KR101381482B1 - Etchant composition and method for fabricating metal pattern - Google Patents

Abstract

The present invention is capable of etching each of the first metal film including copper and the second metal film including molybdenum, and simultaneously etching liquid for batch wet etching the multiple films including the first metal film and the second metal film. Regarding the composition, with respect to the total weight of the composition, 0.1 to 7% by weight selected from the group consisting of nitric acid, sulfuric acid and mixtures thereof, 0.5 to 20% by weight of oxone, 0.01 to 1% by weight of fluorine-containing compound, It provides an etchant composition and a method of forming a metal pattern using the same, characterized in that the heterocyclic amine compound 0.01 to 1% by weight and the remaining amount of water to 100% in total.

Copper, copper alloy, molybdenum, etchant

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an etchant composition,

The etchant composition of the present invention relates to a wet etchant composition related to copper and molybdenum and a method of forming a metal pattern using the same, and includes a first single layer including copper and a second single layer including molybdenum in a flat panel display device. Provided are an etchant composition capable of etching each and simultaneously performing wet wet etching on multiple films including the first single film and the second single film, and a method of forming a metal pattern using the same.

Generally, the process of forming a metal wiring on a substrate in a semiconductor device and a flat panel display device is usually performed by a metal film forming process by sputtering, a photoresist coating process, a photoresist forming process in an optional region by exposure and development, And includes a cleaning process before and after the individual unit process, and the like.

The etching process refers to a process of leaving a metal film in a selective region using a photoresist mask, and typically, dry etching using plasma or wet etching using an etching solution is used.

In such a semiconductor device or a flat panel display device, a copper related film and a molybdenum related film have been studied as a wiring and are commercially available.

In addition, various etchant compositions have been proposed in order to form a copper-related film and a molybdenum power film using a wet etching method.

Initially, a mixed solution of phosphoric acid, nitric acid, acetic acid, a chlorinated compound and a fluorinated compound was used depending on the constitution conditions of the thin film. However, when the copper-molybdenum film is etched using the above mixed solutions, the galvanic phenomenon, that is, the etching speed of the upper copper is too fast, so that when the molybdenum film located at the bottom is etched, the copper is over- The phenomenon that does not remain appears. As a result, when the external driving voltage is applied, the resistance value inherent to copper can not be shown, which makes it difficult to apply to the process. In addition, the straightness of the wiring is not excellent in view of etching characteristics, and the taper angle is more than 90 degrees, which may cause problems in the subsequent process. Due to such a problem, there are many disadvantages in the practical process, and it is difficult to apply the mixed solutions to the copper-molybdenum film etching.

In addition, recently, the case of the mixed aqueous solution of the fruit has received much attention in the flat panel display. However, in the case of the above-mentioned hydrous mixed solution, the concentration changes with time, which causes a problem that affects the number of treatments, that is, the amount of the substrate to be etched. In more detail, in the case of the fruit juice mixture, the wet etching of copper causes the etched copper to be present in the fruit water, and when the amount becomes saturated and reaches its peak, a rapid temperature rise occurs. As a result, a large accident can be caused in the actual process, and the amount of the process is limited. In addition, in the case of an aqueous mixed solution, an auxiliary equipment is required to carry out the process, which raises a problem that the manufacturing cost is increased.

Accordingly, in order to solve such problems in this field, there is a need to develop a novel etching composition having no reaction with copper, which is a residue due to wet etching, and having excellent properties in etching.

Accordingly, in order to solve the above problems of the prior art, the present invention can etch the first single film containing copper and the second single film containing molybdenum, respectively, and at the same time the first single film and the first film It is an object of the present invention to provide an etching liquid composition capable of performing a batch wet etching of a multilayer including a single layer and a metal pattern forming method using the same. In addition, an object of the present invention is to provide an etching liquid composition excellent in etching characteristics and stability, and a metal pattern forming method using the same.

In order to achieve the above object, the etchant composition of the present invention is 0.1 to 7% by weight selected from the group consisting of nitric acid, sulfuric acid and mixtures thereof; Oxone 0.5-20 wt%; 0.01 to 1% by weight of a fluorine compound; 0.01-1 weight percent of heterocyclic amine compound; And it provides an etchant composition comprising the remaining amount of water to 100% total.

