号公報に開示されている。特に、この先行技術にあっては、スピンナーヘッドの上面に板状被処理物が嵌まり込む凹部を形成している。
【０００４】
また、スリットノズル方式は、米国特許第４,６９６,８８５号公報などに開示されており、板状被処理物と同程度の幅を有するスリットノズルから板状被処理物に向けて塗布液をカーテン状に滴下しつつ相対的に移動せしめることで所定範囲に塗膜を形成する方式である。
【０００５】
【発明が解決しようとする課題】
回転塗布方式にあっては、供給した塗布液のうち被膜形成に関与する塗布液が５％程度と少なく、殆どが遠心力によって飛散してしまう。また、厚い被膜を得ることができないという課題もある。
さらに、板状被処理物の寸法は大きくなっていくにもかかわらず、その厚みはほとんど変わらない為、板状被処理物の搬送時等にその自重によって撓んでしまう。
【０００６】
スリットノズル方式によれば、塗布液の無駄が少なくなり且つ被膜の膜厚を厚くすることもできる。しかしながら、スリットノズル方式にあっては、塗布開始位置と塗布終了位置における膜厚が表面張力の影響により他の個所に比べて極端に厚くなるという課題がある。
【０００７】
【課題を解決するための手段】
上記課題を解決すべく、本発明に係る被膜形成方法は、トレイを用いることを特徴とする。このトレイには凹部が形成され、この凹部に板状被処理物を嵌め込むとトレイ表面と板状被処理物表面とが略面一になる。そしてこの状態で、塗布開始位置及び塗布終了位置が板状被処理物の端部を外れたトレイ表面となるようにスリットノズルを用いて塗布する。
【０００８】
斯かる構成とすることで、塗膜の始端と終端はトレイ表面と板状被処理物表面間に連続して形成されるので、板状被処理物の端部において膜厚が厚くなることがなく、板状被処理物全面に亘って均一な厚みの塗膜が形成される。
さらに、トレイに嵌め込むことで搬送時等で生じる板状被処理物の自重による撓みを防止することができる。
【０００９】
請求項１に係る被膜形成方法は、板状被処理物の平面形状よりも若干大きめの相似形で深さが板状被処理物と等しいか若干浅くされた凹部を形成したトレイを板状被処理物の搬送ラインに移動可能に配置し、またこの搬送ラインに沿って、塗布装置、ベーク装置、冷却装置および洗浄装置を設け、前記トレイの凹部に板状被処理物を嵌め込んだ状態で、トレイとともに板状被処理物を前記塗布装置、ベーク装置、冷却装置および洗浄装置の順に送り込んで各装置で処理することで板状被処理物の表面に被膜を形成するようにした。
また請求項２に係る被膜形成方法は、板状被処理物の平面形状よりも若干大きめの相似形で深さが板状被処理物と等しいか若干浅くされた凹部を形成したトレイを板状被処理物の搬送ラインに移動可能に配置し、またこの搬送ラインに沿って、塗布装置及び加熱装置を設け、前記トレイの凹部に板状被処理物を嵌め込んだ状態で、トレイとともに板状被処理物を前記塗布装置及び加熱装置の順に送り込んで各装置で処理し、この後トレイから板状被処理物を外し、トレイについては洗浄処置及び温調処理を行った後に前記塗布装置の箇所において待機させ、トレイから外した板状被処理物については冷却処理、洗浄処理及び乾燥処理を施すようにした。
【００１０】
加熱処理と冷却処理が終了するまで、換言すれば液状の塗膜が固体状の被膜になるまでトレイ内に入れておき。固まった後に洗浄装置（エッジリンス）で端部の被膜を切り離すことで、端縁の厚みも中央部と変わらない被膜が得られる。
【００１１】
【発明の実施の形態】
以下に本発明の実施の形態を添付図面に基づいて説明する。図１は本発明に係る塗布装置を組み込んだ被膜形成装置の全体構成図であり、被膜形成装置は板状被処理物の搬送ラインに沿って、上流側から順に塗布装置１０、ベーク装置２０、冷却装置３０および洗浄装置４０が配置され、これらの装置間にレール５０が設けられ、このレール５０上をトレイ６０に嵌め込まれた板状被処理物Ｗが搬送される。なお、レール５０の代わりにベルトコンベアを用いてもよい。
【００１２】
即ち、トレイ６０は全ての装置において共通して用いられる。このトレイ６０の構造を図２に基づき塗布装置１０の構造に合わせて説明する。
【００１３】
塗布装置１０はカップ１１内にトレイ６０が載置され、このトレイ６０の上方にスリットノズル１２が設けられている。カップ１１及びトレイ６０の平面形状は板状被処理物Ｗの形状に合わせ、板状被処理物Ｗがガラス基板の場合には矩形状または正方形をなし、板状被処理物Ｗが半導体ウェーハの場合には円形とする。
【００１４】
トレイ６０の上面には凹部６１が形成されている。この凹部６１の平面形状は板状被処理物Ｗよりも若干大きな相似形とされ、凹部６１に板状被処理物Ｗを嵌め込んだ状態で、板状被処理物Ｗと凹部６１内面との間には０.０５ｍｍ程度の隙間が形成される。また、凹部６１の深さは板状被処理物Ｗの厚みと等しいか、これよりも若干浅くしておく。
【００１５】
更に、カップ１１及びトレイ６０の中央部には開口１３、６２が形成され、これら開口１３、６２内にチャック１４が臨んでいる。このチャック１４をトレイ６０よりも上昇せしめ、位置決めされた板状被処理物Ｗの下面を真空若しくは静電的に吸着し、次いでチャック１４を下降せしめることで、前記したように板状被処理物Ｗは凹部６１内に嵌まり込む。このとき、板状被処理物Ｗの表面とトレイ６０の表面は略面一になる。
【００１６】
一方、スリットノズル１２はトレイ６０上面と一定の間隔をあけて往復水平移動可能とされ、移動開始位置即ち塗布開始位置、及び移動停止位置即ち塗布終了位置は図２にも示すように板状被処理物Ｗの端部を外れたトレイ６０の表面まで伸ばしている。その結果、塗膜１５は板状被処理物Ｗの端部を若干食み出た部分まで形成される。
このとき、塗布手段としては、上記スリットノズルに限定されるものではなく、アプリケータ、ドクターブレード等を用いてもよいことはいうまでもない。さらに、塗布後または塗布時にスキージしてもよい。
【００１７】
次いで、塗膜１５が形成された板状被処理物Ｗはトレイ６０に嵌め込まれたままベーク装置２０までレール５０を介して搬送される。塗布装置１０のカップ１１内からレール５０上へのトレイ６０の移し替えはロボット等によって行う。
【００１８】
図３に示すように、ベーク装置２０内にはホットプレート２１と、このホットプレート２１を囲むように筒状のカバー２２を設けている。これらホットプレート２１およびカバー２２は何れも昇降動可能とされている。
【００１９】
