200935512 九、發明說明 【發明所屬之技術領域】 本發明是有關對平板面板顯示器（FPD )製造用的玻 璃基板等的基板實施乾蝕刻等的電漿處理之電漿處理裝置 及電漿處理方法。[Technical Field] The present invention relates to a plasma processing apparatus and a plasma processing method for performing plasma processing such as dry etching on a substrate such as a glass substrate for manufacturing a flat panel display (FPD).
I 【先前技術】 Q 例如’在FPD的製造製程或半導體裝置的製造製程中 ’對於玻璃基板或半導體晶圓等的基板進行乾蝕刻等的電 漿處理。如此的電漿處理大多是使用平行平板型的電漿處 理裝置。 平行平板型的電漿處理裝置是在反應室内將載置基板 的載置台與淋浴狀供給處理氣體的淋浴頭設成相對向，使 載置台具有作爲下部電極的機能，使淋浴頭具有作爲上部 電極的機能，藉由對該等的至少一方施加高頻電力，在該 G 等之間形成高頻電場，藉由此高頻電場來使處理氣體電漿 化而對玻璃基板進行電漿處理。 適用如此的平行平板型電漿處理裝置作爲電漿蝕刻裝 置時，可使用對上部電極的淋浴頭施加相對性頻率高的第 1高頻電力，對下部電極的載置台施加相對性頻率低的第 2高頻電力之上部下部施加型，或對下部電極的載置台施 加相對性頻率高的第1高頻電力及相對性頻率低的第2高 頻電力之下部雙頻施加型等，藉由如此的構成來適當地控 制電漿而進行良好的蝕刻處理。 -4- 200935512 可是，包含如此的上部下部施加型或下部雙頻施加型 的平行平板型電漿處理裝置，依放電條件，有可能在上部 電極的淋浴頭的氣體吐出孔内發生電弧放電，導致淋浴頭 (淋浴頭所保持的電極板）損傷而壽命變短，或造成裝置 缺陷。 就作爲解決的技術而言，在專利文獻1中提案對上部 電極施加相對性頻率低的第2高頻電力，加厚上部電極的 Q 電漿鞘層（plasma sheath )，阻礙電獎侵入淋浴頭的氣體 吐出孔内之技術。 然而，在此種的平行平板型電漿處理裝置中，並非只 有隨同如此的異常放電之問題，還有因爲附著於上部電極 的反應性生成物造成裝置的缺陷發生，成品率降低的問題 、或爲了除去如此的反應生成物，而縮短維修週期，生產 能力降低的問題。 〔專利文獻1〕特開2006-286791 ❹ 【發明內容】 (發明所欲解決的課題） 本發明是有鑑於該情事而硏發者，其目的是在於提供 一種不會發生異常放電所造成的問題，且可解消附著於電 極的反應生成物所引起的問題之平行平板型的電漿處理裝 置及電發處理方法。 (用以解決課題的手段） -5- 200935512 爲了解決上述課題，本發明的第1觀點是在於提供一 種電漿處理裝置，其特徵係具備： 處理室，其係收容被處理基板； 第1電極及第2電極，其係於上述處理室内相對向設 置； 第1高頻電力施加手段，其係對上述第1電極施加頻 率爲1 0MHz以上的第1高頻電力； φ 第2高頻電力施加手段，其係對上述第1電極施加頻 率爲2MHz以上10MHz未満的第2高頻電力； 第3高頻電力施加手段，其係對上述第2電極施加頻 率爲400kHz以上1.6MHz以下的高頻電力； 氣體供給機構，其係對上述處理室内供給電漿生成用 的處理氣體；及 排氣機構，其係對上述處理室進行排氣。 在上述第1觀點中，上述第1電極是支持被處理基板 e 的支持電極，上述第2電極可作爲對向於上述支持電極來 設置的對向電極。 又’最好上述第3高頻電力是具有不與上述第1及第 2高頻電力干擾的頻率。具體而言，最好上述第3高頻電 力的頻率是上述第1及第2高頻電力的頻率不會成爲其整 數倍的頻率。又’最好上述第3高頻電力是設定成可充分 地除去附著於上述第1或第2電極的附著物，附著物不會 附著的程度’且難以使上部電極消耗之功率。具體的功率 ’最好是0.009〜〇.〇55W/cm2的範圍。又，上述第3高頻 -6- 200935512 電力的更理想的頻率範圍’可舉600kHz以上1.0MHz以 下的範圍。 又，可更具備： 第1阻抗調整器，其係連接至上述第2電極，以對上 述第1高頻電力的頻率爲最適阻抗，對上述第2高頻電力 的頻率及上述第3頻率可成爲高阻抗的方式來調整阻抗； 及 0 第2阻抗調整器，其係連接至上述第2電極，以對上 述第2高頻電力的頻率爲最適阻抗，對上述第1高頻電力 的頻率及上述第3頻率可形成高阻抗的方式來調整阻抗。 此情況’亦可更具備第3阻抗調整器，其係連接至上 述處理室的側壁，以對上述第3高頻電力的頻率爲最適阻 抗，對上述第1高頻電力的頻率及上述第2頻率可形成高 阻抗的方式來調整阻抗。 可使用絕緣性的基板，作爲被處理基板。 Q 本發明的第2觀點是在於提供一種電漿處理方法，係 於收容被處理基板的處理室相對向設置第1電極及第2電 極，在該等之間形成高頻電場，藉由此高頻電場來使處理 氣體電漿化而對被處理體實施電漿處理之電漿處理方法， 其特徵爲： 對上述第1電極施加頻率爲10MHz以上的第1高頻 電力及頻率爲2MHz以上10MHz未満的第2高頻電力而生 成電漿， 對上述第2電極施加頻率爲400kHz以上1 ·6ΜΗζ以 200935512 下的第3高頻電力來濺射上述第1電極或上述第2電極的 表面而進行清潔。 在上述第2觀點中，與第1觀點同様，上述第丨電極 是支持被處理基板的支持電極，上述第2電極可作爲對向 於上述支持電極來設置的對向電極。 又，與第1觀點同樣，最好上述第3高頻電力是具有 不與上述第1及第2高頻電力干擾的頻率。具體而言，最 好上述第3高頻電力的頻率是上述第1及第2高頻電力的 頻率不會成爲其整數倍的頻率。又，最好上述第3高頻電 力是設定成可充分地除去附著於上述第1或第2電極的附 著物’附著物不會附著的程度，且難以使上部電極消耗之 功率。具體的功率，最好是0.009〜0.0 5 5W/cm2的範圍。 又，上述第 3高頻電力的更理想的頻率範圍，可舉 600kHz以上1.0MHz以下的範圍。 可使用絕緣性的基板，作爲被處理基板。 〔發明的效果〕 若根據本發明，則可藉由對第1電極施加第1及第2 高頻電力，擴大電漿鞘層，而難以產生異常放電，且可藉 由對第2電極施加第3高頻電力，利用其濺射效果來清潔 第1或第2電極、典型的是上部電極的表面。 【實施方式】 以下’參照圖面來說明有關本發明的實施形態。圖1 -8 - 200935512 是表示本發明的實施形態的電漿處理裝置的剖面圖。此電 漿處理裝置1是構成電漿蝕刻FPD用玻璃基板G的所定 膜之電容耦合型平行平板電漿蝕刻裝置。在此，FPD例如 可舉液晶顯示器 （LCD )、電致發光 （ElectroI [Prior Art] Q For example, in a manufacturing process of an FPD or a manufacturing process of a semiconductor device, a substrate such as a glass substrate or a semiconductor wafer is subjected to plasma treatment such as dry etching. Most of such plasma treatments use parallel plate type plasma processing devices. In the parallel plate type plasma processing apparatus, the mounting table on which the substrate is placed is placed in the reaction chamber so as to face the shower head in which the processing gas is supplied in the shower, and the mounting table has the function as the lower electrode, and the shower head has the upper electrode as the upper electrode. The function is to apply a high-frequency electric power between at least one of the above, and to form a high-frequency electric field between the G or the like, thereby plasma-treating the processing gas by the high-frequency electric field to perform plasma treatment on the glass substrate. When such a parallel plate type plasma processing apparatus is used as the plasma etching apparatus, the first high frequency power having a relatively high relative frequency can be applied to the shower head of the upper electrode, and the relative frequency of the lower electrode mounting stage can be used. (2) a high-frequency power upper portion is applied to the lower portion, or a first high-frequency power having a high relative frequency and a second high-frequency power lower-frequency double-frequency application type having a low relative frequency are applied to the mounting table of the lower electrode, and the like. The composition is appropriately controlled by the plasma to perform a good etching process. -4- 200935512 However, the parallel plate type plasma processing apparatus including such an upper lower application type or a lower dual frequency application type may cause arc discharge in the gas discharge hole of the shower head of the upper electrode depending on the discharge condition, resulting