In addition, the present invention is any one or multiple of a first metal film containing copper, a second metal film containing molybdenum and a multiple film including the first metal film and the second metal film on the substrate. It provides a wiring forming method comprising the step of etching the first metal film, the second metal film and the multi-layer using the etchant composition.

The etchant composition of the present invention can etch a first single film comprising copper and a second single film comprising molybdenum, respectively, and at the same time collectively etching the multiple films comprising the first single film and the second single film There is an effect that can be. In addition, since the stability of the chemical solution is ensured in the process, there is no damage to the underlying film, uniform etching characteristics, application of a large area substrate, and etching property without damage to the equipment are provided.

The etchant composition of the present invention is capable of etching each of the first single film containing copper and the second single film containing molybdenum, and simultaneously etching the multiple films including the first single film and the second single film. It relates to an etchant composition.

The film used in the present invention is composed of a double film including a first single film including copper, a first single film including copper, and a second single film including molybdenum, wherein the double film is the second single film. The first single film is formed on the film. In addition, although the bilayer including the first single layer and the first single layer and the second single layer is used in the present invention, the present invention is not limited thereto.

Hereinafter, the present invention will be described in detail.

One selected from the group consisting of nitric acid, sulfuric acid and mixtures thereof included in the etchant composition of the present invention serves to oxidize copper and molybdenum. In addition, it reduces the residue generated during the etching process, and serves to improve the profile and taper angle of the etched metal pattern. In addition, the nitric acid (HNO ₃ ) or sulfuric acid (H ₂ SO ₄ ) may also play a role of controlling the etching rate.

One kind selected from the group consisting of nitric acid, sulfuric acid and mixtures thereof is contained in an amount of 0.1 to 7% by weight based on the total weight of the composition. As a result, desired etching characteristics cannot be obtained, and in the double layer including the first single layer including copper and the second single layer including molybdenum, the second single layer disposed below is not etched. In addition, when the content is more than 7% by weight, excessive etching of copper may occur, resulting in peeling off of the copper film, which is not suitable for use in the process.

Oxone included in the etchant composition of the present invention is a component that oxidizes copper, and is contained in an amount of 0.5 to 20 wt% based on the total weight of the composition. When the oxone is contained in less than 0.5% by weight, the etching rate of the copper is lowered or uneven etching occurs due to uneven etching, when the excess exceeds 20% by weight of copper occurs.

In the present invention, the fluorine-containing compound serves to oxidize molybdenum, to speed up the etching rate and to remove the etching residue.

The fluorine-containing compound is preferably a compound capable of dissociating into fluorine ions or polyatomic fluorine ions in solution, and is preferably selected from the group consisting of ammonium fluoride, sodium fluoride, potassium fluoride, sodium bifluoride and potassium bifluoride. Do.

The fluorine-containing compound is contained in 0.01 to 1% by weight based on the total weight of the composition. When the fluorine-containing compound contains less than 0.01% by weight, in the double layer including the first single layer including copper and the second single layer including molybdenum, the second single layer, which is a lower layer, is not etched or the substrate Partially molybdenum residues may form in the interior. In addition, if it exceeds 1% by weight, the underlayer is damaged. Here, the lower layer means a semiconductor substrate such as a glass substrate and a silicon oxide film, a silicon nitride film, amorphous silicon, polysilicon, doped amorphous silicon, doped polysilicon.

The heterocyclic amine compound contained in the etchant composition of the present invention is a component that controls the etching rate of the copper film. In addition, the non-covalent electron pair of the nitrogen atom in the heterocyclic ring of the heterocyclic amine compound binds to the copper to prevent re-adsorption of the organic contaminants left in the copper, so that the attack of copper can be minimized.

The heterocyclic amine compound is preferably selected from the group consisting of imidazole, aminotetrazole, pyrrolidine, pyrroline, pyrrole, indole, pyrazole, imidazole, pyrimidine, purine and pyridine.

 The heterocyclic amine compound is contained at 0.01 to 1% by weight based on the total weight of the composition. If the heterocyclic amine compound is contained in less than 0.01% by weight can not control the etching rate of the copper can be over-etched, if contained in more than 1% by weight the etching rate of copper is lowered process Etching time in the bed can be long, which can be a problem for productivity.

Water used in the present invention means deionized water and can be used for semiconductor processing, preferably water of 18 kW / cm or more.

