經濟部智慧財產局員工消費合作社印製 414942 A7 B7 五、發明說明(1 ) 【產業上之利用領域】 本發明係有關於一種就積體電路製造等而言,採用聚 焦離子束的光罩以及施行分度線修正的光罩修正裝置之電 荷中和方法- 【習知技術】 近年來隨著半導體積體電路更進一步的微細化,就取 代採用雷射之缺陷修正裝置,所採用液體離子G a離子源 的聚焦離子束裝置,其利用微細的加工尺寸,製成光罩的 微小之白點和黑點的標準修正裝置。採用上述離子束的缺 陷修正裝置,於修正白點時,吸著在表面的原料氣體,只 會使得相當於離子束之處受到分解,而形成薄膜,且於修 正黑點時,於存有加速氣體下,只會在相當於離子束之處 進行蝕刻,而實現高加工精度。 習知所用的光罩或分度線,則是利用在石英玻璃等之 玻璃基板上,將C r和Μ 〇 S i等金屬膜,加以賤鍍而堆 積成遮光膜,且將光罩的圖案變換爲光透過率不同者。當 以G a +離子束加以照射時,會因其正電荷,在玻璃上引 發充電,即有難以觀察二次離子像,還會遭到靜電破壞光 罩之虞,因此必須將過剩的正電荷加以中和。雖將習知過 剩的正電荷予以中和,但欲覆蓋整個加工區域,卻是採用 束徑較大的電子束。 但此方法,會因光罩或分度線的圖案,在細光圈的離 子束的電流密度與寬度較寬的電子束的電流密度’產生局 本紙張尺度適用中國國家標準(CNS)A4規格(210 X 297公釐) 11 —^----111^-------1 -------線 .1 (請先閱讀背面之注意事項再填寫本頁) 41AU2 A7 _____B7 五、發明說明(2 ) 部性的電荷失衡。因此,無法利用圖案完成充分的電荷中 和’也會因充電的關係發生無法令缺陷修正得到必要的良 好圖像之情況。 【本發明欲解決之課題】 本發明之目的,乃針對如上所述的玻璃基板上的充電. ,而僅在必要之處照射細光圈之電流密度高的電子束,就 能大幅提升應用離子束的光罩修正裝置之電荷中和的效率 【用以解決課題之手段】 電荷中和所用的電子束,除掃描細光圈的光罩或分度 線外,還暫時將其二次電子像,讀入記憶裝置/由讀入的 二次電子像來決定電子束的照射位置,僅在必要之處,以 選擇性地高速掃描來照射細光圈之電流密度高的電子束。 如上所述,只對必要之處,以高速的掃描來照射細光 圏之電流密度高的電子束,就不會產生離子束與電子束的 局部電荷先衡*能有效地中和電荷。 【本發明之實施形態】 以下,根據第1圖說明有關本發明之—實施例。第1 圖係有關本發明之聚焦離子束裝置之斷面圖。 將自液體金屬G a離子源1被引出的離子束2,利用 電容式透鏡3 a和對物鏡3 b加以聚焦。將被聚焦的離子 本紙張尺度適用中國國家標準(CNS)A4規格(210 X 297公釐) (請先閱讀背面之注意事項再填寫本頁) -装 — 訂 --------^ 經濟部智慧財產局員工消費合作社印製 414942 A7 B7 五、發明說明(3 ) 束2,利用偏向電極4 ’在試料5的光罩或分度線上做掃 描。利用所聚焦的離子束2之照射所產生的二次離子6 ’ 會因傳輸光學系7的電界被聚焦’於聚焦之後’利用扇形 磁場8,導入被質量分離的各個檢測器9 °藉由令各檢測 器的信號強度,對應CRT上的1像素色調,與偏向電極 4的掃描同步而予顯示,藉以形成二次離子像。並由上述 二次離子像來指定應該修正的缺陷處。 指定實際的缺陷修正區域’是以光學式缺陷檢查裝置 等,在缺陷與辨識的試料上之座標,開始令聚焦離子束裝 置的步驟移動,藉以掃描聚焦其附近的離子束2 ’而讀取 二次離子來進行的。 缺陷修正則是一面由被設置在試料附近的氣槍18之 槍嘴,供給蝕刻所用的或是堆積所用的氣體’一面將聚焦 離子束2,在控制施加於偏向電極4的掃描信號而予指定 的修正位置,做重複的掃描照射而進行的。於黑點時’乃 利用氣體支援蝕刻效果,來除去多餘的遮光膜。於白點時 ,利用離子束來分解、堆積包含碳棒等遮光性物質的原料 氣體,以進行修正。 就上述之圖像和缺陷修正方面,當掃描所聚焦的離子 束2時,在試料5爲絕緣物的光罩或分度線的情形下’並 不會在絕緣物上引起充電,卻以電子束1 1準行電荷中和 。本發明特別是先將由電子源1〇被引出的電子束11’ 以電子光學系1 2,而在細光圏的偏向線圏1 3做掃描’ 將所產生的二次電子14,以二次電子檢測器1 5做檢測 本紙張尺度適用中國國家標準(CNS)A4規格(210 X 297公釐) (請先閱讀背面之注意事項再填寫本頁) 「裝--------訂---------M, 經濟部智慧財產局員工消費合作杜印製 414942 a? ―― B7 五、發明說明(4 ) ,並將二次電子像,暫時讀入記憶裝置1 6。接著將讀入 的二次電子像,利用圖像處理元件1 7做圖像處理,以決 (請先閱讀背面之注意事項再填寫本頁) 定應該照射電子束的區域。以後,只在如第2圖的斜線部 分之遮光膜2 1與玻璃部分2 2邊界之易充電的部分2 3 ,以高速的掃描來照射細光圈之電流密度高的電子束11 ,藉以緩和離子束2與電子束11的局部電荷失衡。 於以下說明上述之電荷中和的一連串操作之流程°就 試料5而言,會於形成在其表面的圖案膜,存有圖案缺陷 (白點、或黑點)。將包含試料5之至少缺陷的區域,, 利用聚焦的電子束1 1做掃描照射。將藉由以電子束1 1 的掃插照射所產生的二次電子1 4,讀入二次電子檢測器 1 5,使其圖像記憶在記憶裝置1 6。由所記憶的圖像, 將易充電的區域,利用圖像處理元件1 7做圖像處理,而 予抽出。將易於抽出的充電區域,一面選擇性地掃描電子 束,一面掃描包含缺陷區域所聚焦的離子束2,形成二次 離子像,於缺陷修正時,指定重複掃描照射離子束的區域 〇 經濟部智慧財產局員工消費合作社印製 其次,一面由氣槍1 8,將氣體吹噴至包含缺陷的區 域,一面將聚焦離子束2,只在指定的圖案缺陷區域,做 重複掃描照射。根據缺陷的種類,所吹噴的氣體會有所不 同。黑點的情形,爲蝕刻氣體,白點的情形,爲形成遮光. 膜的化合物氣體。與離子束照射同時將所聚焦的電子束 1 1,只在易抽出的充電區域,重複掃描照射,以有效率 地進行電荷中和。 本紙張尺度適用中國國家標準(CNS)A4規格(210 X 297公釐) 414942 A7 B7 五、發明說明(5 ) 若判斷爲修正缺陷時,即停止由氣槍1 8吹噴氣體。 然後’在包含缺陷的區域,掃描照射聚焦離子束2、或所 聚焦的電子束1 1 ’以確認修正加工狀況。即可在以上完 成缺陷修正。 【本發明之效果】 如以上說明’按本發明,就可在光罩或分度線之圖案 上,有、效率地中和電荷,因此很容易觀察二次電子像,不 必擔心靜電破壞。其結果,能作爲光罩修正裝置,並較習 知更廣泛地修正缺陷圖案,也能提升可靠性。 【圖面之簡單說明】 第1圖係實施本發明的聚焦離子束裝置之斷面圖。 第2圖係表示爲緩和電荷中和的失衡,做選擇性掃描 之區域圖。 【符號之說明】 1 液體金屬離子源 2 離子束 3 a 電容式透鏡 3 b 對物鏡 4 偏向電極 5 光罩或分度線 6 二次離子 本紙張尺度適用中國國家標準(CNS)A4規格(210 X 297公釐) i I --In--\·--- (請先閱讀背面之注意事項再填寫本頁) 訂----- 經濟部智慧財產局員工消費合作杜印製 經濟部智慧財產局員工消費合作社印製 414942 , A7 . ._B7 五、發明說明(6 ) 了 傳 輸 光 學 系 8 扇 形 磁 場 9 二 次 子 檢 測 器 1 0 電 子 源 1 1 電 子 束 1 2 電 子 光 學 系 1 3 偏 向 線 圈 1 4 二 次 電 子 1 5 —- 次 電 子 檢 測 器 1 6 記 憶 裝 置 1 7 圖 像 處 理 元 件 1 8 氣 槍 2 1 遮 光 膜 2 2 玻 璃 2 3 易 引 起充 電 之 區域 —..