Aluminum molybdenum etching solution and preparation method and application thereof

Abstract

The invention discloses an aluminum molybdenum etching solution as well as a preparation method and application thereof, and relates to the technical field of etching agents. Comprising a solvent and functional components, and the functional components comprise fluoroantimonic acid, sorbic acid, 1-hydroxyethylidene-1, 1-diphosphonic acid, fluoride and sulfate. Two organic weak acid oxidants, namely 1-hydroxyethylidene-1, 1-diphosphonic acid and sorbic acid, are added into functional components, and fluoroantimonic acid is used as a main oxidant to oxidize two metals, namely molybdenum and aluminum, so that the relative etching rate is changed. Then, sorbic acid is used as an auxiliary oxidizing agent or a buffer system, and in the etching process, the sorbic acid can ionize hydrogen ions along with the change of time to adjust the etching speed. Through the combination of fluoroantimonic acid and sorbic acid, the phenomenon that the etching speeds of molybdenum and aluminum are inconsistent can be remarkably improved, indentation or trailing of a metal layer is avoided, the residual phenomenon in the reaction process is reduced in cooperation with the action of 1-hydroxyethylidene-1, 1-diphosphonic acid, fluoride and sulfate, and the product yield is increased.

Description

Technical Field

[0001] The present invention relates to the technical field of etching agents, and in particular to an aluminum-molybdenum etching solution and a preparation method and application thereof. Background Art

[0002] Thin film transistor liquid crystal display is a type of active matrix liquid crystal display, which is widely used in electronic devices such as televisions, computer monitors, mobile phones, tablet computers, etc. In the production process of the array substrate of the thin film transistor liquid crystal display, etching is an indispensable link, and the effect of etching has a significant impact on the performance of the array substrate. The array substrate of the existing thin film transistor liquid crystal display mostly has a molybdenum-aluminum multilayer structure. Due to the large difference in the performance of molybdenum and aluminum, during the etching process, the etching speed of molybdenum and aluminum is prone to be different, resulting in indentation or tailing of the metal layer; and / or the etching ability of molybdenum and aluminum is different, resulting in metal substance residue, affecting product quality.

[0003] In view of this, the present invention is proposed. Summary of the invention

[0004] The object of the present invention is to provide an aluminum-molybdenum etching solution and a preparation method and application thereof.

[0005] The present invention is achieved in that:

[0006] In a first aspect, the present invention provides an aluminum-molybdenum etching solution, comprising a solvent and a functional component, wherein the solvent is water.

[0007] Functional ingredients include fluoroantimonic acid, sorbic acid, hydroxyethylidene diphosphonic acid, fluoride and sulfate.

[0008] In a second aspect, the present invention provides a method for preparing an aluminum-molybdenum etching solution as described in any of the aforementioned embodiments, comprising uniformly mixing a solvent and a functional component.

[0009] In a third aspect, the present invention provides an application of an aluminum-molybdenum etching solution as in any one of the aforementioned embodiments or an aluminum-molybdenum etching solution prepared by the preparation method as in the aforementioned embodiments for etching in a metal layer structure containing aluminum and molybdenum.

[0010] Preferably, the etching method of the metal layer structure containing aluminum and molybdenum by the aluminum-molybdenum etching solution is a one-step etching.

[0011] Preferably, the metal layer structure containing aluminum and molybdenum includes a molybdenum-aluminum composite metal layer or a molybdenum-aluminum-molybdenum composite metal layer.

[0012] The present invention has the following beneficial effects:

[0013] The present invention provides an aluminum-molybdenum etching solution and a preparation method and application thereof. By adding two organic weak acid oxidants, hydroxyethylidene diphosphonic acid and sorbic acid, to the functional components, fluoroantimonic acid is used as the main oxidant to oxidize the two metals, molybdenum and aluminum, thereby changing their relative etching rates. Then, sorbic acid is used as an auxiliary oxidant or a buffer system. During the etching process, sorbic acid can ionize hydrogen ions to adjust the etching speed over time. The system acidity of the aluminum-molybdenum etching solution of the present invention is relatively weak, so the more hydrogen ions ionized by sorbic acid, the better the ability to adjust the etching speed. The combination of fluoroantimonic acid and sorbic acid can significantly improve the phenomenon of inconsistent etching speeds of molybdenum and aluminum, avoid indentation or tailing of the metal layer, cooperate with the effects of hydroxyethylidene diphosphonic acid, fluoride and sulfate to reduce the occurrence of residual phenomena during the reaction process, and improve the yield rate of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0015] Figure 1 The SEM cross-sectional view of the molybdenum-aluminum composite metal layer after etching with the aluminum-molybdenum etching solution provided in Example 2 of the present invention according to the method of Experimental Example 1;

