A high-efficiency, low-corrosion chip cleaning solution and its preparation method and application

Abstract

The present invention relates to a high-efficiency, low-corrosion chip cleaning solution, which is calculated by weight and includes the following components: 1-5 parts of a functional agent; 1-5 parts of a chelating agent; 1-10 parts of a cleaning agent; 0.5-2 parts of a surfactant; and 75-95 parts of ultrapure water. The present invention also discloses a preparation method and use of the above-mentioned cleaning solution. The present invention simultaneously uses a functional agent and a cleaning agent, wherein the functional agent guar gum hydroxypropyltrimethylammonium chloride is a high-molecular polysaccharide containing a large number of hydroxyl groups, and metal ions can undergo coupling reactions with ortho-cis hydroxyl groups on different molecular chains in the functional agent, cross-linking different functional agent molecules to form a new spatial network structure, and obtaining a stable system with large branches, so that single metal atoms are also stably anchored in the spatial network structure formed by the functional agent. While cleaning with high efficiency, it has good material compatibility for both metal and non-metallic materials.

Description

Technical Field

[0001] The invention belongs to the field of semiconductor manufacturing technology, and in particular relates to a high-efficiency, low-corrosion chip cleaning solution and a preparation method and application thereof. Background Art

[0002] The size of electronic circuits and components in semiconductor industry microelectronic devices, silicon chips, liquid crystal displays, MEMS (micro-electromechanical systems), printed circuit boards, etc. is decreasing rapidly, and their density is increasing. As the thickness of the insulating layer between each circuit layer continues to decrease and the feature size is getting smaller and smaller, integrated circuits need to be interconnected by layering or stacking. As the feature size decreases, the pattern becomes smaller and smaller, and the device performance parameter requirements become more stringent and robust. Due to the smaller feature size, the reduction in the fault tolerance of the device and the interconnection itself becomes a thorny issue.

[0003] As technology nodes continue to advance, the width of copper wires is getting narrower and narrower. The viscosity of traditional cleaning solvents is relatively high, making it difficult to infiltrate smaller and smaller grooves and voids, and the cleaning effect is greatly reduced. At the same time, more and more materials are being introduced, such as metal materials such as cobalt and tantalum, and low-k dielectric materials such as SiON, BDI / BDII, which in turn poses a challenge to the compatibility of traditional fluorine-containing cleaning solutions with a variety of materials.

[0004] Developing a cleaning solution with good cleaning effect and strong material compatibility has become a problem that needs to be solved urgently in this field.

[0005] Here, we propose a cleaning solution that can achieve fast cleaning and low corrosion, which is used to overcome the problem that traditional cleaning solutions have poor cleaning effects on structures with narrow line widths and high aspect ratios. At the same time, the present invention has good compatibility with metal materials and low-k materials and will not cause excessive corrosion problems. Summary of the invention

[0006] The technical problem solved by the present invention is that the traditional cleaning solution has a poor cleaning effect on structures with narrow line width and high aspect ratio.

[0007] In view of the technical problems existing in the prior art, the present invention provides a high-efficiency, low-corrosion chip cleaning solution and a preparation method and application thereof, wherein the cleaning solution has extremely excellent cleaning efficiency.

[0008] It should be noted that, in the present invention, unless otherwise specified, the specific meaning of "including" in relation to composition limitations and descriptions includes both open-ended "including", "comprising" and similar meanings, and closed-ended "consisting of..." and similar meanings.

[0009] In order to solve the above-mentioned technical problems, the present invention adopts the following solutions:

[0010] A high-efficiency, low-corrosion chip cleaning solution, characterized in that it comprises the following components, calculated by weight:

[0011]

[0012] The functional agent is a water-soluble polysaccharide macromolecular polymer.

[0013] Furthermore, the functional agent is one or more of guar hydroxypropyltrimethylammonium chloride (CAS No.: 65497-29-2), hydroxypropyl guar (CAS No.: 39421-75-5), and carboxymethyl hydroxypropyl guar (CAS No.: 68130-15-4).