in arc discharge. The shower head (the electrode plate held by the shower head) is damaged and the life is shortened, or the device is defective. As a solution to the problem, Patent Document 1 proposes to apply a second high-frequency power having a low relative frequency to the upper electrode, and to thicken the Q plasma sheath of the upper electrode to prevent the electric prize from intruding into the shower head. The gas is spit out of the hole in the technique. However, in such a parallel plate type plasma processing apparatus, there is not only a problem of such abnormal discharge, but also a problem that the defect of the apparatus occurs due to the reaction product attached to the upper electrode, and the yield is lowered, or In order to remove such a reaction product, the maintenance cycle is shortened, and the productivity is lowered. [Patent Document 1] JP-A-2006-286791 ❹ [Summary of the Invention] The present invention has been made in view of the circumstances, and an object thereof is to provide a problem caused by abnormal discharge. Further, a parallel plate type plasma processing apparatus and an electric hair processing method which can solve the problems caused by the reaction product attached to the electrode can be eliminated. (Means for Solving the Problems) -5-200935512 In order to solve the above problems, a first aspect of the present invention provides a plasma processing apparatus including: a processing chamber for accommodating a substrate to be processed; and a first electrode And a second electrode that is disposed opposite to the processing chamber; and a first high-frequency power applying means that applies a first high-frequency power having a frequency of 10 MHz or more to the first electrode; φ a second high-frequency power application The second high frequency power is applied to the first electrode at a frequency of 2 MHz or more and 10 MHz, and the third high frequency power applying means applies a high frequency power having a frequency of 400 kHz or more and 1.6 MHz or less to the second electrode. a gas supply mechanism that supplies a processing gas for generating plasma into the processing chamber, and an exhaust mechanism that exhausts the processing chamber. In the above first aspect, the first electrode is a support electrode that supports the substrate to be processed e, and the second electrode is a counter electrode that is provided to face the support electrode. Further, it is preferable that the third high frequency power has a frequency that does not interfere with the first and second high frequency powers. Specifically, it is preferable that the frequency of the third high-frequency power is a frequency at which the frequencies of the first and second high-frequency powers do not become integral multiples. Further, it is preferable that the third high-frequency power is set so as to sufficiently remove the adhering matter adhering to the first or second electrode, and the adhering matter does not adhere to the state where it is difficult to consume the upper electrode. The specific power ' is preferably in the range of 0.009 to 〇. 〇 55 W/cm 2 . Further, the more preferable frequency range ′ of the third high frequency -6-200935512 power may be in a range of 600 kHz or more and 1.0 MHz or less. Furthermore, the first impedance adjuster may be connected to the second electrode to have an optimum impedance to the frequency of the first high frequency power, and to the frequency of the second high frequency power and the third frequency. a high impedance method to adjust the impedance; and a second impedance adjuster connected to the second electrode to have an optimum impedance to the frequency of the second high frequency power, and to the frequency of the first high frequency power and The third frequency described above can form a high impedance manner to adjust the impedance. In this case, a third impedance adjuster may be further provided, which is connected to the side wall of the processing chamber to have an optimum impedance to the frequency of the third high-frequency power, and to the frequency of the first high-frequency power and the second The frequency can form a high impedance way to adjust the impedance. An insulating substrate can be used as the substrate to be processed. According to a second aspect of the present invention, a plasma processing method is provided in which a first electrode and a second electrode are provided to face each other in a processing chamber in which a substrate to be processed is placed, and a high-frequency electric field is formed therebetween. A plasma processing method for plasma-treating a processing gas to perform plasma treatment on a target object, wherein the first high-frequency power having a frequency of 10 MHz or more and a frequency of 2 MHz or more and 10 MHz are applied to the first