[0016] Figure 2 The SEM cross-sectional view of the molybdenum-aluminum composite metal layer after etching with the aluminum-molybdenum etching solution provided in Comparative Example 6 of the present invention according to the method of Experimental Example 1;

[0017] Figure 3 The SEM cross-sectional view of the molybdenum-aluminum composite metal layer after etching with the aluminum-molybdenum etching solution provided in Example 2 of the present invention according to the method of Experimental Example 1;

[0018] Figure 4 This is a SEM cross-sectional view of the molybdenum-aluminum composite metal layer after etching with the aluminum-molybdenum etching solution provided in Comparative Example 5 of the present invention according to the method of Experimental Example 1. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0020] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0021] In a first aspect, the present invention provides an aluminum-molybdenum etching solution, comprising a solvent and a functional component, wherein the solvent is water.

[0022] Functional ingredients include fluoroantimonic acid, sorbic acid, hydroxyethylidene diphosphonic acid, fluoride and sulfate.

[0023] At present, in the preparation process of the array substrate of the thin film transistor liquid crystal display, the etching process of the aluminum-molybdenum composite metal layer has a large difference in the etching rate of aluminum and molybdenum due to the large difference in the electrochemical properties and oxidation ability of aluminum and molybdenum, which may cause the metal molybdenum layer to indent or tail, making it difficult to form a good cone angle. Not only does the product obtained after etching have macroscopic defects, but after subsequent processing, it will also produce corresponding optical defects or cause the residue of the back layer material, affecting the product quality.

[0024] Therefore, the inventor proposes a new etching solution for etching a composite metal layer containing aluminum and molybdenum. The sorbic acid and hydroxyethylidene diphosphonic acid in the aluminum-molybdenum etching solution are both organic weak acids, wherein fluoroantimonic acid is used as a main oxidant to adjust the etching rates of the two metals, molybdenum and aluminum, thereby playing a major role in wet etching; sorbic acid is used as an auxiliary oxidant or a buffer system. During the etching process, sorbic acid can ionize hydrogen ions over time to adjust the etching rate. The aluminum-molybdenum etching solution with fluoroantimonic acid as the main oxidant has relatively weak acidity. Therefore, more hydrogen ions are ionized from sorbic acid, and the ability to adjust the etching rate is better, so that the aluminum-molybdenum etching solution system provided by the present invention can significantly improve the phenomenon that the etching rates of molybdenum and aluminum are inconsistent, and avoid indentation or tailing of the metal layer.

[0025] Further, hydroxyethylidene diphosphonic acid is added to the aluminum-molybdenum etching solution system to adjust the pH value of the molybdenum-aluminum etching solution, and the system of fluoroantimonic acid and sorbic acid can be further matched. If hydroxyethylidene diphosphonic acid is not added, the acidity of the system is too weak, the etching speed of aluminum and molybdenum is too slow, and metal residues may appear on the surface aluminum or molybdenum.

[0026] In addition, the multiple phosphate groups in hydroxyethylidene diphosphonic acid can complex with aluminum and molybdenum to form a stable substance, effectively dissolve the oxides on the metal surface, and assist in regulating the etching process. The hydrogen ions provided by fluoride and sulfate can produce hydrofluoric acid, which has very strong penetrability, thereby reducing the occurrence of residues during the reaction and improving the yield rate of the product. This system can not only remove the molybdenum and aluminum composite metal structure and etch to form a better profile, but also has no molybdenum and aluminum residues, and can also form a better cone angle, and the molybdenum layer has no indentation phenomenon.

[0027] In order to ensure the etching effect and facilitate the regulation of the etching speed of molybdenum and aluminum, in an optional embodiment, the functional components include, by mass percentage, 0.10wt% to 0.50wt% of fluoroantimonic acid, 5.0wt% to 20.0wt% of sorbic acid, 20.0wt% to 30.0wt% of hydroxyethylidene diphosphonic acid, 0.01wt% to 0.50wt% of fluoride and 5.0wt% to 10.0wt% of sulfate.