The etchant composition of the present invention may further comprise at least one of an etch control agent, a surfactant, a sequestering agent, a corrosion inhibitor and a pH adjuster.

A method of forming a metal pattern by etching any one or more of a first single film containing copper, a second single film containing molybdenum, and multiple films thereof using the etchant composition of the present invention is specifically Forming one or more of a first single film comprising copper, a second single film comprising molybdenum and multiple films thereof on the substrate; Etching any one of the first single film, the second single film and their multiple films using the etchant composition of the present invention.

Here, the step (a) may include providing a substrate and forming one or a plurality of the first single layer, the second single layer, and the multiple layer on the substrate. The substrate may perform a conventional cleaning process, and the substrate may be a wafer, a glass substrate, a stainless steel substrate, a plastic substrate, or a quartz substrate. Forming the first single layer, the second single layer, and the multilayer on the substrate As a method, various methods known to those skilled in the art can be used, and it is preferable to form using a vacuum deposition method or a sputtering method.

In the step (b), a photoresist is formed on the first single layer, the second single layer, and the multi-layer, selectively exposing the photoresist using a mask, and exposing the exposed photoresist. After baking, the baked photoresist is developed to form a photoresist pattern. The first monolayer, the second monolayer, and the multilayer having the photoresist pattern formed thereon are etched using the etchant composition of the present invention to complete the metal pattern.

Such an etching process can be performed according to a method well known in the art, and examples thereof include a method of dipping, a method of spraying, and the like. During the etching process, the temperature of the etching solution may be in the range of 30 to 50 ° C., and the optimum temperature may be changed as necessary in consideration of other processes and other factors.

Here, the first monolayer, the second monolayer, and the multilayer thereof may be any one or more of a data line, a scan line, a gate electrode, and a source / drain electrode of a flat panel display device.

Hereinafter, the present invention will be described in detail through examples. However, the following examples and the like are provided to explain the present invention in more detail, and the scope of the present invention is not limited thereto.

Example  One To 12  And Comparative Example 1 to  3 Manufacture: Etchant  Preparation of composition

The etchant compositions were prepared according to the ingredients and composition ratios shown in Table 1 below.

nitric acid
(HNO ₃ )
(weight%) Sulfuric acid
(H ₂ SO ₄₎
(weight%) Oxone
(weight%) Fluorine compound
(weight%) Heterocyclic amine compounds
(weight%) water
(weight%) Example 1 0.5 × 10 NH ₄ HF ₂ 0.1 1,2,3-C ₆ H ₅ N ₃ 0.5 88.9 Example 2 One × 5 NH ₄ HF ₂ 0.3 1,2,3-C ₆ H ₅ N ₃ 0.5 93.2 Example 3 5 × 5 NH ₄ HF ₂ 0.2 1,2,3-C ₆ H ₅ N ₃ 0.7 89.1 Example 4 7 × 3 NH ₄ HF ₂ 0.05 1,2,3-C ₆ H ₅ N ₃ 1.0 88.95 Example 5 × 0.5 10 NH ₄ HF ₂ 0.1 1,2,3-C ₆ H ₅ N ₃ 0.5 88.9 Example 6 × One 5 NH ₄ HF ₂ 0.3 1,2,3-C ₆ H ₅ N ₃ 0.5 93.2 Example 7 × 5 5 NH ₄ HF ₂ 0.2 1,2,3-C ₆ H ₅ N ₃ 0.7 89.1 Example 8 × 7 3 NH ₄ HF ₂ 0.05 1,2,3-C ₆ H ₅ N ₃ 1.0 88.95 Example 9 0.5 0.3 10 NH ₄ HF ₂ 0.1 1,2,3-C ₆ H ₅ N ₃ 0.5 88.6 Example 10 One 0.5 5 NH ₄ HF ₂ 0.3 1,2,3-C ₆ H ₅ N ₃ 0.5 92.7 Example 11 5 One 5 NH ₄ HF ₂ 0.2 1,2,3-C ₆ H ₅ N ₃ 0.7 88.1 Example 12 6 0.5 3 NH ₄ HF ₂ 0.05 1,2,3-C ₆ H ₅ N ₃ 1.0 89.45 Comparative Example 1 0.05 × 0.3 NH ₄ HF ₂ 0.1 1,2,3-C ₆ H ₅ N ₃ 0.7 98.85 Comparative Example 2 3 × 10 NH ₄ HF ₂ 1.5 1,2,3-C ₆ H ₅ N ₃ 0.1 85.4 Comparative Example 3 10 × 25 NH ₄ HF ₂ 0.05 1,2,3-C ₆ H ₅ N ₃ 0.5 64.45