--------裝--------訂---------織 (請先閲讀背面之注意事項再填寫本頁) 本紙張尺度適用中國國家標準(CNS)A4規格(210 X 297公釐)Printed by the Employees ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 414942 A7 B7 V. Description of the invention (1) [Application fields in the industry] The present invention relates to a photomask using a focused ion beam in terms of integrated circuit manufacturing and the like, and Charge neutralization method of photomask correction device that performs index line correction-[Known Technology] In recent years, with the further miniaturization of semiconductor integrated circuits, laser defect correction devices have been replaced, and liquid ion G has been used. a Focused ion beam device of an ion source, which is a standard correction device for making tiny white and black points of a photomask using a fine processing size. By adopting the above-mentioned ion beam defect correction device, when correcting the white point, the raw material gas absorbed on the surface will only decompose the place equivalent to the ion beam to form a thin film, and when correcting the black point, there is acceleration. Under gas, etching is performed only at the place equivalent to the ion beam, and high processing accuracy is achieved. Conventionally used photomasks or graduation lines are formed on a glass substrate such as quartz glass by depositing metal films such as C r and MOS i to form a light-shielding film, and patterning the photomask. It is converted into one with different light transmittance. When irradiated with G a + ion beam, it will cause charging on the glass due to its positive charge. It may be difficult to observe the secondary ion image and may be damaged by static electricity. Therefore, the excess positive charge must be charged. Neutralize. Although the conventional excess of positive charges is neutralized, an electron beam with a large beam diameter is used to cover the entire processing area. However, due to the pattern of the reticle or graduation line, the current density of the ion beam in the narrow aperture and the current density of the wider electron beam will be generated. The paper size of this paper applies the Chinese National Standard (CNS) A4 specification ( 210 X 297 mm) 11 — ^ ---- 111 ^ ------- 1 ------- line. 1 (Please read the notes on the back before filling this page) 41AU2 A7 _____B7 5 2. Description of the invention (2) The partial charge imbalance. Therefore, the inability to complete sufficient charge neutralization with the pattern may cause the defect correction to obtain a necessary good image due to the charging relationship. [Problems to be Solved by the Invention] The purpose of the present invention is to charge the glass substrate as described above, and only by irradiating an electron beam with a high aperture current density at a narrow aperture where necessary, the application ion beam can be greatly improved. The efficiency of charge neutralization of the photomask correction device [means to solve the problem] The electron beam used for charge neutralization, in addition to scanning the aperture or graduation line of the small aperture, temporarily reads its secondary electron image and reads Into the memory device / The read position of the electron beam is determined by the read-in secondary electron image, and only where necessary, the electron beam with a high aperture current density at a narrow aperture is selectively scanned at high speed. As described above, only where necessary, high-speed scanning is used to irradiate the electron beam with a high current density in a thin light beam, and the local charge balance of the ion beam and the electron beam is not generated *, which can effectively neutralize the charge. [Embodiment of the present invention] Hereinafter, an embodiment of the present invention will be described with reference to Fig. 1. Fig. 1 is a sectional view of a focused ion beam apparatus according to the present invention. The ion beam 2 extracted from the liquid metal Ga