electrode. A plasma is generated by the second high-frequency power, and the surface of the first electrode or the second electrode is sputtered by the third high-frequency power of 200935512 at a frequency of 400 kHz or more to the second electrode. clean. According to the second aspect, in the same manner as the first aspect, the second electrode is a support electrode that supports the substrate to be processed, and the second electrode is a counter electrode that is provided to face the support electrode. Further, similarly to the first aspect, it is preferable that the third high frequency power has a frequency that does not interfere with the first and second high frequency power. Specifically, it is preferable that the frequency of the third high frequency power is a frequency at which the frequencies of the first and second high frequency powers do not become integer multiples. Further, it is preferable that the third high-frequency electric power is set so as to sufficiently remove the adhesion of the attachment attached to the first or second electrode, and it is difficult to consume the power of the upper electrode. The specific power is preferably in the range of 0.009 to 0.05 5 W/cm2. Further, a more preferable frequency range of the third high frequency power is a range of 600 kHz or more and 1.0 MHz or less. An insulating substrate can be used as the substrate to be processed. [Effects of the Invention] According to the present invention, by applying the first and second high-frequency electric power to the first electrode, the plasma sheath layer can be enlarged, and it is difficult to generate abnormal discharge, and the second electrode can be applied. 3 High-frequency power, using the sputtering effect to clean the surface of the first or second electrode, typically the upper electrode. [Embodiment] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Fig. 1-8 - 200935512 is a cross-sectional view showing a plasma processing apparatus according to an embodiment of the present invention. This plasma processing apparatus 1 is a capacitive coupling type parallel plate plasma etching apparatus which constitutes a predetermined film of a plasma etching FPD glass substrate G. Here, the FPD can be, for example, a liquid crystal display (LCD) or electroluminescence (Electro).
Luminescence ; EL)顯示器、電漿顯示器面板（PDP )等 〇 此電漿處理裝置1是具有由鋁所構成之形成角筒形狀 Q 的處理反應室2，其係例如表面被防蝕鋁處理（陽極氧化 處理）。在此處理反應室2内的底部設有用以載置被處理 基板的玻璃基板G之載置台3。 載置台3是隔著絕緣構件4來被支撐於處理反應室2 的底部，具有：用以吸附金屬製凸型的基材5及設於基材 5的凸部5a上的玻璃基板G之静電吸盤6、及設於静電吸 盤6及基材5的凸部5a的周圍，由絕緣性陶瓷例如氧化 鋁所構成之框狀的屏蔽環7、及設於基材5的周圍，由絕 〇 緣性陶瓷例如氧化鋁所構成之環狀的絕緣環8。静電吸盤 6是在由陶瓷等的電介體所構成的本體6a中埋設有電極 6b。在電極6b連接給電線18，在給電線18連接直流電源 1 9，藉由對電極6b施加來自直流電源1 9的直流電壓，可 利用庫倫力等的静電吸附力來吸附玻璃基板G。 以能夠貫通處理反應室2的底壁、絕緣構件4及載置 台3的方式，用以進行往其上之玻璃基板G的裝載及卸載 的昇降銷10可昇降地揷通。此昇降銷10是在搬送玻璃基 板G時，上昇至載置台3上方的搬送位置，除此以外的時 -9- 200935512 候是形成沈沒於載置台3内的狀態。 在載置台3的基材5連接用以供給第1高頻電力的給 電線12，在此給電線12連接第1整合器13及第1高頻電 源 14。從第 1高頻電源14供給 10MHz以上、例如 13.56MHz的第1高頻電力至載置台3的基材5。並且，在 基材5連接用以供給第2高頻電力的給電線15,在此給電 線15連接第2整合器16及第2高頻電源17。從第2高頻 φ 電源17供給2MHz以上10MHz未満、例如3·2ΜΗζ的第2 高頻電力至載置台3的基材5。因此，載置台3是具有作 爲下部電極的機能。 在上述載置台3的上方設有淋浴頭20，其係與該載置 台3平行對向而具有作爲上部電極的機能。淋浴頭2〇是 隔著絕緣構件29來被支撐於處理反應室2的上部，在内 部具有内部空間21，且在與載置台3對向的面形成有用以 吐出處理氣體的複數個氣體吐出孔22。此上部電極的淋浴 〇 頭20是與下部電極的載置台3 —起構成一對的平行平板 電極。 在淋浴頭20的上面設有氣體導入口 2.4，在此氣體導 入口 24連接處理氣體供給管25，此處理氣體供給管25是 被連接至處理氣體供給源28。並且，在處理氣體供給管 25介有開閉閥26及質量流控制器27。從處理氣體供給源 28供給電漿蝕刻用的處理氣體。處理氣體可使用鹵素系的 氣體、〇2氣體、Ar氣體等通常被使用於該領域的氣體。 並且，在上部電極的淋浴頭20連接用以供給第3高 -10- 200935512 頻電力的給電線31，在此給電線31連接第3整合器32 第3高頻電源33。從第3高頻電源33供給40 0 kHz以 l，6MHz以下、例如750kHz的第3高頻電力至上部電極 淋浴頭20。而且，第3高頻電力的頻率是與第1及第2 頻電力的頻率不干擾的頻率。亦即，上述第3高頻電力 頻率是不形成第1及第2高頻電力的頻率的整數分之一 相反的，第1及第2高頻電力的頻率是不形成第3高頻 φ 力的頻率的整數倍。 並且，在上部電極的淋浴頭20的上部外側，連接第 高頻電力用的第1阻抗調整器34、及第2高頻電力用的 2阻抗調整器3 5。 第1阻抗調整器34是串聯線圈36及可變電容器 來構成，以對第1高頻電力的頻率之阻抗的絶對値低， 其他高頻電力的頻率之阻抗的絶對値高的方式來設定電 常數，而使第1高頻電力會流動，第2及第3高頻電力 〇 乎不會流動。 第2阻抗調整器35是串聯線圈38及可變電容器 來構成，以對第2高頻電力的頻率之阻抗的絶對値低， 其他高頻電力的頻率之阻抗的絶對値高的方式來設定電 常數，而使第2高頻電力會流動，第1及第3高頻電力 乎不會流動。 在處理反應室2的底部形成有排氣管40，在此排氣 40連接排氣裝置41。排氣裝置41是具有渦輪分子泵等 真空栗，藉此構成可將處理反應室2内抽真空至所定的 及 上 的 高 的 〇 電 第 37 對 路 幾 39 對 路 幾 管 的 減 -11 - 200935512 壓環境。並且，在處理反應室2的側壁設有基板搬入出口 42，此基板搬入出口 42可藉由閘閥43來開閉。然後，可 在使該閘閥43形成開啓的狀態下藉由搬送裝置（未圖示 )來搬出入玻璃基板G。 此電漿處理裝置1的各構成部可藉由控制部50來控 制。此控制部50是具有：儲存有用以實施所定的控制之 控制程式等的程式儲存部、根據控制程式來實際控制各構 成部的控制器、及由鍵盤或顯示器等所構成的使用者介面 〇 具體而言，此控制部50是在於進行來自各高頻電源 的高頻電力的施加時序、該等的功率的控制、氣體的供給 及排氣的控制、閘閥及昇降銷等的驅動控制、往静電吸盤 的電壓供給控制等的控制。 其次，說明有關如此構成的電漿處理裝置1的處理動 作。首先，開啓閘閥43，利用搬送臂（未圖示）經由基板 搬入出口 42來將玻璃基板G搬入至處理反應室2内，載 置於載置台3的静電吸盤6上。此情況，是使昇降銷10 突出至上方來使位於支持位置，將搬送臂上的玻璃基板G 交接至昇降銷1〇上。然後，使昇降銷下降來將玻璃基 板G載置於載置台3的静電吸盤6上。 然後，關閉閘閥43，藉由排氣裝置4 1來將處理反應 室2内抽真空至所定的真空度。然後，從直流電源19施 加電壓至静電吸盤6的電極6b，藉此静電吸附玻璃基板G 。然後，開放閥26，從處理氣體供給源28使處理氣體藉 -12- 200935512 由質量流控制器27來一邊調整其流量一邊通過處理氣體 供給管25、氣體導入口 24來導入至淋浴頭20的内部空間 21，更通過吐出孔22來對基板G均一地吐出，一邊調節 排氣量一邊將處理反應室2内控制成所定壓力。 在此狀態下，對下部電極的載置台3的基材5，從第 1高頻電源14經由第1整合器13來供給10MHz以上、例 如13.5 6MHz的第1高頻電力，從第2高頻電源17經由第 φ 2整合器16來供給2MHz以上10MHz未満、例如3.2MHz 的第2高頻電力，使高頻電場產生於作爲下部電極的載置 台3與作爲上部電極的淋浴頭20之間，而生成處理氣體 的電漿，藉由此電漿來對玻璃基板G實施電漿蝕刻處理。 