[0028] For example, in some embodiments, the mass percentage of fluoroantimonic acid in the aluminum-molybdenum etching solution can be any value in 0.10wt%, 0.20wt%, 0.30wt%, 0.40wt% or 0.50wt%, or a range value between any two of the above values ​​or any other point value within the range value. When the content of fluoroantimonic acid is too high, the etching rate is fast, which easily leads to a large difference in the etching speed of aluminum and molybdenum, affecting the precise control of the etching pattern; when the content of fluoroantimonic acid is too low, the etching rate is slow and the etching efficiency is low.

[0029] For example, in some embodiments, the mass percentage of sorbic acid in the aluminum-molybdenum etching solution can be 5.0wt%, 6.0wt%, 7.0wt%, 8.0wt%, 9.0wt%, 10.0wt%, 11.0wt%, 12.0wt%, 13.0wt%, 14.0wt%, 15.0wt%, 16.0wt%, 17.0wt%, 18.0wt%, 19.0wt% or 20.0wt% in any one of the values, or the range value between any two of the above values ​​or other arbitrary point values ​​within the range value. When the content of sorbic acid is too high, the acidity of the system is enhanced, the hydrogen ion content of sorbic acid ionization decreases, and the ability to regulate the etching speed decreases, which may cause the etching speed of aluminum and molybdenum to differ greatly; when the content of sorbic acid is too low, the acidity of the system is weak, it is difficult to adjust the etching speed, and it is not conducive to ensuring that the etching speeds of aluminum and molybdenum are consistent.

[0030] For example, in some embodiments, the mass percentage of hydroxyethylidene diphosphonic acid in the aluminum-molybdenum etching solution can be any of 20.0wt%, 21.0wt%, 22.0wt%, 23.0wt%, 24.0wt%, 25.0wt%, 26.0wt%, 27.0wt%, 28.0wt%, 29.0wt% or 30.0wt%, or a range value between any two of the above values ​​or any other point value within the range value. When the content of hydroxyethylidene diphosphonic acid is too high, it is easy to cause the etching rate difference of aluminum and molybdenum to increase; when the content of hydroxyethylidene diphosphonic acid is too low, the etching rate of aluminum and molybdenum is too slow, and metal residues may appear on the surface aluminum or molybdenum.

[0031] For example, in some embodiments, the mass percentage of fluoride in the aluminum-molybdenum etching solution can be any value in 0.01wt%, 0.05wt%, 0.10wt%, 0.15wt%, 0.20wt%, 0.25wt%, 0.30wt%, 0.35wt%, 0.40wt%, 0.45wt% or 0.50wt%, or the range value between any two of the above values ​​or other arbitrary point values ​​within the range value. When the content of fluoride is too high, it is easy to cause the penetration of the etching solution to increase, and it is difficult to accurately control the etching speed; when the content of fluoride is too low, it is easy to cause residual phenomenon in the etching process, affecting the yield rate of the product.

[0032] For example, in some embodiments, the mass percentage of sulfate in the aluminum-molybdenum etching solution can be any value of 5.0wt%, 6.0wt%, 7.0wt%, 8.0wt%, 9.0wt% or 10.0wt%, or a range value between any two of the above values ​​or any other point value within the range value. When the content of sulfate is too high, it is easy to cause the penetration of the etching solution to increase, and it is difficult to accurately control the etching speed; when the content of sulfate is too low, it is easy to cause residual phenomenon in the etching process, affecting the yield rate of the product.

[0033] Preferably, in terms of mass percentage, the functional ingredients include 0.10 wt% to 0.50 wt% of fluoroantimonic acid, 5.0 wt% to 10.0 wt% of sorbic acid, 20.0 wt% of hydroxyethylidene diphosphonic acid, 0.2 wt% of fluoride and 10.0 wt% of sulfate.

[0034] By controlling the proportion of functional components within the above range, the etching speed can be better adjusted to avoid indentation or tailing of the metal layer, and the main oxidation function of fluoroantimonic acid and the auxiliary oxidation function and buffering effect of sorbic acid can be better exerted to regulate the etching speed of molybdenum and aluminum.

[0035] The function of the above-mentioned functional components is to regulate the etching speed of aluminum and molybdenum, and to avoid metal residues in the etching process. Therefore, under the premise of ensuring the realization of the above-mentioned functions, in order to broaden the application scenarios of the aluminum-molybdenum etching solution, components with other effects can also be added to the system of the aluminum-molybdenum etching solution to cooperate with the system of the present invention, so as to achieve more and better etching effects of the aluminum-molybdenum etching solution.

