!23〇817 ____________ 五、發明說明〇) ^明所屬之技術領域 口 本發明係提供一種製作金屬圖案的方法，尤指一種 可以有效減少蝕刻殘留物之製作金屬圖案的方法。 先前技術 ^ 在薄膜電晶體液晶顯示器面板的製程中，金屬圖案 •作之良窥對於液晶面板的品質影響甚大。舉例而言， 在液晶面板的製程中需進行數道黃光暨蝕刻程序，以分 別定義薄膜電晶體之閘極、源極/汲極以及接觸洞等堆疊 結構。為了提高後續介電沉積層之覆蓋能力，通常在定 義這些金屬圖案時，均會儘量避免在蝕刻製程中使金屬 圖案產生底切（undercut)的情況，以免蝕刻後之金屬碎 屬殘留於金屬圖案下方的孔隙，影響薄膜電晶體的電性 表現。因此目前業界於製作金屬圖案時係形成錐狀之側 壁結構’亦即使金屬圖案形成良好的平台（taper)形狀較 佳。 習知於玻璃基板上進行金屬層姓刻製程時，為了形 成良好的平台形狀，係採取浸泡式（D i p )溼蝕刻製程，/即 將玻璃基板以浸泡的方式浸泡在蝕刻液中，使姓刻液中 之化學藥劑與金屬薄膜產生化學反應，以去除未被遮罩 層覆蓋之金屬層，來定義玻璃基板上之金屬圖案。以产! 23〇817 ____________ V. Description of the invention 0) The technical field to which the invention belongs 口 The present invention provides a method for making a metal pattern, especially a method for making a metal pattern which can effectively reduce etching residues. Prior art ^ In the manufacturing process of thin film transistor liquid crystal display panels, metal patterns have a good impact on the quality of liquid crystal panels. For example, during the manufacturing process of the LCD panel, several yellow light and etching processes are required to define the stacked structures of the gate, source / drain, and contact hole of the thin film transistor, respectively. In order to improve the coverage of the subsequent dielectric deposition layer, usually when defining these metal patterns, undercutting of the metal pattern during the etching process is avoided as much as possible, so as to avoid metal fragments remaining in the metal pattern after the etching. The lower pores affect the electrical performance of the thin film transistor. Therefore, at present, in the industry, when forming a metal pattern, a tapered side wall structure is formed. Even if the metal pattern forms a good taper shape, it is better. It is known that when the metal layer name engraving process is performed on a glass substrate, in order to form a good platform shape, a dip (D ip) wet etching process is adopted, that is, the glass substrate is immersed in an etching solution in an immersion manner to make the name engraving. The chemical agent in the liquid reacts with the metal thin film to remove the metal layer that is not covered by the masking layer to define the metal pattern on the glass substrate. To produce
1230817 五、發明說明（2) 泡方式進行溼蝕刻，固然可以形成良好蝕刻形狀，然而 其缺點在於玻璃基板上的金屬圖案密度有疏有密，因此 極谷易產生負載效應（loading effect)，使得餘刻液中 化學藥劑與金屬層的反應不均，造成部分應去除掉之金 屬殘留在基板表面。尤其在金屬圖案線寬較狹窄處，由 於需要蝕刻掉大量之金屬，但因為蝕刻不均勻往往會導 致大量金屬殘留使基板產生缺陷，進而影響產品良率。 因此在玻璃基板的製作過程中，如何解決基板蝕刻 不均造成的金屬殘留問題，實為當前之重要課題。 發明内容 本發明之目的係提供一種液晶顯示器基板之金屬圖 案之蝕刻方法，以解決金屬殘留的問題。 在本發明之一較佳實施例中，該方法係利用一準分 子紫外光（e X c i m e r U V )於餘刻製程之前照射玻璃基板表 面金屬層，以降低金屬層表面張力，之後再進行一溼蝕 刻製程，去除部分該金屬層並形成金屬圖案。 由於本發明係利用一高能量光線，在進行蝕刻製程 之前先照射基板，使基板表面金屬層之表面張力降低， 故在進行蝕刻製程時，蝕刻液中之化學藥劑便不會因為1230817 V. Description of the invention (2) Although the wet etching method of the bubble method can form a good etching shape, the disadvantage is that the metal pattern density on the glass substrate is sparse and dense, so the valley is prone to loading effects, making The reaction between the chemical agent and the metal layer in the remaining etching solution is uneven, causing part of the metal to be removed to remain on the substrate surface. Especially in the place where the line width of the metal pattern is relatively narrow, a large amount of metal needs to be etched away, but