在此，之所以將第1高頻電力的頻率設爲10MHz以 上，是因爲電漿中的離子無法回應瞬間電場，爲發生負的 直流電壓（自偏壓）的頻帶，且電漿的高密度化形成可能 。又，之所以將第2高頻電力的頻率設爲2MHz以上 Q 10MHz未満，是爲了使離子更加速，提高基板表面反應的 促進、向異性蝕刻的效果，就未滿2MHz的低頻而言，電 漿中的離子會追隨電場的變化，不是自偏壓而是形成離子 衝突（濺射效應），恐有加深對基板的損傷之虞。 藉由如此對下部電極的載置台3供給第1高頻電力及 第2高頻電力來使該等重疊，可適當地控制電漿來進行良 好的蝕刻處理，但若繼續蝕刻，則反應生成物會附著於上 部電極的淋浴頭20表面，因此恐有裝置發生缺陷成品率 降低之虞。又，爲了不使如此裝置的缺陷發生，若縮短維 -13 - 200935512 修週期，則裝置操業率會降低。 基於防止如此的情況發生，本實施形態是對上部電極 的淋浴頭20，從第3高頻電源33經由第3整合器32來以 適當的功率施加更低頻率的400kHz以上1.6MHz以下、 例如75 OKHz的第3高頻電力。藉此可擴大上部電極的電 漿鞘層積極地提高鞘層電壓，藉由離子濺射來清潔附著於 上部電極的淋浴頭20的反應生成物（附著物）。 φ 之所以將第3高頻電力的頻率設在400kHz以上 1.6MHz以下的範圍，是因爲在此範圍可取得良好的濺射 力。以下說明有關確認此情況的實驗。在此，將下部電極 當作上部電極，進行測定施加各頻率的高頻電力後的下部 電極的自偏壓電壓（Vdc )，求取第3高頻電力的頻率與 濺射力的指標之自偏壓電壓（Vdc)的關係。將其結果顯 示於圖2。圖2是在橫軸取高頻電力的頻率，在縱軸取自 偏壓電壓（Vdc)，顯示有關該等的關係之圖表。由此圖 〇 表可知，Vdc是在 800kHz ( 0.8MHz )取極大値，在 400kHz ( 0.4MHz )〜1.6MHz的範圍可取得 600V以上的 高Vdc。更理想的範圍是600kHz (0·6ΜΗζ)〜1.0MHz的 範圍。由如此的頻率範圍選擇不與第1及第2高頻電力頻 率干擾的頻率。 其次，說明有關掌握第3高頻電力的功率與濺射力的 關係之實驗。在此是將切成3〇mmx30mrn的正方形之矽晶 圓樣品貼在上部電極（ 220cmx 25 0cm)之圖3所示的位置 ，對下部電極施加頻率13.56MHz、功率5kW的高頻電力 •14- 200935512 作爲第1高頻電力，施加頻率3.2MHz、功率5kW的高頻 電力作爲第2高頻電力，對上部電極使功率變化來施加頻 率750kHz的高頻電力作爲第3高頻電力，掌握矽晶圓樣 品的蝕刻速率。將其結果顯示於圖4。圖4是表示橫軸取 第3高頻電力（75 0kHz )的功率，縱軸取矽晶圓的蝕刻速 率的平均値之關係。如該圖所示，可知藉由施加第3高頻 電力，鈾刻速率會上昇，亦即附著物的濺射效果會提升。 Q 而且，確認蝕刻速率是第3高頻電力的功率越増加越上昇 〇 因此，爲了設定成可充分地除去反應生成物（附著物 )不會產生反應生成物的附著之功率，需要供給第3高頻 電力。但，若第3高頻電力的功率過大，則因爲上部電極 會消耗，所以需要設定成不會發生如此的情況之適當的功 率。第3高頻電力的功率較佳範圍是0.009〜0.055W/cm2 程度。 〇 利用此第3高頻電力之進行上部電極亦即淋浴頭20 的清潔之方法，在對玻璃基板G實施蝕刻處理時，是在第 1及第2高頻電力的施加後，稍微延遲施加第3高頻電力 ，即時除去附著於上部電極的淋浴頭20的反應生成物’ 在外觀上，可不使反應生成物附著。或亦可在施加第1及 第2高頻電力來對玻璃基板G進行所定片數的電漿處理後 ，例如在整批的交界等，載置虛擬基板的狀態下，或載置 台未有任何載置下施加第1及第2高頻電力，然後供給第 3高頻電力來進行上部電極的的淋浴頭20的清潔。另外’ -15- 200935512 亦可同時施加第1、第2高頻電力及第3高頻電力。又， 就別的方法而言，在只進行清潔時是可只供給第1高頻電 力及第3高頻電力。 其次，說明有關阻抗調整。 作爲本實施形態的對象之玻璃基板是一味追求大型化 ，形成一邊超過2m者，在對如此的大型玻璃基板進行電 漿處理時，因爲裝置也是形成大型，所以難以均一地形成 0 電漿，容易產生電漿的偏倚。於是，爲了防止如此的電漿 偏倚，如圖5的模式所示，在上部電極的淋浴頭20的上 部外側設置第1高頻電力用的第1阻抗調整器34及第2 高頻電力用的第2阻抗調整器35，第1阻抗調整器34是 使對第1高頻電力的阻抗最適化，僅第1高頻電力會流動 ，第2阻抗調整器35是使對第2高頻電力的阻抗最適化 ，僅第2高頻電力會流動，將第1高頻電力及第2高頻電 力引導至上部電極的淋浴頭20,而使該等高頻電力不會產 φ 生偏倚。亦即，第1阻抗調整器34及第2阻抗調整器35 除了阻抗調整機能以外還具有濾波器機能。 如此的阻抗調整器雖以往被使用，但在本實施形態爲 了將第3高頻電力供給至上部電極的淋浴頭20，第1及第 2阻抗調整器34，35除了上述機能以外，還需要以第3高 頻電力不會通過第1及第2阻抗調整器34，35來流至接 地側的方式設定第1及第2阻抗調整器34，35的電路常 數。亦即，如圖5所示，在第1阻抗調整器34是使對第1 高頻電力的阻抗最適化，以對第2及第3高頻電力之阻抗 -16- 200935512 的絶對値能夠變高的方式來設定電路常數，大致僅第1高 頻電力會流動，在第2阻抗調整器35是使對第2高頻電 力的阻抗最適化，以對第1及第3高頻電力之阻抗的絶對 値能夠變高的方式來設定電路常數，大致僅第2高頻電力 會流動。而且，第3高頻電力是如上述般不會通過第1及 第2阻抗調整器34，3 5來流至接地側，因此如圖5所示 ，流至處理反應室2的側壁部側。此情況，如圖6所示， 0 在處理反應室2的側壁設置第3阻抗調整器45，使對第3 高頻電力的阻抗最適化，以對第1及第2高頻電力之阻抗 的絶對値能夠變高的方式來設定電路常數，大致僅第2高 頻電力會流動，且亦可使第3高頻電力積極地流至側壁。 如此藉由第1及第2阻抗調整器34，35來進行阻抗 調整，第1及第2高頻電力可從下部電極的載置台3迅速 地流至上部電極的淋浴頭20，且第3高頻電力會流至處理 反應室2的側壁，因此不會有第3高頻電力對第1及第2 〇 高頻電力所生成的電漿造成不良影響的情況。 另外，本發明並非限於上述實施形態，亦可實施各種 的變形。例如，在上述實施形態是將第1及第2高頻電力 供給至下部電極，將第3高頻電力供給至上部電極，但亦 可將第1及第3高頻電力供給至上部電極，將第2高頻電 力供給至下部電極。又，上述實施形態是顯示有關將本發 明適用於絕緣體之FPD用的玻璃基板的電漿處理時，但並 非限於此，亦可對其他各種的基板適用。 200935512 【圖式簡單說明】 圖1是表示本發明之一實施形態的電漿處理裝置的剖 面圖。 圖2是表示第3高頻電力的頻率與Vdc的關係。 圖3是表示供以掌握第3高頻電力的功率與濺射力的 關係的實驗之上部電極的取樣位置。 圖4是表示第3高頻電力（75 0kHz )的功率與蝕刻速 率的平均値的關係。 圖5是用以說明阻抗調整器的模式圖。 圖6是表示設置第3高頻電力用的阻抗調整器的狀態 【主要元件符號說明】 1 :電漿處理裝置 2 :處理反應室 〇 3 :載置台 5 :基材 6 :静電吸盤 14 :第1高頻電源 17 :第2高頻電源 2〇 :淋洛頭 2 8 :處理氣體供給源 3 3 :第3高頻電源 3 4 ··第1阻抗調整器 -18- 200935512Luminescence; EL) display, plasma display panel (PDP), etc. The plasma processing apparatus 1 is a processing reaction chamber 2 having a corner tube shape Q formed of aluminum, for example, the surface is treated with alumite (anodizing) deal with). In this processing, the bottom of the reaction chamber 2 is provided with a mounting table 3 on which the glass substrate G of the substrate to be processed is placed. The mounting table 3 is supported by the bottom of the processing chamber 2 via the insulating member 4, and has a base material 5 for adsorbing a metal convex shape and a glass substrate G provided on the convex portion 5a of the base material 5. The electric chuck 6 and the frame-shaped shield ring 7 made of an insulating ceramic such as alumina are provided around the convex portion 5a of the electrostatic chuck 6 and the substrate 5, and are provided around the substrate 5. An annular insulating ring 8 made of an alumina ceramic such as alumina. The electrostatic chuck 6 is provided with an electrode 6b embedded in a body 6a made of a dielectric such as ceramic. The electrode 6b is connected to the electric wire 18, and the direct current power supply 1 is connected to the electric wire 18. The direct current voltage from the direct current power source 19 is applied to the counter electrode 6b, whereby the glass substrate G can be adsorbed by electrostatic adsorption force such as Coulomb force. The lift pins 10 for loading and unloading the glass substrate G thereon can be lifted and lowered so that the bottom wall of the reaction chamber 2, the insulating member 4, and the mounting table 3 can be penetrated. The lift pin 10 is a transport