上記のベーク装置２０内で塗膜１５を加熱することで液状の塗膜は固化して被膜になる。加熱後は冷却装置３０内で冷却される。冷却装置３０内はホットプレートの代わりにクールプレートが配置されるだけで、他はベーク装置２０と同一のため、説明は省略する。
【００２０】
洗浄装置４０内には図４に示すように、リンス液（洗浄液）を噴出する上下のノズル４１、４２が配置されている。
上ノズル４１は、図４（ａ）に示すように、板状被処理物Ｗの端縁部に向けて斜めに洗浄液を噴出し、被膜１５'の端縁部分を溶解し、端縁部において膜厚が厚くなった部分を除去する。この除去する個所はトレイと板状被処理物Ｗの境界部か、ややトレイにかかっているので、残存膜厚は板状被処理物Ｗ上の厚みと同じかやや薄くなり、板状被処理物の表面全域に亘って均一な被膜１５'が形成される。
【００２１】
次いで洗浄装置４０では、図４（ｂ）に示すように、チャック４３を上昇せしめ、下ノズル４２によって板状被処理物Ｗの端縁部の裏面に付着している塗布液などを除去するとともにトレイ６０の凹部６１も洗浄する。
【００２２】
本発明に係る被膜形成装置の別実施例を次に示す。尚、図５には処理の流れを説明したブロック図を示す。
カセットケースから板状被処理物Ｗを搬送装置で取り出し、塗布装置１０上に載置されたトレイ６０に形成されている凹部６１に嵌め込む。そのままトレイごと塗布装置、ベーク処理を行う。この後、板状被処理物Ｗをトレイ６０から外し、トレイ６０はトレイ用の洗浄装置で洗浄され、温調装置に搬送されて温調された後に塗布装置１０上に載置され、次の板状被処理物Ｗが嵌め込まれるまで待機する。トレイの数はスループットに合わせて適宜増減する。一方、トレイ６０から外された板状被処理物Ｗは搬送装置により冷却装置まで搬送され、冷却に続いて、洗浄（エッジリンス）、乾燥などの処理を行い、処理済用収納カセットケースに納められる。
【００２３】
さらに別実施例として、トレイ６０の凹部６１に嵌めこまれた板状被処理物Ｗを、トレイ６０と一体化して収納カセット内に収納し、板状被処理物Ｗの搬送に際しては、トレイ６０と一体的に搬送し、各種処理を施すようにしてもよい。
【００２４】
【発明の効果】
以上に説明したように本発明によれば、板状被処理物の全面に均一な厚みの塗膜を形成することができ、この塗膜を加熱処理、冷却処理、洗浄処理して得られる被膜も端縁部での盛り上がりのない均一な厚さの被膜とすることができる。
したがって、本発明はバンプ工程に必要な厚さ２０μｍ以上の被膜の形成に適しており、１００μｍの厚さの均一な被膜を形成することも可能である。
また、トレイに載せたまま全ての処理を行うことで、板状被処理物Ｗが自重により撓むということはなくなる。
【図面の簡単な説明】
【図１】本発明に係る塗布装置を組み込んだ被膜形成装置の全体構成図
【図２】塗布装置の構造を説明する断面図
【図３】ベーク装置の構造を説明する断面図
【図４】（ａ）は洗浄装置におけるエッジリンスを説明した図、（ｂ）は洗浄装置における裏面洗浄を説明した図
【図５】別実施例を説明するブロック図
【符号の説明】
１０…塗布装置、１１…カップ、１２…スリットノズル、１３…開口、１４…チャック、１５…塗膜、１５'…被膜、２０…ベーク装置、２１…ホットプレート、２２…カバー、３０…冷却装置、４０…洗浄装置、４１、４２…リンス液噴出ノズル、５０…レール、６０…トレイ、６１…凹部、６２…開口、Ｗ…板状被処理物。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a coating method and a coating apparatus for forming a coating on the surface of a plate-like workpiece such as a glass substrate or a semiconductor wafer, and further relates to a coating forming method and a coating forming apparatus incorporating the coating method and the coating apparatus.
[0002]
[Prior art]
As a method for forming a resist film or an SOG film on the surface of a plate-like workpiece such as a glass substrate or a semiconductor wafer, there are a spin coating method and a slit nozzle method.
[0003]
The spin coating method is a method in which a plate-like workpiece is rotated at a high speed with a spinner, and the coating solution dropped on the center of the plate-like workpiece is diffused by centrifugal force, and is disclosed in, for example, Japanese Patent Laid-Open No. 3-56163. Yes. In particular, in this prior art, a concave portion into which a plate-like workpiece is fitted is formed on the upper surface of the spinner head.
[0004]
Further, the slit nozzle method is disclosed in US Pat. No. 4,696,885 and the like, and the coating liquid is applied from the slit nozzle having the same width as the plate-like object to be processed to the plate-like object. In this method, a coating film is formed in a predetermined range by being moved relatively while dropping in a curtain shape.
[0005]
[Problems to be solved by the invention]