[0036] In an optional embodiment, the solvent of the aluminum-molybdenum etching solution is water, more preferably deionized water.

[0037] In an optional embodiment, in order to avoid the addition of other ingredients affecting the etching rate of aluminum and molybdenum, the aluminum-molybdenum etching solution is composed of the following components, measured by mass percentage: 0.10wt%~0.50wt% of fluoroantimonic acid, 5.0wt%~20.0wt% of sorbic acid, 20.0wt%~30.0wt% of hydroxyethylidene diphosphonic acid, 0.01wt%~0.5wt% of fluoride, 5.0wt%~10.0wt% of sulfate, and the balance is water.

[0038] In order to further improve the etching effect of molybdenum and aluminum, preferably, it is composed of the following components, calculated by mass percentage: 0.1wt% to 0.5wt% of fluoroantimonic acid, 5.0wt% to 15.0wt% of sorbic acid, 20.0wt% to 25.0wt% of hydroxyethylidene diphosphonic acid, 0.1wt% to 0.3wt% of fluoride and 8.0wt% to 10.0wt% of sulfate, and the balance is water.

[0039] In an optional embodiment, the fluoride includes at least one of ammonium bifluoride, sodium fluoride, sodium bifluoride, potassium fluoride, potassium bifluoride, calcium fluoride and hydrofluoric acid; preferably ammonium bifluoride or hydrofluoric acid; more preferably ammonium bifluoride. By selecting the type of fluoride, the occurrence of residual phenomenon during the reaction can be reduced, and the other components in the system can be coordinated to achieve complete removal of the metal layer.

[0040] In an optional embodiment, the sulfate includes at least one of sodium sulfate, sodium bisulfate, potassium sulfate, potassium bisulfate, ammonium sulfate and ammonium bisulfate; preferably ammonium sulfate and potassium sulfate; more preferably ammonium sulfate. On the one hand, the sulfate can adjust the pH of the system to ensure smooth etching, while assisting in promoting the speed of aluminum and molybdenum; on the other hand, the sulfate can also reduce the residual molybdenum and improve the complete removal ability of the molybdenum layer.

[0041] In an optional embodiment, in order to ensure the etching effect of the aluminum-molybdenum etching solution and reduce metal etching residue, the fluoride in the above formula is ammonium bifluoride and the sulfate is ammonium sulfate.

[0042] In a second aspect, the present invention provides a method for preparing an aluminum-molybdenum etching solution as in any of the aforementioned embodiments, comprising uniformly mixing a solvent and a functional component. The etching solution provided by the present invention can ensure that each component can react with the metal layer of molybdenum and aluminum during the etching process by uniformly mixing each functional component and the solvent, thereby ensuring that the etching process proceeds smoothly, and at the same time, the etching speed of molybdenum and aluminum can be better adjusted to ensure the performance of the product after etching.

[0043] In an optional embodiment, in order to facilitate the uniform mixing of the components of the aluminum-molybdenum etching solution, fluoroantimonic acid, sorbic acid, hydroxyethylidene diphosphonic acid and a solvent are first mixed evenly, and then fluoride and sulfate are added and mixed evenly.

[0044] In a third aspect, the present invention provides an application of an aluminum-molybdenum etching solution as in any one of the aforementioned embodiments or an aluminum-molybdenum etching solution prepared by the preparation method as in the aforementioned embodiments for etching in a metal layer structure containing aluminum and molybdenum.

[0045] When etching a metal layer structure containing aluminum and molybdenum, the aluminum-molybdenum etching solution can regulate the etching rate of aluminum and molybdenum, avoid indentation or tailing of the metal layer, and effectively improve the etching yield of the metal layer structure containing aluminum and molybdenum.

[0046] Preferably, the etching method of the aluminum-molybdenum etching solution for the metal layer structure containing aluminum and molybdenum is one-step etching. The aluminum-molybdenum etching solution provided by the present invention can etch aluminum and molybdenum metals at the same time, and control the etching progress of the two metals to be basically similar, and one-step etching can produce a structure that meets the requirements.

[0047] Preferably, the metal layer structure containing aluminum and molybdenum includes a molybdenum-aluminum composite metal layer or a molybdenum-aluminum-molybdenum composite metal layer.