[0014] Furthermore, the chelating agent is an organic phosphonic acid substance.

[0015] Furthermore, the chelating agent is one or more of hydroxyethylidene diphosphonic acid, aminotri(methylene phosphonic acid), ethylenediaminetetra(methylene phosphonic acid), and diethylenetriaminepenta(methylene phosphonic acid).

[0016] Furthermore, the cleaning agent is an ascorbic acid derivative.

[0017] Furthermore, the cleaning agent is one or more of L-ascorbic acid 2-phosphate sesquimagnesium salt hydrate, 2-phospho-L-ascorbic acid, 3-O-ethyl-L-ascorbic acid, and ascorbyl glucoside.

[0018] Furthermore, the surfactant is an alkyl glycoside nonionic surfactant.

[0019] Furthermore, the surfactant is one or more of decyl glucoside, dodecyl glucoside, dodecyl-β-D-maltoside, and tetradecyl-β-D-maltoside.

[0020] Furthermore, the cleaning solution is acidic.

[0021] Furthermore, the pH of the cleaning solution is 5-7.

[0022] Furthermore, the pH value of the cleaning solution is 6-7.

[0023] The present invention also discloses a method for preparing a high-efficiency, low-corrosion chip cleaning solution, which is characterized by comprising the following steps:

[0024] Step 1: Weigh each component in its respective amount;

[0025] Step 2: Stir all components at room temperature until a clear and transparent solution is formed to obtain the semiconductor chip cleaning solution.

[0026] The present invention also discloses a method for using a high-efficiency, low-corrosion chip cleaning solution, which is characterized by comprising the following steps:

[0027] Step 1: The semiconductor chip cleaning solution is prepared into an aqueous solution with a mass percentage concentration of 20-100% using ultrapure water, and then the aqueous solution is used to soak and clean the sample at 30-70° C. for 60-180 seconds to obtain a cleaned semiconductor chip;

[0028] Step 2: Rinse the cleaned semiconductor chip in ultrapure water twice and blow dry the surface moisture with nitrogen gas, thus completing the cleaning process of the semiconductor chip.

[0029] The invention also discloses the use of a high-efficiency, low-corrosion chip cleaning solution in cleaning semiconductor chips.

[0030] Furthermore, the cleaning solution can be used to clean residues after Cu process etching.

[0031] In the cleaning liquid system of the present invention, in order to further optimize the effect, each component can be optimized, 2-3 parts of functional agent; 3-4 parts of chelating agent; 5-7 parts of cleaning agent; 1-2 parts of surfactant; 85-90 parts of ultrapure water.

[0032] In the present invention, the functional agent is guar hydroxypropyltrimethylammonium chloride.

[0033] In the present invention, the chelating agent is hydroxyethylidene diphosphonic acid.

[0034] In the present invention, the cleaning agent is L-ascorbic acid 2-phosphate sesquimagnesium salt hydrate.

[0035] In the present invention, the surfactant is decyl glucoside.

[0036] In the present invention, the functional agent has a special role:

[0037] Functional agents have the advantages of fast cleaning and strong material compatibility. They have excellent cleaning performance, can quickly remove post-etching residues, have good compatibility with metal materials and low-k materials, and will not cause excessive corrosion problems. Among them, the functional agent guar gum hydroxypropyl trimethyl ammonium chloride is a high molecular polysaccharide containing a large number of hydroxyl groups. Metal ions can undergo coupling reactions with ortho-cis hydroxyl groups on different molecular chains in the functional agent, cross-link different functional agent molecules to form a new spatial network structure, and obtain a stable system with large branches. Single metal atoms are therefore stably anchored in the spatial network structure formed by the functional agent. The N and O heteroatoms introduced into the guar gum hydroxypropyl trimethyl ammonium chloride structure rely on lone pairs of electrons to form stable coordination bonds with the metal surface, and then form a stable protective film on the metal surface, thereby inhibiting metal corrosion and achieving excellent corrosion inhibition effects.