In the spin coating method, the amount of the coating solution involved in film formation is as small as about 5% of the supplied coating solution, and most of it is scattered by centrifugal force. There is also a problem that a thick film cannot be obtained.
Further, although the thickness of the plate-like object to be processed is increased, the thickness thereof is hardly changed, so that the plate-like object to be processed is bent by its own weight when the plate-like object is conveyed.
[0006]
According to the slit nozzle method, the waste of the coating liquid can be reduced and the thickness of the coating can be increased. However, in the slit nozzle method, there is a problem that the film thickness at the application start position and the application end position becomes extremely thick as compared with other parts due to the influence of the surface tension.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the film forming method according to the present invention is characterized by using a tray. A concave portion is formed in the tray, and when the plate-like workpiece is fitted into the concave portion, the surface of the tray and the surface of the plate-like workpiece are substantially flush with each other. Then, in this state, application is performed using a slit nozzle so that the application start position and the application end position are on the tray surface off the end of the plate-like workpiece.
[0008]
With such a configuration, the start and end of the coating film are continuously formed between the tray surface and the surface of the plate-like object to be processed, so that the film thickness may increase at the end of the plate-like object to be processed. The coating film having a uniform thickness is formed over the entire surface of the plate-like object.
Furthermore, the bending by the dead weight of the plate-shaped to-be-processed object produced at the time of conveyance etc. can be prevented by inserting in a tray.
[0009]
According to a first aspect of the present invention, there is provided a method for forming a film, comprising: a tray formed with a recess having a similar shape slightly larger than a planar shape of a plate-like workpiece and having a depth equal to or slightly shallower than the plate-like workpiece. In a state where the processing object is disposed so as to be movable, and a coating device, a baking device, a cooling device, and a cleaning device are provided along the transportation line, and the plate-like workpiece is fitted in the concave portion of the tray. Then, the plate-like object to be processed is fed together with the tray in the order of the coating device, the baking device, the cooling device, and the cleaning device, and processed by each device, thereby forming a film on the surface of the plate-like object.