uneven etching often causes a large amount of metal residue to cause defects on the substrate, which in turn affects the product yield. Therefore, in the process of manufacturing a glass substrate, how to solve the problem of metal residue caused by uneven etching of the substrate is an important issue at present. SUMMARY OF THE INVENTION An object of the present invention is to provide an etching method for a metal pattern of a liquid crystal display substrate to solve the problem of metal residue. In a preferred embodiment of the present invention, the method uses an excimer ultraviolet light (e X cimer UV) to irradiate the metal layer on the surface of the glass substrate before the remaining process to reduce the surface tension of the metal layer, and then performs a wet An etching process removes part of the metal layer and forms a metal pattern. Since the present invention uses a high-energy light, the substrate is irradiated before the etching process, so that the surface tension of the metal layer on the substrate surface is reduced. Therefore, during the etching process, the chemicals in the etching solution will not be caused by
1230817 五、發明說明（3) 表面張力過大，而與金屬表面產生過大之接觸角度，造 成蝕刻不均，產生金屬殘留物的情形，故可以有效提升 蝕刻製程的良率，改進習知金屬蝕刻製程的缺點。 實施方式 在本發明之較佳實施例中，首先於一玻璃基板上形 成一鉬/鋁/鉬複合金屬層，或是鉬/鋁合金金屬層，並以 一遮罩層覆蓋住該金屬層之部分表面，然後以一波長 1 72nm之準分子紫外光照射該玻璃基板表面，再進行一浸 泡式溼蝕刻，去除部分金屬層，以形成金屬圖案。同時 在本實施例中，經過準分子紫外光照射後所蝕刻出之金 屬圖案，具有一錐狀側璧結構，可形成良好的平台形 狀。 由於金屬圖案蝕刻製程中，採用浸泡式溼蝕刻製程 容易造成蝕刻不完全，其中一原因為基板上金屬層之表 面張力過大，致使在#刻過程中餘刻液中之化學藥劑與 金屬表面形成過大的接觸角度，而無法均勻蝕刻金屬， 特別是在基板上金屬線寬較狹窄處，如源極與汲極間的 空間、拉線區及孔洞的位置，由於此類區域需要蝕刻掉 大量之金屬，常會有金屬殘留物形成，因而影響基板品 質。1230817 V. Description of the invention (3) The surface tension is too large, and the contact angle with the metal surface is too large, resulting in uneven etching and metal residues, so it can effectively improve the yield of the etching process and improve the conventional metal etching process. Shortcomings. In a preferred embodiment of the present invention, a molybdenum / aluminum / molybdenum composite metal layer or a molybdenum / aluminum alloy metal layer is first formed on a glass substrate, and a metal layer is covered with a masking layer. Part of the surface is then irradiated with an excimer ultraviolet light having a wavelength of 1 72 nm to the surface of the glass substrate, and then a submerged wet etching is performed to remove a part of the metal layer to form a metal pattern. Meanwhile, in this embodiment, the metal pattern etched by the excimer ultraviolet light irradiation has a cone-shaped side ridge structure, which can form a good platform shape. In the metal pattern etching process, the immersion wet etching process is likely to cause incomplete etching. One of the reasons is that the surface tension of the metal layer on the substrate is too large, which causes the chemical agent in the remaining etching solution and the metal surface to form too large during the #etch Contact angle, and metal cannot be etched uniformly, especially where the metal line width on the substrate is narrow, such as the space between the source and the drain, the position of the pull line area, and the hole, because such areas need to etch away a large amount of metal , Metal residues often form, which affects the quality of the substrate.