Test Example 1 : Evaluation of etching characteristics

After the Cu and Cu / Mo substrates deposited on the substrate were put into the etching apparatus of experimental equipment (manufactured by SEMES, Inc.), the etching solution compositions of Examples 1 to 12 and Comparative Examples 1 to 3 were heated to 30 ° C. When the temperature reached 30 ± 0.1 ℃, the etching process was performed. The total etching time was performed by giving 40% of over etch based on EPD (End Point Detection). After the substrate was injected and the etching was completed, the substrate was taken out, washed with deionized water, dried using a hot air dryer, and photoresist was removed using a photoresist stripper. After the cleaning and drying, an electron scanning microscope (SEM; manufactured by HITACHI, model name: S-4700) was used to evaluate side loss (side etching) loss, lower layer damage, and etching residue.

Thin film
Kinds Cu Cu / Mo Etch characteristic evaluation result Etch characteristic evaluation result EPD
(sec) S / E
(탆) Underlying membrane damage Residue EPD (sec) S / E (占 퐉) Underlying membrane damage Residue Example 1 45 0.15 × × 52 0.47 × × Example 2 40 0.21 × × 45 0.42 × × Example 3 35 0.24 × × 43 0.45 × × Example 4 32 0.27 × × 39 0.50 × × Example 5 51 0.17 × × 58 0.48 × × Example 6 48 0.23 × × 49 0.44 × × Example 7 40 0.26 × × 46 0.45 × × Example 8 34 0.30 × × 42 0.50 × × Example 9 35 0.10 × × 42 0.44 × × Example 10 32 0.19 × × 39 0.34 × × Example 11 27 0.24 × × 34 0.47 × × Example 12 20 0.30 × × 31 0.50 × × Comparative Example 1 Not etched Not etched Comparative Example 2 10 1.00 ○ × 13 2.30 ○ × Comparative Example 3 Pattern disappearance × × Pattern disappearance × ×

As can be seen in Table 2, when etching using the etchant composition of Examples 1 to 12 according to the present invention, it can be confirmed that good etching characteristics appear. On the other hand, when nitric acid and oxone are less than the content range defined in the present invention, as in Comparative Example 1, copper is not etched, and NH ₄ HF ₂ , which is a fluorine-containing compound, exceeds the content range defined in the present invention, as in Comparative Example 2 If so, there is a loss in the underlying film. In addition, as in Comparative Example 3, when the nitric acid and oxone exceed the content range defined in the present invention, the etching rate is greatly increased, and thus the wiring is lost due to over etching.

FIG. 1A is a SEM photograph of a substrate on which Cu is deposited using the etching composition of Example 2, FIG. 1B is a schematic view of etching the substrate on which Cu is deposited using the etching composition of Example 2, SEM photographs after peeling.

1A and 1B, it can be seen that the pattern shape of copper is excellent and the damage of the lower film does not occur.

FIG. 2A is an SEM photograph of a substrate on which Cu / Mo is deposited using the etchant composition of Example 2, FIG. 2B is a SEM image of the substrate on which Cu / Mo is deposited using the etchant composition of Example 2 , And SEM photographs after peeling off the photoresist.

Referring to FIGS. 2A and 2B, it can be seen that the Cu / Mo does not cause a galvanic phenomenon, so that the profile of the pattern is excellent and the underlying film is not damaged.

3A is a SEM photograph after etching the substrate on which Cu is deposited using the etchant composition of Example 6, and FIG. 3B is a photoresist after etching the substrate on which Cu is deposited using the etchant composition of Example 6. SEM photograph after peeling.

3A and 3B, it can be seen that the pattern shape of copper is excellent and the damage of the lower film does not occur.

4A is a SEM photograph after etching a substrate on which Cu / Mo is deposited using the etchant composition of Example 6, and FIG. 4B is after etching a substrate on which Cu / Mo is deposited using the etchant composition of Example 6. SEM photograph after peeling a photoresist.