position that rises above the mounting table 3 when the glass substrate G is conveyed, and is immersed in the mounting table 3 at other times -9-200935512. The power supply line 12 for supplying the first high-frequency power is connected to the substrate 5 of the mounting table 3, and the first integrator 13 and the first high-frequency power source 14 are connected to the electric wire 12. The first high-frequency power of 10 MHz or more, for example, 13.56 MHz, is supplied from the first high-frequency power source 14 to the substrate 5 of the mounting table 3. Further, the base material 5 is connected to the power supply line 15 for supplying the second high frequency power, and the second integrated circuit 16 and the second high frequency power supply 17 are connected to the electric line 15. The second high-frequency power of 2 MHz or more and 10 MHz, for example, 3·2 満, is supplied from the second high-frequency φ power supply 17 to the substrate 5 of the mounting table 3. Therefore, the mounting table 3 has a function as a lower electrode. A shower head 20 is provided above the mounting table 3, and has a function as an upper electrode in parallel with the mounting table 3. The shower head 2 is supported by the upper portion of the processing chamber 2 via the insulating member 29, and has an internal space 21 therein, and a plurality of gas discharge holes for discharging the processing gas are formed on the surface facing the mounting table 3. twenty two. The shower head 20 of the upper electrode is a parallel plate electrode which forms a pair with the mounting table 3 of the lower electrode. A gas introduction port 2.4 is provided on the upper surface of the shower head 20, and a gas supply port 25 is connected to the gas inlet port 24, and the process gas supply pipe 25 is connected to the process gas supply source 28. Further, the process gas supply pipe 25 includes an on-off valve 26 and a mass flow controller 27. A processing gas for plasma etching is supplied from the processing gas supply source 28. As the processing gas, a gas such as a halogen-based gas, a helium gas, or an Ar gas which is generally used in the field can be used. Further, the shower head 20 of the upper electrode is connected to the power supply line 31 for supplying the third high -10-200935512 frequency power, and the third power amplifier 33 of the third integrator 32 is connected to the electric wire 31. The third high-frequency power of 40 kHz to 1,6 MHz or less, for example, 750 kHz, is supplied from the third high-frequency power source 33 to the upper electrode shower head 20. Further, the frequency of the third high frequency power is a frequency that does not interfere with the frequencies of the first and second frequency powers. In other words, the third high-frequency power frequency is opposite to an integer value of the frequency at which the first and second high-frequency powers are not formed, and the frequency of the first and second high-frequency powers does not form the third high-frequency φ force. An integer multiple of the frequency. Further, the first impedance adjuster 34 for the high-frequency power and the second impedance adjuster 35 for the second high-frequency power are connected to the outside of the upper portion of the shower head 20 of the upper electrode. The first impedance adjuster 34 is configured by a series coil 36 and a variable capacitor, and sets the electric power so that the impedance of the frequency of the first high-frequency power is absolutely low and the impedance of the frequency of the other high-frequency power is absolutely high. With the constant, the first high-frequency power flows, and the second and third high-frequency powers do not flow at all. The second impedance adjuster 35 is configured by a series coil 38 and a variable capacitor, and sets the electric power so that the impedance of the frequency of the second high-frequency power is absolutely low and the impedance of the frequency of the other high-frequency power is absolutely high. With the constant, the second high-frequency power flows, and the first and third high-frequency powers do not flow. An exhaust pipe 40 is formed at the bottom of the process chamber 2, and the exhaust gas 40 is connected to the exhaust device 41. The exhaust device 41 is provided with a vacuum pump such as a turbo molecular pump, thereby constituting a vacuum capable of evacuating the inside of the processing reaction chamber 2 to a predetermined high level. 