[0048] Example 1

[0049] The present embodiment provides an aluminum-molybdenum etching solution, which is composed of the following components, measured by mass percentage: 0.5wt% fluoroantimonic acid, 10.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0050] This embodiment also provides a method for preparing the above-mentioned aluminum-molybdenum etching solution, comprising first mixing fluoroantimonic acid, sorbic acid, hydroxyethylidene diphosphonic acid and deionized water in proportion, then adding ammonium bifluoride and ammonium sulfate, and mixing them in proportion to obtain an aluminum-molybdenum etching solution.

[0051] Example 2

[0052] The present embodiment provides an aluminum-molybdenum etching solution, which is composed of the following components, measured by mass percentage: 0.4wt% fluoroantimonic acid, 10.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0053] This embodiment also provides a method for preparing the above-mentioned aluminum-molybdenum etching solution, comprising first mixing fluoroantimonic acid, sorbic acid, hydroxyethylidene diphosphonic acid and deionized water in proportion, then adding ammonium bifluoride and ammonium sulfate, and mixing them in proportion to obtain an aluminum-molybdenum etching solution.

[0054] Example 3

[0055] This embodiment provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Embodiment 1.

[0056] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.3wt% fluoroantimonic acid, 10.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0057] Example 4

[0058] The present embodiment provides an aluminum-molybdenum etching solution, which is composed of the following components, measured by mass percentage: 0.2wt% fluoroantimonic acid, 10.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0059] This embodiment also provides a method for preparing the above-mentioned aluminum-molybdenum etching solution, comprising first mixing fluoroantimonic acid, sorbic acid, hydroxyethylidene diphosphonic acid and deionized water in proportion, then adding ammonium bifluoride and ammonium sulfate, and mixing them in proportion to obtain an aluminum-molybdenum etching solution.

[0060] Example 5

[0061] This embodiment provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Embodiment 1.

[0062] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.1wt% fluoroantimonic acid, 10.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0063] Example 6

[0064] This embodiment provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Embodiment 1.

[0065] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.3wt% fluoroantimonic acid, 5.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0066] Example 7

[0067] This embodiment provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Embodiment 1.

[0068] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.3wt% fluoroantimonic acid, 20.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0069] Example 8

[0070] This embodiment provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Embodiment 1.

[0071] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.3wt% fluoroantimonic acid, 10.0wt% sorbic acid, 30.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0072] Example 9

[0073] This embodiment provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Embodiment 1.

[0074] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.3wt% fluoroantimonic acid, 10.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% hydrofluoric acid, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0075] Example 10

[0076] This embodiment provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Embodiment 1.

[0077] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.3wt% fluoroantimonic acid, 10.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 5.0wt% ammonium sulfate, and the balance is deionized water.

[0078] Embodiment 11

[0079] This embodiment provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Embodiment 1.

[0080] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.3wt% fluoroantimonic acid, 10.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 5.0wt% potassium sulfate, and the balance is deionized water.

[0081] Comparative Example 1

[0082] This comparative example provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Example 1.

[0083] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.05wt% fluoroantimonic acid, 10.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0084] Comparative Example 2

[0085] This comparative example provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Example 1.

[0086] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.7wt% fluoroantimonic acid, 10.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0087] Comparative Example 3

[0088] This comparative example provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Example 1.

[0089] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.3wt% fluoroantimonic acid, 1.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0090] Comparative Example 4

[0091] This comparative example provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Example 1.

[0092] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.3wt% fluoroantimonic acid, 30.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0093] Comparative Example 5

[0094] This comparative example provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Example 1.

[0095] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.3wt% fluoroantimonic acid, 10.0wt% sorbic acid, 5.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium hydrogen fluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0096] Comparative Example 6

[0097] This comparative example provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Example 1.

[0098] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.3wt% fluoroantimonic acid, 10.0wt% sorbic acid, 40.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0099] Comparative Example 7

[0100] This comparative example provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Example 1.

[0101] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.3wt% fluoroantimonic acid, 10.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0102] Comparative Example 8

[0103] This comparative example provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Example 1.

[0104] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.3wt% fluoroantimonic acid, 10.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 1.0wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0105] Comparative Example 9

[0106] This comparative example provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Example 1.

[0107] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.3wt% fluoroantimonic acid, 10.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, and the balance is deionized water.