Referring to FIGS. 4A and 4B, it can be seen that the Cu / Mo does not cause a galvanic phenomenon, so that the profile of the pattern is excellent and the lower film damage does not occur.

5A is a SEM photograph after etching the substrate on which Cu is deposited using the etchant composition of Example 10, and FIG. 5B is a photoresist after etching the substrate on which Cu is deposited using the etchant composition of Example 10. SEM photograph after peeling.

Referring to FIGS. 5A and 5B, it can be seen that the pattern shape of copper is excellent and the damage of the lower layer does not occur.

6A is a SEM photograph after etching a substrate on which Cu / Mo is deposited using the etchant composition of Example 10, and FIG. 6B is after etching a substrate on which Cu / Mo is deposited using the etchant composition of Example 10. SEM photograph after peeling a photoresist.

6A and 6B, it can be seen that Cu / Mo does not generate a galvanic phenomenon, so the pattern profile is excellent and lower layer damage does not occur.

FIG. 1A is a SEM photograph of a substrate on which Cu is deposited using the etchant composition of Example 2. FIG.

FIG. 1B is an SEM photograph of the substrate after the etching of the substrate on which Cu is deposited using the etching composition of Example 2 and then peeling off the photoresist. FIG.

FIG. 2A is a SEM photograph of a substrate on which Cu / Mo is deposited using the etchant composition of Example 2. FIG.

FIG. 2B is an SEM photograph of a substrate on which Cu / Mo is deposited by using the etching composition of Example 2, and then the photoresist is peeled off.

Figure 3a is a SEM image after etching the substrate on which Cu is deposited using the etchant composition of Example 6.

3B is a SEM photograph after etching a substrate on which Cu is deposited using the etchant composition of Example 6 and then peeling the photoresist.

4A is a SEM photograph after etching a substrate on which Cu / Mo is deposited using the etchant composition of Example 6. FIG.

4B is a SEM photograph after etching a substrate on which Cu / Mo is deposited using the etchant composition of Example 6, and then peeling the photoresist.

Figure 5a is a SEM image after etching the substrate on which Cu is deposited using the etchant composition of Example 10.

FIG. 5B is a SEM photograph after etching a substrate on which Cu is deposited using the etchant composition of Example 10 and then peeling the photoresist.

6A is a SEM photograph after etching a substrate on which Cu / Mo is deposited using the etchant composition of Example 10.

6B is a SEM photograph after etching a substrate on which Cu / Mo is deposited using the etchant composition of Example 10, and then peeling the photoresist.

Claims (9)

For the total weight of the composition, 0.1-7 wt% of one selected from the group consisting of nitric acid, sulfuric acid and mixtures thereof; 0.5 to 20% by weight of Oxone; 0.1 to 1% by weight of a fluorine-containing compound; 0.01-1 weight percent of heterocyclic amine compound; And The remaining amount of water is 100%, An etching liquid composition for etching a first single film comprising copper, a second single film comprising molybdenum or a multiple film comprising the first single film and the second single film. The method according to claim 1, The fluorine-containing compound is an etching solution composition, characterized in that selected from the group consisting of ammonium fluoride, sodium fluoride, potassium fluoride, sodium bifluoride and potassium bifluoride. The method according to claim 1, Wherein said heterocyclic amine compound is selected from the group consisting of imidazole, aminotetrazole, pyrrolidine, pyrroline, pyrrole, indole, pyrazole, pyrimidine, purine and pyridine. The method according to claim 1, Wherein the water is deionized water. The method according to claim 1, The etchant composition further comprises one or more of an etchant, surfactant, metal ion sequestrant, corrosion inhibitor and pH adjusting agent. Forming one or more of a first monolayer comprising copper on the substrate, a second monolayer comprising molybdenum and multilayers thereof; The metal pattern forming method comprising the step of etching any one of the first single layer, the second single layer and the multi-layer using the etchant composition of any one of claims 1 to 5. The method of claim 6, Wherein the first monolayer, the second monolayer, and the multilayer are formed using a vacuum deposition method or a sputtering method. The method of claim 6, The photoresist pattern is formed on any one of the said 1st single film | membrane, the said 2nd single film | membrane, and the said multilayer film. The method of claim 6, Wherein the multiple layers are etched in a batch process.

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