ion source 1 is focused by the capacitive lens 3a and the objective lens 3b. The paper size of the ion to be focused is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) (Please read the precautions on the back before filling this page) -Packing-Order -------- ^ Printed by the Consumers 'Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 414942 A7 B7 V. Description of the invention (3) Beam 2, using the deflection electrode 4' to scan on the mask or graduation line of sample 5. The secondary ions 6 'generated by the irradiation of the focused ion beam 2 will be focused by the electrical boundary of the transmission optical system 7' after focusing ', using a fan-shaped magnetic field 8 to introduce each mass-separated detector 9 ° by ordering The signal intensity of each detector corresponds to the 1-pixel hue on the CRT and is displayed in synchronization with the scanning of the bias electrode 4, thereby forming a secondary ion image. The defects to be corrected are specified by the above secondary ion image. Specifying the actual defect correction area is based on the coordinates of the defect and identification sample on the optical defect inspection device, etc., and starts to move the step of focusing the ion beam device, so as to scan and focus the ion beam 2 in the vicinity to read two Secondary ions. Defect correction is specified by controlling the scanning signal applied to the deflection electrode 4 while focusing the ion beam 2 from the nozzle of the air gun 18 provided near the sample to supply the gas used for etching or stacking. The position is corrected by repeated scanning and irradiation. In the case of black spots', the gas-supported etching effect is used to remove the excess light-shielding film. At the white point, the ion beam is used to decompose and accumulate the source gas containing light-shielding substances such as carbon rods for correction. With regard to the above-mentioned image and defect correction, when the focused ion beam 2 is scanned, in the case that the sample 5 is a photomask or graduation line of an insulator, it does not cause charging on the insulator, but uses electrons The beam 11 is quasi-charge neutralized. In the present invention, firstly, the electron beam 11 ′ extracted from the electron source 10 is scanned by the electron optics 12 and the deflection line 313 of the thin beam 做 is scanned. Electronic detector 1 5 for testing This paper size is applicable to China National Standard (CNS) A4 specification (210 X 297 mm) (Please read the precautions on the back before filling this page) "Installation -------- Order --------- M, Consumer Cooperation of Intellectual Property Bureau of the Ministry of Economic Affairs, Du printed 414942 a? —— B7 V. Description of the invention (4), and temporarily read the secondary electronic image into the memory device 1 6 Next, use the image processing element 17 to perform the image processing of the read-in secondary electron image. (Please read the precautions on the back before filling this page.) Determine the area where the electron beam should be irradiated. In the future, only The light-shielding film 2 1 and the glass portion 2 2 in the oblique portion in FIG. 2 are easily charged portions 2 3 at the boundary, and the high-speed scanning is performed to irradiate the electron beam 11 with a high aperture current density at a small aperture, thereby relaxing the ion beam 2 and electrons. Local charge imbalance of beam 11. The flow of a series of operations of charge neutralization described above will be described below. In the case of sample 5, pattern defects (white spots or