[0108] Comparative Example 10

[0109] This comparative example provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Example 1.

[0110] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.3wt% fluoroantimonic acid, 10.0wt% sorbic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 2.0wt% ammonium sulfate, and the balance is deionized water.

[0111] Comparative Example 11

[0112] This comparative example provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Example 1.

[0113] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.5wt% nitric acid, 10.0wt% acetic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0114] Comparative Example 12

[0115] This comparative example provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Example 1.

[0116] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.1wt% nitric acid, 10.0wt% acetic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0117] Comparative Example 13

[0118] This comparative example provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Example 1.

[0119] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.5wt% nitric acid, 5.0wt% acetic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0120] Comparative Example 14

[0121] This comparative example provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Example 1.

[0122] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.5wt% nitric acid, 20.0wt% acetic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0123] Comparative Example 15

[0124] This comparative example provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Example 1.

[0125] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 0.5wt% fluoroantimonic acid, 10.0wt% acetic acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0126] Comparative Example 16

[0127] This comparative example provides an aluminum-molybdenum etching solution, and the preparation method is the same as that of Example 1.

[0128] The aluminum-molybdenum etching solution is composed of the following components in percentage by mass: 5.0wt% sorbic acid, 1.0wt% nitric acid, 20.0wt% hydroxyethylidene diphosphonic acid, 0.2wt% ammonium bifluoride, 10.0wt% ammonium sulfate, and the balance is deionized water.

[0129] The formulas of the aluminum-molybdenum etching solutions of Examples 1 to 9 and Comparative Examples 1 to 16 provided by the present invention are shown in Table 1 below.

[0130] Table 1 Formula of aluminum-molybdenum etching solution provided in Examples and Comparative Examples

[0131]

[0132]

[0133]

[0134] Test Example 1

[0135] The aluminum-molybdenum etching solutions (10 L) provided in Examples 1 to 11 and Comparative Examples 1 to 16 were respectively used to etch the metal layer structures containing aluminum and molybdenum in the same batch using the same method, and the etching effect of each aluminum-molybdenum etching solution was detected by scanning electron microscopy, and the following results were obtained: Figure 1 to Figure 4 Results shown.

[0136] The etching method is as follows: Pour 10L of etching solution into a mini etching device, heat the etching solution to 40±0.1℃, then place a composite metal layer sample with molybdenum on the upper layer and aluminum on the lower layer in the etching solution to start etching, the time (EPD) for the metal etching of the aluminum-molybdenum two-layer metal layer to end is the aluminum-molybdenum EPD, and the total etching time is 1.5 times the aluminum-molybdenum EPD. After the etching is completed, take out the sample, rinse it with deionized water within 2 seconds, blow dry the surface moisture, and then place the molybdenum-aluminum composite metal layer under a scanning electron microscope for observation, and detect and evaluate the single-side etching distance, residue quantity, uniformity of the lines after etching, and molybdenum indentation of the molybdenum-aluminum composite metal layer etched by different aluminum-molybdenum etching solutions.

[0137] The single-side etching distance refers to the vertical distance between the sidewall of the etched pattern and the original masking layer pattern due to the lateral erosion of the material by the etchant during the etching process, and the unit is μm.

[0138] The number of residues refers to the number of all residues on the molybdenum-aluminum composite metal layer, in pieces.

[0139] The uniformity of the lines after etching refers to the difference in width of the lines at different positions after etching, and the unit is μm.

[0140] The molybdenum indentation refers to the distance that the molybdenum metal layer is indented relative to the aluminum metal layer, which is measured as CD and the unit is μm.

[0141] The evaluation criteria for the four etching effect parameters, namely, single-side etching distance, residue amount, uniformity of lines after etching, and molybdenum indentation, are shown in Table 2.

[0142] Table 2 Evaluation criteria for four parameters

[0143]

[0144]

[0145] According to the standards in Table 2, the etching effects of each aluminum-molybdenum etching solution provided in the embodiments and comparative examples were tested respectively, and the results shown in Table 3 were obtained.