[0038] In the present invention, the chelating agent has a unique effect:

[0039] Chelating agents are organic phosphonic acid compounds that can form stable complexes with various metal ions such as iron, copper, and zinc, dissolve oxides on the metal surface, and maintain an acidic pH environment.

[0040] In the present invention, the cleaning agent has a unique effect:

[0041] The addition of cleaning agents can quickly precipitate metal ions and prevent pollutants from reattaching, while dispersing and suspending dirt and ash, and can work together with functional agents to clean residues.

[0042] In the present invention, in the method for using the cleaning solution, the temperature of the aqueous solution used in step 1 is 40-60° C., and the cleaning time is 90-150 seconds.

[0043] The present invention provides a high-efficiency, low-corrosion chip cleaning solution and a preparation method and application thereof, which have the following beneficial effects:

[0044] 1. The present invention uses functional agents and cleaning agents in synergy, wherein the functional agent guar gum is a high molecular weight polysaccharide containing a large number of hydroxyl groups. Metal ions can undergo coupling reactions with ortho-cis hydroxyl groups on different molecular chains in the functional agent, cross-linking different functional agent molecules to form a new spatial network structure, thereby obtaining a stable system with large branches. Single metal atoms are therefore stably anchored in the spatial network structure formed by the functional agent, thereby inhibiting metal corrosion and achieving excellent corrosion inhibition effect.

[0045] 2. The cleaning solution of the present invention has good material compatibility with both metal and non-metal materials while cleaning efficiently.

[0046] 3. The cleaning solution of the present invention does not use traditional fluoride, is relatively safe, pollution-free and has low volatile loss. After cleaning, the chip does not need to be rinsed with acetone, but only needs to be rinsed with pure water, which is harmless to the environment and human body.

[0047] 4. The cleaning solution of the present invention has no special requirements for the chip non-corrosive cleaning process, and can completely wash away the residues adhering to the chip without ultrasonic treatment. It only needs to be rinsed with pure water afterwards, and no dirt remains after washing.

[0048] Therefore, the cleaning solution of the present invention has very good application prospects and large-scale industrial promotion potential in the field of semiconductor chip cleaning. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 : A scanning electron microscope (SEM) image of the etched chip before cleaning, magnified 50,000 times.

[0050] Figure 2 : This is a scanning electron microscope (SEM) image of the chip after being cleaned using the cleaning solution prepared in Example 1, magnified 50,000 times.

[0051] Figure 3 : This is a scanning electron microscope (SEM) image of the chip after cleaning with the cleaning solution prepared in Comparative Example 1, magnified 50,000 times. DETAILED DESCRIPTION

[0052] The present invention will be further described below in conjunction with specific embodiments and accompanying drawings:

[0053] Table 1 Examples 1-6

[0054]

[0055]

[0056] Table 2 Comparative Examples 1-3

[0057]

[0058] Table 3 Test data

[0059]

[0060] The preparation method of the high-efficiency, low-corrosion chip cleaning solution of the present invention comprises the following steps:

[0061] Step 1: Weigh each component in its respective amount;

[0062] Step 2: Stir all components at room temperature until a clear and transparent solution is formed to obtain the semiconductor chip cleaning solution.

[0063] The method for using the high-efficiency, low-corrosion chip cleaning solution of the present invention comprises the following steps:

[0064] Step 1: The semiconductor chip cleaning solution is prepared into an aqueous solution with a mass percentage concentration of 100% using ultrapure water, and then the aqueous solution is used to soak and clean the sample at 40° C. for 90 seconds to obtain a cleaned semiconductor chip;

[0065] Step 2: Rinse the cleaned semiconductor chip in ultrapure water twice and blow dry the surface moisture with nitrogen gas, thus completing the cleaning process of the semiconductor chip.