black spots) are deposited on the pattern film formed on the surface. The area containing at least the defects of sample 5 is scanned and irradiated with the focused electron beam 11. The secondary electrons 14 generated by irradiating with the scanning and insertion of the electron beam 11 are read into the secondary electron detector 15 and the image is stored in the memory device 16. From the stored image, The easy-to-charge areas are extracted by using the image processing element 17 for image processing. The easy-to-extract charging areas are scanned while selectively scanning the electron beam and scanning the ion beam 2 containing the focus of the defective area to form two The secondary ion image is designated to repeatedly scan the area where the ion beam is irradiated when the defect is corrected. It is printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. The gas is blown to the area containing the defect by an air gun 18, and the ion is focused. Beam 2 is repeatedly scanned and irradiated only in the designated pattern defect area. Depending on the type of defect, the gas blown will be different. The case of black spots is the etching gas, and the case of white spots is shaped. Shading. Film compound gas. Simultaneously scan and irradiate the focused electron beam 11 with the ion beam irradiation at the same time, in order to efficiently neutralize the charge in the charging area that is easy to extract. CNS) A4 specification (210 X 297 mm) 414942 A7 B7 V. Description of the invention (5) If it is determined that the defect is to be corrected, stop blowing gas from the air gun 18. Then, 'focus on the area where the defect is scanned and illuminated Beam 2 or focused electron beam 1 1 'to confirm the correction processing status. Defect correction can be completed above. [Effects of the present invention] As explained above, according to the present invention, it can be placed on the photomask or graduation line. On the pattern, the charge is effectively and efficiently neutralized, so it is easy to observe the secondary electron image without worrying about electrostatic damage. As a result, it can be used as a mask correction device, and the defect pattern can be corrected more widely than conventionally, and reliability can be improved. [Brief Description of Drawings] FIG. 1 is a sectional view of a focused ion beam device embodying the present invention. Figure 2 shows the area of selective scanning to alleviate the imbalance of charge neutralization. [Explanation of Symbols] 1 Liquid metal ion source 2 Ion beam 3 a Capacitive lens 3 b Opposite lens 4 Deflecting electrode 5 Photomask or graduation line 6 Secondary ions This paper applies Chinese National Standard (CNS) A4 specification (210 X 297 mm) i I --In-\ · --- (Please read the precautions on the back before filling this page) Order ----- The Intellectual Property Bureau of the Ministry of Economic Affairs, the consumer cooperation Du printed the wisdom of the Ministry of Economic Affairs Printed by the Consumer Cooperative of the Property Bureau 414942, A7 .._ B7 V. Description of the invention (6) The transmission optics 8 sector magnetic field 9 secondary detector 1 0 electron source 1 1 electron beam 1 2 electron optics 1 3 bias coil 1 4 Secondary electrons 1 5 —- Secondary electron detector 1 6 Memory device 1 7 Image processing element 1 8 Air gun 2 1 Light-shielding film 2 2 Glass 2 3 Areas prone to charge —..------- -Packing -------- Order --------- Weaving (Please read the notes on the back before filling this page) This paper size is applicable to China National Standard (CNS) A4 (210 X 297 Mm