[0146] Table 3 Etching effect of different aluminum-molybdenum etching solutions

[0147]

[0148]

[0149] As shown in Table 3, Comparative Example 1 reduces the amount of fluoroantimonic acid added, which significantly reduces the etching ability of the molybdenum-aluminum composite metal layer, and the single-side etching distance, the amount of residue, and the uniformity of the lines after etching are all deteriorated; while Comparative Example 2 increases the amount of fluoroantimonic acid added, and the etching speed of the metal layer is too fast, resulting in a significant increase in the single-side etching distance of the molybdenum-aluminum composite metal layer compared with Example 2. The molybdenum-aluminum composite metal layer obtained after etching can hardly be further processed to obtain a product of qualified quality, which seriously affects the yield rate of the product. Therefore, it is better to control the amount of fluoroantimonic acid added within the range of 0.1wt% to 0.5wt%.

[0150] Comparative Example 3 reduces the amount of sorbic acid added, and the single-side etching distance of the molybdenum-aluminum composite metal layer increases compared with Example 2, indicating that the sorbic acid content is low and the ability to control the etching rate of the metal layer is reduced. Comparative Example 4 increases the amount of sorbic acid added, and the single-side etching distance, the amount of residue, and the uniformity of the lines after etching of the metal layer are all worse than those of the embodiment, and the single-side etching distance is reduced compared with Example 2, indicating that the sorbic acid concentration is too high, the etching rate decreases, and it is not conducive to the etching rate adjustment of the metal layer. Therefore, it is better to control the amount of sorbic acid added within the range of 5.0wt% to 20.0wt%.

[0151] Comparative Example 5 reduces the addition of hydroxyethylidene diphosphonic acid, and the unilateral etching distance, the amount of residue and the uniformity of the lines after etching of the metal layer are all deteriorated, and the unilateral etching distance is reduced compared with Example 2, indicating that the content of hydroxyethylidene diphosphonic acid is too low and the etching rate decreases. Comparative Example 6 increases the addition of hydroxyethylidene diphosphonic acid, and the unilateral etching distance and the platinum indentation of the metal layer are increased compared with Example 2, indicating that the etching speed of the aluminum-molybdenum etching solution is too fast, which is not conducive to the etching rate control of the metal layer. Therefore, it is better to control the addition of hydroxyethylidene diphosphonic acid within the range of 20.0wt% to 30.0wt%.

[0152] In comparative example 7, no fluoride is added, so the etching residue of the molybdenum-aluminum composite metal layer increases. In comparative example 8, the amount of fluoride added increases, which leads to poor etching uniformity. Therefore, it is better to control the amount of fluoride added within the range of 0.01wt% to 0.5wt%.

[0153] In Comparative Example 9, no sulfate was added, and the etching uniformity of the molybdenum-aluminum composite metal layer became worse. In Comparative Example 10, the amount of sulfate added was reduced, and the etching uniformity of the molybdenum-aluminum composite metal layer was slightly better than that of Comparative Example 9, but the uniformity was still lower than that of Example 2. Therefore, it is better to control the addition amount of sulfate within the range of 5.0wt% to 10.0wt%.

[0154] Comparative Examples 11 to 16 respectively use nitric acid and / or acetic acid to replace the fluoroantimonic acid and / or sorbic acid in the embodiments of the present invention, and their molybdenum indentation amounts are all worse than those of the embodiments. Among them, Comparative Example 11 uses nitric acid to replace the fluoroantimonic acid in Example 1, and acetic acid to replace the sorbic acid in Example 1; Comparative Example 12 uses nitric acid to replace the fluoroantimonic acid in Example 3, and acetic acid to replace the sorbic acid in Example 3, but the aluminum-molybdenum etching solution of Comparative Examples 11 and 12 both etched the molybdenum-aluminum composite metal layer in a significant amount of molybdenum indentation. Comparative Examples 13 and 14 still use an oxidant system of nitric acid and acetic acid, and change the ratio of the two, but still cannot solve the problem of molybdenum indentation. Comparative Examples 15 and 16 respectively use an oxidant system of fluoroantimonic acid and acetic acid and an oxidant system of sorbic acid and nitric acid, but the phenomenon of molybdenum indentation is still very obvious.