According to a second aspect of the present invention, there is provided a film forming method comprising: forming a tray in which a recess having a similar shape slightly larger than a planar shape of the plate-like object to be processed and having a depth equal to or slightly shallower than the plate-like object to be processed; It is arranged movably on the transfer line of the object to be processed, and a coating device and a heating device are provided along the transfer line, and the plate-like object to be processed is fitted in the recess of the tray. The object to be processed is fed in the order of the coating device and the heating device and processed by each device. Thereafter, the plate-shaped material is removed from the tray, and the tray is subjected to cleaning treatment and temperature control processing, and then the location of the coating device. The plate-like object to be processed removed from the tray was subjected to a cooling process, a cleaning process, and a drying process.
[0010]
It is put in the tray until the heat treatment and the cooling treatment are completed, that is, until the liquid coating film becomes a solid coating film. After solidifying, the coating film at the end portion is cut off with a cleaning device (edge rinse) to obtain a coating film whose edge thickness is the same as that at the central portion.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is an overall configuration diagram of a coating film forming apparatus incorporating a coating apparatus according to the present invention. The coating film forming apparatus is a coating apparatus 10, a baking apparatus 20, The cooling device 30 and the cleaning device 40 are arranged, a rail 50 is provided between these devices, and the plate-like workpiece W fitted into the tray 60 is conveyed on the rail 50. A belt conveyor may be used instead of the rail 50.
[0012]
That is, the tray 60 is commonly used in all apparatuses. The structure of the tray 60 will be described according to the structure of the coating apparatus 10 with reference to FIG.
[0013]
In the coating apparatus 10, a tray 60 is placed in a cup 11, and a slit nozzle 12 is provided above the tray 60. The planar shape of the cup 11 and the tray 60 is matched to the shape of the plate-like workpiece W. When the plate-like workpiece W is a glass substrate, it is rectangular or square, and the plate-like workpiece W is a semiconductor wafer. In some cases, it is circular.
[0014]
A recess 61 is formed on the upper surface of the tray 60. The planar shape of the recess 61 is slightly larger than the plate-shaped workpiece W, and the plate-shaped workpiece W and the inner surface of the recess 61 are in a state where the plate-shaped workpiece W is fitted in the recess 61. A gap of about 0.05 mm is formed between them. Further, the depth of the recess 61 is equal to or slightly shallower than the thickness of the plate-like workpiece W.
[0015]
Further, openings 13 and 62 are formed in the central portions of the cup 11 and the tray 60, and the chuck 14 faces the openings 13 and 62. The chuck 14 is raised above the tray 60, the lower surface of the positioned plate-like workpiece W is vacuumed or electrostatically adsorbed, and then the chuck 14 is lowered, so that the plate-like workpiece is processed as described above. W fits into the recess 61. At this time, the surface of the plate-like workpiece W and the surface of the tray 60 are substantially flush.
[0016]
On the other hand, the slit nozzle 12 can be horizontally moved back and forth with a certain distance from the upper surface of the tray 60, and the movement start position, that is, the application start position, and the movement stop position, that is, the application end position, as shown in FIG. The end of the workpiece W is extended to the surface of the tray 60 that has been removed. As a result, the coating film 15 is formed up to a portion slightly protruding the end portion of the plate-like workpiece W.
At this time, the application means is not limited to the slit nozzle, and it goes without saying that an applicator, a doctor blade, or the like may be used. Furthermore, you may squeeze after application | coating or at the time of application | coating.
[0017]
Next, the plate-like workpiece W on which the coating film 15 is formed is conveyed to the baking device 20 through the rail 50 while being fitted in the tray 60. The transfer of the tray 60 from the cup 11 of the coating apparatus 10 onto the rail 50 is performed by a robot or the like.
[0018]
As shown in FIG. 3, a hot plate 21 and a cylindrical cover 22 are provided in the baking apparatus 20 so as to surround the hot plate 21. Both the hot plate 21 and the cover 22 can be moved up and down.
[0019]
By heating the coating film 15 in the baking apparatus 20 described above, the liquid coating film is solidified into a coating film. After heating, it is cooled in the cooling device 30. Since only the cool plate is disposed in the cooling device 30 instead of the hot plate, and the others are the same as the baking device 20, the description thereof is omitted.
[0020]
As shown in FIG. 4, upper and lower nozzles 41 and 42 for ejecting a rinsing liquid (cleaning liquid) are disposed in the cleaning device 40.