200935512 Pressure environment. Further, a substrate loading port 42 is provided on the side wall of the processing chamber 2, and the substrate loading port 42 can be opened and closed by the gate valve 43. Then, the glass substrate G can be carried out by a transfer device (not shown) while the gate valve 43 is opened. The respective components of the plasma processing apparatus 1 can be controlled by the control unit 50. The control unit 50 includes a program storage unit that stores a control program for performing a predetermined control, a controller that actually controls each component based on the control program, and a user interface composed of a keyboard or a display. In addition, the control unit 50 is configured to perform the application of the high-frequency power from each of the high-frequency power sources, the control of the power, the control of the supply of the gas and the exhaust, the drive control of the gate valve and the lift pin, and the like. Control of voltage supply control of the electric chuck. Next, the processing operation of the plasma processing apparatus 1 thus constructed will be described. First, the gate valve 43 is opened, and the glass substrate G is carried into the processing reaction chamber 2 through the substrate carrying-in port 42 by a transfer arm (not shown), and is placed on the electrostatic chuck 6 of the mounting table 3. In this case, the lift pins 10 are protruded upward to be positioned at the support position, and the glass substrate G on the transfer arm is transferred to the lift pins 1A. Then, the lift pins are lowered to mount the glass substrate G on the electrostatic chuck 6 of the mounting table 3. Then, the gate valve 43 is closed, and the inside of the processing chamber 2 is evacuated to a predetermined degree of vacuum by the exhaust unit 41. Then, a voltage is applied from the DC power source 19 to the electrode 6b of the electrostatic chuck 6, whereby the glass substrate G is electrostatically adsorbed. Then, the valve 26 is opened, and the process gas is supplied from the processing gas supply source 28 to the shower head 20 through the process gas supply pipe 25 and the gas introduction port 24 while the flow rate is adjusted by the mass flow controller 27 by the mass flow controller 27. The internal space 21 is uniformly discharged to the substrate G through the discharge hole 22, and the inside of the processing reaction chamber 2 is controlled to a predetermined pressure while adjusting the amount of exhaust gas. In this state, the first high frequency power of 10 MHz or more, for example, 13.5 6 MHz, is supplied from the first high frequency power source 14 to the base material 5 of the mounting table 3 of the lower electrode via the first integrator 13 from the second high frequency. The power supply 17 supplies the second high frequency power of 2 MHz or more and 10 MHz, for example, 3.2 MHz, via the φ 2 integrator 16, and generates a high-frequency electric field between the mounting table 3 as the lower electrode and the shower head 20 as the upper electrode. On the other hand, a plasma of the processing gas is generated, and the glass substrate G is subjected to plasma etching treatment by the plasma. Here, the reason why the frequency of the first high-frequency power is 10 MHz or more is because the ions in the plasma cannot respond to the instantaneous electric field, and the frequency of the negative DC voltage (self-bias) occurs, and the high density of the plasma. Formation is possible. In addition, the frequency of the second high-frequency power is set to 2 MHz or more and Q 10 MHz is not required, so that the ions are accelerated more, and the effect of promoting the reaction on the surface of the substrate and the effect of the anisotropic etching are improved, and the low frequency of less than 2 MHz is used. The ions in the slurry follow the change of the electric field. Instead of self-biasing, they form ion collisions (sputtering effect), which may worsen the damage to the substrate. By supplying the first high-frequency power and the second high-frequency power to the mounting table 3 of the lower electrode in this manner, the plasma can be appropriately controlled to perform a good etching process. However, if the etching is continued, the reaction product is formed. It will adhere to the surface of the shower head 20 of the upper electrode, and there is a fear that the defective yield of the device will decrease. Moreover, in order not to cause the defects of such a device to occur, if the maintenance period of the dimension -13 - 200935512 is shortened, the operating rate of the device will be lowered. In order to prevent such a situation from occurring, in the present embodiment, the shower head 20 of the upper electrode is applied with a lower frequency of 400 kHz or more and 1.6 MHz or less, for example, 75 from the third high frequency power source 33 via the third integrator 32 at an appropriate power. The third high frequency power of OKHz. Thereby, the sheath layer of the upper electrode can be enlarged to positively increase the sheath voltage, and the reaction product (attachment) attached to the shower head 20 of the upper electrode can be cleaned by ion