[0155] The embodiment of the present invention uses fluoroantimonic acid as the main oxidant, and the organic weak acid oxidant system formed by cooperating with sorbic acid can significantly improve the phenomenon of molybdenum indentation. Figure 1 As shown, in the molybdenum-aluminum composite metal layer of Example 2, the molybdenum hardly retracts relative to the aluminum. After measurement, the amount of molybdenum retraction is 0.0357 μm. The molybdenum-aluminum composite metal layer is conducive to the smooth progress of subsequent processes and obtains products with excellent performance. Figure 1 It can also be seen that when the aluminum-molybdenum etching solution of Example 2 etches the molybdenum-aluminum composite metal layer, the single-side etching distance of the molybdenum-aluminum composite metal layer is 0.5216μm. According to the evaluation criteria of Table 2, the single-side etching distance level is excellent, and the etching angle is 63.99°, which is conducive to achieving accurate pattern depiction and avoiding the collapse of the upper layer caused by too large an angle. Figure 3 It can be seen that there is no etching residue on the surface of the molybdenum-aluminum composite metal layer etched by the aluminum-molybdenum etching solution provided in Example 2 of the present invention, and the product quality is better.

[0156] like Figure 2 As shown, the molybdenum-aluminum composite metal layer etched by the aluminum-molybdenum etching solution of Comparative Example 6 obviously has the molybdenum indentation of the upper layer. After measurement, the molybdenum indentation is 0.1885μm, which is too large, and the single-side etching distance is 1.2005μm, the single-side etching distance is also too large, and the etching angle is 73.25°, which easily leads to the collapse of the molybdenum in the upper layer, affecting the fine processing of the etching pattern. Therefore, the molybdenum-aluminum composite metal layer obtained by etching with the aluminum-molybdenum etching solution of Comparative Example 6 is difficult to further process into a product with better performance, and is generally scrapped. And from Figure 4It can be seen that etching residues appear on the surface of the molybdenum-aluminum composite metal layer etched by the aluminum-molybdenum etching solution provided in Comparative Example 5 of the present invention, and the product quality is poor.

[0157] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An aluminum-molybdenum etching solution, characterized in that: It comprises a solvent and a functional component, wherein the solvent is water; The functional ingredients include fluoroantimonic acid, sorbic acid, hydroxyethylidene diphosphonic acid, fluoride and sulfate.

2. The aluminum-molybdenum etching solution according to claim 1, characterized in that Calculated by mass percentage, the functional components include 0.10wt% to 0.50wt% of fluoroantimonic acid, 5.0wt% to 20.0wt% of sorbic acid, 20.0wt% to 30.0wt% of hydroxyethylidene diphosphonic acid, 0.01wt% to 0.50wt% of fluoride and 5.0wt% to 10.0wt% of sulfate.

3. The aluminum-molybdenum etching solution according to claim 1, characterized in that Calculated by mass percentage, the functional components include 0.10wt% to 0.50wt% of fluoroantimonic acid, 5.0wt% to 10.0wt% of sorbic acid, 20.0wt% of hydroxyethylidene diphosphonic acid, 0.2wt% of fluoride and 10.0wt% of sulfate.

4. The aluminum-molybdenum etching solution according to claim 2 or 3, characterized in that The fluoride includes at least one of ammonium bifluoride, sodium fluoride, sodium bifluoride, potassium fluoride, potassium bifluoride, calcium fluoride and hydrofluoric acid.

5. The aluminum-molybdenum etching solution according to claim 2 or 3, characterized in that: The sulfate includes at least one of sodium sulfate, sodium bisulfate, potassium sulfate, potassium bisulfate, ammonium sulfate and ammonium bisulfate.

6. The aluminum-molybdenum etching solution according to claim 3, characterized in that: The fluoride is ammonium bifluoride, and the sulfate is ammonium sulfate.

7. A method for preparing an aluminum-molybdenum etching solution as claimed in any one of claims 1 to 6, characterized in that: The process comprises uniformly mixing the solvent and the functional component.

8. The preparation method according to claim 7, characterized in that: The method comprises firstly mixing the fluoroantimonic acid, the sorbic acid, the hydroxyethylidene diphosphonic acid and the solvent evenly, and then adding the fluoride and the sulfate and mixing them evenly.

9. Use of the aluminum-molybdenum etching solution as claimed in any one of claims 1 to 6 or the aluminum-molybdenum etching solution prepared by the preparation method as claimed in claim 7 or 8 in etching a metal layer structure containing aluminum and molybdenum; The etching method of the aluminum-molybdenum etching solution on the metal layer structure containing aluminum and molybdenum is a one-step etching.

10. The use according to claim 9, characterized in that: The metal layer structure containing aluminum and molybdenum includes a molybdenum-aluminum composite metal layer or a molybdenum-aluminum-molybdenum composite metal layer.

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