As shown in FIG. 4A, the upper nozzle 41 jets the cleaning liquid obliquely toward the edge of the plate-like workpiece W, dissolves the edge of the coating 15 ′, and at the edge The thickened part is removed. Since the portion to be removed is at the boundary between the tray and the plate-like workpiece W or slightly on the tray, the remaining film thickness is the same as or slightly thinner than the thickness on the plate-like workpiece W. A uniform coating 15 'is formed over the entire surface of the object.
[0021]
Next, in the cleaning device 40, as shown in FIG. 4B, the chuck 43 is raised, and the lower nozzle 42 removes the coating liquid and the like adhering to the back surface of the edge portion of the plate-like workpiece W. The concave portion 61 of the tray 60 is also cleaned.
[0022]
Another embodiment of the film forming apparatus according to the present invention will be described below. FIG. 5 is a block diagram illustrating the flow of processing.
The plate-like workpiece W is taken out from the cassette case by the transport device and is fitted into the recess 61 formed on the tray 60 placed on the coating device 10. The applicator and the baking process are performed for the entire tray as it is. Thereafter, the plate-like workpiece W is removed from the tray 60, and the tray 60 is cleaned by a tray cleaning device, transported to a temperature control device, temperature-controlled, and then placed on the coating device 10, and then placed on the next. Wait until the plate-like workpiece W is fitted. The number of trays is appropriately increased or decreased according to the throughput. On the other hand, the plate-shaped workpiece W removed from the tray 60 is transported to the cooling device by the transport device, and after cooling, processing such as cleaning (edge rinse) and drying is performed and stored in the processed storage cassette case. It is done.
[0023]
As yet another embodiment, the plate-like workpiece W fitted in the recess 61 of the tray 60 is integrated with the tray 60 and stored in the storage cassette. It is also possible to carry out a variety of processes.
[0024]
【The invention's effect】
As described above, according to the present invention, a coating film having a uniform thickness can be formed on the entire surface of the plate-like workpiece, and a coating film obtained by subjecting this coating film to heat treatment, cooling treatment, and washing treatment. Also, it is possible to form a film having a uniform thickness without any rise at the edge.
Therefore, the present invention is suitable for forming a coating having a thickness of 20 μm or more necessary for the bump process, and it is also possible to form a uniform coating having a thickness of 100 μm.
Further, by performing all the processing while being placed on the tray, the plate-like workpiece W is not bent by its own weight.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of a film forming apparatus incorporating a coating apparatus according to the present invention. FIG. 2 is a cross-sectional view illustrating the structure of a coating apparatus. FIG. 3 is a cross-sectional view illustrating the structure of a baking apparatus. FIG. 5A is a diagram illustrating edge rinse in a cleaning apparatus, FIG. 5B is a diagram illustrating back surface cleaning in the cleaning apparatus. FIG. 5 is a block diagram illustrating another embodiment.
DESCRIPTION OF SYMBOLS 10 ... Coating device, 11 ... Cup, 12 ... Slit nozzle, 13 ... Opening, 14 ... Chuck, 15 ... Coating film, 15 '... Coating, 20 ... Baking device, 21 ... Hot plate, 22 ... Cover, 30 ... Cooling device , 40: Cleaning device, 41, 42: Rinsing liquid ejection nozzle, 50 ... Rail, 60 ... Tray, 61 ... Recess, 62 ... Opening, W ... Plate-shaped workpiece.

Claims

A tray that has a similar shape slightly larger than the planar shape of the plate-like object to be processed and that has a recessed portion whose depth is equal to or slightly shallower than that of the plate-like object to be processed is movably disposed on the conveyance line of the plate-like object to be processed In addition, a coating device, a bake device, a cooling device, and a cleaning device are provided along the transport line, and the plate-like object to be processed together with the tray is inserted into the concave portion of the tray. A coating film forming method, wherein a coating film is formed on a surface of a plate-like object by feeding in order of a coating device, a baking device, a cooling device, and a cleaning device, and processing with each device.

A tray that has a similar shape slightly larger than the planar shape of the plate-like object to be processed and that has a recessed portion whose depth is equal to or slightly shallower than that of the plate-like object to be processed is movably disposed on the conveyance line of the plate-like object to be processed In addition, a coating device and a heating device are provided along the transport line, and the plate-like workpiece is placed together with the tray in the state where the plate-like workpiece is fitted in the recess of the tray. Then, the plate-like workpieces are removed from the tray, and after the cleaning treatment and the temperature adjustment processing are performed on the tray, the tray is put on standby at the location of the coating device and removed from the tray. A method of forming a film, comprising subjecting a treated product to a cooling treatment, a washing treatment, and a drying treatment.