sputtering. φ The reason why the frequency of the third high-frequency power is set in the range of 400 kHz or more and 1.6 MHz or less is because a good sputtering force can be obtained in this range. The following describes the experiment to confirm this. Here, the lower electrode is used as the upper electrode, and the self-bias voltage (Vdc) of the lower electrode after the application of the high-frequency power of each frequency is measured, and the frequency of the third high-frequency power and the index of the sputtering force are obtained. The relationship between the bias voltage (Vdc). The results are shown in Fig. 2. Fig. 2 is a graph showing the frequency of high-frequency power on the horizontal axis and the bias voltage (Vdc) on the vertical axis, and a graph showing the relationship between them. As can be seen from the figure, Vdc is extremely large at 800 kHz (0.8 MHz), and a high Vdc of 600 V or higher can be obtained in the range of 400 kHz (0.4 MHz) to 1.6 MHz. A more desirable range is a range of 600 kHz (0·6 ΜΗζ) to 1.0 MHz. From such a frequency range, a frequency that does not interfere with the first and second high frequency power frequencies is selected. Next, an experiment for grasping the relationship between the power of the third high-frequency power and the sputtering power will be described. Here, a sample of a square wafer cut into 3 mm×30 mrn is attached to the position shown in FIG. 3 of the upper electrode (220 cm×250 cm), and a high frequency power of 13.56 MHz and a power of 5 kW is applied to the lower electrode. 200935512 As the first high-frequency power, a high-frequency power having a frequency of 3.2 MHz and a power of 5 kW is applied as the second high-frequency power, and the high-frequency power having a frequency of 750 kHz is applied to the upper electrode to change the power, and the third high-frequency power is used as the third high-frequency power. The etch rate of the round sample. The result is shown in Fig. 4. Fig. 4 is a diagram showing the relationship between the power of the third high frequency power (75 0 kHz) on the horizontal axis and the average 値 of the etching rate of the wafer on the vertical axis. As shown in the figure, it is understood that the uranium engraving rate is increased by the application of the third high-frequency electric power, that is, the sputtering effect of the deposit is enhanced. In addition, it is confirmed that the etch rate is increased as the power of the third high-frequency power increases. Therefore, in order to sufficiently remove the reaction product (adhesive), the power of the reaction product does not occur, and it is necessary to supply the third. High frequency power. However, if the power of the third high-frequency power is too large, since the upper electrode is consumed, it is necessary to set an appropriate power so that such a situation does not occur. The power of the third high frequency power is preferably in the range of 0.009 to 0.055 W/cm2. When the glass substrate G is etched by the method of cleaning the glass substrate G by the third high-frequency power, the method of cleaning the shower head 20 is slightly delayed after the application of the first and second high-frequency power. (3) The high-frequency electric power immediately removes the reaction product of the shower head 20 attached to the upper electrode, and the reaction product does not adhere to the appearance. Alternatively, after the first and second high-frequency powers are applied to perform a predetermined number of plasma treatment on the glass substrate G, for example, in a state where the dummy substrate is placed on the entire batch, or the mounting table does not have any The first and second high-frequency power are applied and the third high-frequency power is supplied to clean the shower head 20 of the upper electrode. In addition, the first and second high frequency power and the third high frequency power can be simultaneously applied to -15-200935512. Further, in the other method, only the first high-frequency power and the third high-frequency power can be supplied when cleaning is performed only. Next, explain the impedance adjustment. The glass substrate which is the object of the present embodiment is intended to be large-sized, and it is more than 2 m on one side. When such a large-sized glass substrate is subjected to plasma treatment, since the apparatus is also formed in a large size, it is difficult to uniformly form 0 plasma, which is easy. Produce a bias in the plasma. Then, in order to prevent such a plasma bias, as shown in the mode of FIG. 5, the first impedance adjuster 34 for the first high-frequency power and the second high-frequency power are provided on the outer side of the upper portion of the shower head 20 of the upper electrode. In the second impedance adjuster 35, the first impedance