1230817 五、發明說明（4) ^ -- 請參考表一，表一為在本發明較佳實施例中，基板 上之!目(鋁/錮複合金屬層或是鉬/|g合金金屬層以準分子 紫外f ^XCliner ultraviolet)照射前後之表面張力比較 表。 一可知，將基板分成九個區塊的情形下進行準 分子i外光照射，基板上金屬層大部分區塊之表面張力 均明顯下降，且平均下降程度達35%，由此可知以高能照 射來處理基板表面，確實能有效降低基板表面金屬層之 表面張力。 請 -先以 行#刻 圖中之 X、Y、 之區域 域中， 域更因 作。由 利用如 問題。 參考圖一，圖一為在本發明中之較佳實施例中， 準分子紫外光照射部分區域之玻璃基板後，再進 製私之基板檢視圖。其中基板被分成2 4個區域， 黑點表示金屬殘留造成之缺陷，且基板上A-Η、 Ζ為進行蝕刻製程前經由準分子紫外光照射處理過 。由圖一可知，經準分子紫外光照射處理過之區 出現的缺陷數目遠低於基板上其他區域，且S-W區 為蝕刻製程後被檢測出缺陷數過多而無法正常運 此可知在進行玻璃基板上金屬層之蝕刻製程時， 準分子紫外光之高能照射確實可解決金屬殘留的 除了在本發明較佳實例中使用之準分子紫外光外， 在本發明其他實施例中，可使用紫外光（u 11 r a ν i ο 1 e t)、 深紫外光（deep ultraviolet)、電聚（plasma)及常壓電1230817 V. Description of the invention (4) ^-Please refer to Table 1. In the preferred embodiment of the present invention, Table 1 shows the structure of the substrate (aluminum / rhenium composite metal layer or molybdenum / | g alloy metal layer to Comparison table of surface tension before and after excimer ultraviolet (F ^ XCliner ultraviolet) irradiation. It can be seen that when the substrate is divided into nine blocks and exposed to external light of excimer i, the surface tension of most blocks of the metal layer on the substrate is significantly reduced, and the average degree of decline is 35%. Treating the surface of the substrate can effectively reduce the surface tension of the metal layer on the substrate surface. Please-first use X #, Y, and Z in the figure. By using as questions. Reference is made to FIG. 1. FIG. 1 is an inspection view of a private substrate after an excimer ultraviolet light is irradiated on a glass substrate in a partial area in a preferred embodiment of the present invention. The substrate is divided into two or four areas. Black dots indicate defects caused by metal residues, and A-Η and Z on the substrate are treated by excimer ultraviolet light before the etching process. It can be seen from Figure 1 that the number of defects in the area treated by excimer ultraviolet light irradiation is much lower than other areas on the substrate, and the SW area is too many defects to be detected after the etching process. In the etching process of the upper metal layer, the high-energy irradiation of excimer ultraviolet light can indeed solve the metal residue. In addition to the excimer ultraviolet light used in the preferred embodiment of the present invention, in other embodiments of the present invention, ultraviolet light ( u 11 ra ν i ο 1 et), deep ultraviolet light, plasma, and ordinary piezoelectric
第7頁 1230817 五、發明說明（5) 漿（atmospheric pressure plasma)等高能照射光束來降 低玻璃基板表面張力，亦可達到與準分子紫外光類似的 效果，有效改善習知技術金屬殘留的問題。 相較於習知之玻璃基板金屬蝕刻技術，本發明在蝕 刻基板金屬圖案之前，先進行一高能照射降低基板上金 屬層$表面張力，使得在進行溼蝕刻製程時，蝕刻液之 化學藥劑能均勻地與金屬層表面薄膜進行蝕刻，有效改 善餘刻不均所造成的金屬殘留問題。 以上所述僅為本發明之較佳實施例，凡依本發明申 請專利範圍所作之均等變化與修飾，皆應屬本發明專利 之涵蓋範圍。Page 7 1230817 V. Description of the invention (5) High energy irradiation beams such as atmospheric pressure plasma can reduce the surface tension of glass substrates. It can also achieve similar effects to excimer ultraviolet light and effectively improve the problem of metal residues in conventional technologies. Compared with the conventional glass substrate metal etching technology, the present invention performs a high-energy irradiation to reduce the surface tension of the metal layer on the substrate before etching the metal pattern of the substrate, so that the chemical agent of the etching solution can be uniformly used in the wet etching process. Etching the thin film on the surface of the metal layer effectively improves the problem of metal residue caused by unevenness in the remaining time. The above description is only a preferred embodiment of the present invention, and any equivalent changes and modifications made in accordance with the scope of the patent application of the present invention shall fall within the scope of the patent of the present invention.
1230817 圖式簡單說明 圖式之簡單說明 圖一為一經準分子紫外光照射後之玻璃基板在蝕刻 製程後之檢視圖。 表一為本發明一玻璃基板利用準分子紫外光照射前 後之表面張力比較表。 I··! 1230817 區域 PI P2 P3 P4 P5 P6 P7 P8 P9 平均値 改良率 NO UV 6 . 4 9. 3 5 . 6 4 . 6 15 . 5 12 . 9 6.2 16. 1 7 . 7 9 . 37 35.5% UV 8 . 6 4 . 8 8 . 7 4 . 4 4.0 6.7 6.2 3.7 7.4 6. 06 表一1230817 Brief description of the drawings Brief description of the drawings Figure 1 is an inspection view of a glass substrate after the excimer ultraviolet light irradiation after the etching process. Table 1 is a comparison table of the surface tension before and after the glass substrate of the present invention is irradiated with excimer ultraviolet light. I ··! 1230817 Regional PI P2 P3 P4 P5 P6 P7 P8 P9 Average radon improvement rate NO UV 6. 4 9. 3 5. 6 4. 6 15. 5 12. 9 6.2 16. 1 7.. 7 9. 37 35.5 % UV 8. 6 4. 8 8. 7 4. 4 4.0 6.7 6.2 3.7 7.4 6. 06 Table 1