adjuster 34 optimizes the impedance of the first high-frequency power, and only the first high-frequency power flows, and the second impedance adjuster 35 makes the second high-frequency power. The impedance is optimized, and only the second high-frequency power flows, and the first high-frequency power and the second high-frequency power are guided to the shower head 20 of the upper electrode, and the high-frequency power is not biased. That is, the first impedance adjuster 34 and the second impedance adjuster 35 have a filter function in addition to the impedance adjustment function. Although such an impedance adjuster has been conventionally used, in the present embodiment, in order to supply the third high-frequency power to the shower head 20 of the upper electrode, the first and second impedance adjusters 34 and 35 need to be in addition to the above functions. The third high frequency power sets the circuit constants of the first and second impedance adjusters 34 and 35 so that the first and second impedance adjusters 34 and 35 flow to the ground side. In other words, as shown in FIG. 5, the impedance of the first high-frequency power is optimized in the first impedance adjuster 34, and the absolute impedance of the impedance of the second and third high-frequency powers is -16-200935512. When the circuit constant is set in a high manner, only the first high-frequency power flows, and the second impedance adjuster 35 optimizes the impedance of the second high-frequency power to the impedance of the first and third high-frequency power. The absolute constant 値 can be set to increase the circuit constant, and only the second high-frequency power flows. Further, since the third high-frequency power does not flow to the ground side by the first and second impedance adjusters 34 and 35 as described above, it flows to the side wall portion side of the processing chamber 2 as shown in Fig. 5 . In this case, as shown in FIG. 6, the third impedance adjuster 45 is provided on the side wall of the processing reaction chamber 2, and the impedance of the third high-frequency power is optimized to the impedance of the first and second high-frequency power. The circuit constant is set such that the absolute height can be increased, and only the second high-frequency power flows, and the third high-frequency power can be actively flowed to the side wall. In this way, the impedance adjustment is performed by the first and second impedance adjusters 34 and 35, and the first and second high-frequency power can be quickly flown from the mounting table 3 of the lower electrode to the shower head 20 of the upper electrode, and the third high The frequency power flows to the side wall of the processing chamber 2, so that the third high-frequency power does not adversely affect the plasma generated by the first and second high-frequency power. Further, the present invention is not limited to the above embodiment, and various modifications can be made. For example, in the above embodiment, the first and second high-frequency power are supplied to the lower electrode, and the third high-frequency power is supplied to the upper electrode. However, the first and third high-frequency power may be supplied to the upper electrode. The second high frequency power is supplied to the lower electrode. Further, in the above embodiment, the plasma treatment of the glass substrate for FPD in which the present invention is applied to an insulator is shown. However, the present invention is not limited thereto, and may be applied to various other substrates. [Brief Description of the Drawings] Fig. 1 is a cross-sectional view showing a plasma processing apparatus according to an embodiment of the present invention. FIG. 2 shows the relationship between the frequency of the third high frequency power and Vdc. Fig. 3 is a view showing a sampling position of an experimental upper electrode for grasping the relationship between the power of the third high-frequency power and the sputtering power. Fig. 4 is a graph showing the relationship between the power of the third high frequency power (75 0 kHz) and the average 値 of the etching rate. Fig. 5 is a schematic view for explaining an impedance adjuster. 6 is a view showing a state in which an impedance adjuster for a third high-frequency power is provided. [Description of main components and symbols] 1 : Plasma processing apparatus 2 : Process chamber 〇 3 : Mounting table 5 : Substrate 6 : Electrostatic chuck 14 : The first high-frequency power source 17: the second high-frequency power source 2〇: the shower head 2 8 : the processing gas supply source 3 3 : the third high-frequency power source 3 4 ·· the first impedance adjuster -18- 200935512
❹ 3 5 :第2阻抗調整器 4 5 :第3阻抗調整器 5 0 :控制部 G :玻璃基板 -19❹ 3 5 : 2nd impedance adjuster 4 5 : 3rd impedance adjuster 5 0 : Control part G : Glass substrate -19