[0066] About performance testing and description:

[0067] The test methods for cleaning effect and corrosion rate are:

[0068] Performance 1 Cleaning effect test method:

[0069] The chip is cleaned using the cleaning solution of the above embodiment and comparative example of the present invention, and the cleaning method comprises the following steps:

[0070] Step 1: soaking and cleaning the semiconductor Cu process chip cleaning solution at 40° C. for 60-180 seconds to obtain a cleaned semiconductor chip;

[0071] Step 2: Rinse the soaked chip in ultrapure water twice, thus completing the chip cleaning process;

[0072] Step 3: Observe the cleaned chip using a scanning electron microscope (SEM).

[0073] The ultrapure water used in step 2 is deionized water having a resistance of at least 18M.

[0074] Performance 2Cu corrosion rate test method:

[0075] Step 1: Cut the Cu sheet into 3*3cm 2 The sample is tested using a four-point probe resistance meter to measure the pre-corrosion value A1, in units of

[0076] Step 2: Soak the Cu sheet in the semiconductor chip cleaning solution of the present invention at 40° C. for 10 minutes;

[0077] Step 3: Rinse the sample processed in step 2 twice in ultrapure water, blow dry with N2, and use a four-point probe resistance meter to test the post-corrosion value A2 in units of

[0078] Step 4: Corrosion rate calculation formula ER = (A1-A2) / t; where ER is in units of / min, t is the sample processing time, unit is min.

[0079] Performance 3TEOS corrosion rate test method:

[0080] Step 1: Cut the TEOS sample into 3*3cm 2 The sample is tested with a non-metallic film thickness meter to measure the pre-corrosion value A1, in units of

[0081] Step 2: Soak the TEOS sheet in the semiconductor chip cleaning solution of the present invention at 40° C. for 10 minutes;

[0082] Step 3: Rinse the sample processed in step 2 in ultrapure water twice, blow dry with N2, and use a non-metallic film thickness meter to test the post-corrosion value A2 in units of

[0083] Step 4: Corrosion rate calculation formula ER = (A1-A2) / t; where ER is in units of / min, t is the sample processing time, unit is min.

[0084] Analysis of the test results:

[0085] It can be seen from the test data in Table 3 that the functional agent in the embodiment plays an important cleaning role, and the cleaning effect decreases as its added amount decreases; in addition, under the same number of functional agents, if the number of cleaning agents decreases, the cleaning effect also decreases; the chelating agent and the functional agent play a corrosion inhibition role at the same time, and the lack of one of them will greatly increase the corrosion rate; and the cleaning effect of the cleaning solution lacking a certain component in Comparative Examples 1 and 2 is significantly reduced; Comparative Example 3 uses hydroxypropyl cellulose as the functional agent, lacks the network structure of the functional agent, and it is difficult to anchor metal ions to form a film, and the corrosion rate is greatly increased compared with Example 1.

[0086] Further comparison is made through the attached drawings in the specification:

[0087] Figure 1 This is a scanning electron microscope (SEM) image of the etched chip before cleaning, magnified 50,000 times. Figure 2 This is a scanning electron microscope (SEM) image of a chip after being cleaned using the cleaning solution prepared in Example 1, magnified 50,000 times. Figure 3 This is a scanning electron microscope (SEM) image of a chip after being cleaned using the cleaning solution prepared in Comparative Example 1, magnified 50,000 times.

[0088] from Figure 1-Figure 3 It can be seen from the comparison that the cleaning solution prepared in Example 1 of the present invention can quickly and thoroughly remove the residues in the chip holes in 90 seconds. In Comparative Example 1, the functional agent is missing and cannot be combined with the residues in the holes in time within 90 seconds. Even if the cleaning time is extended to 180 seconds, the residues in the holes cannot be completely removed, and the cleaning effect is only about 50% of that in Example 1.

[0089] The present invention is described exemplarily above in conjunction with the embodiments and drawings. It is obvious that the implementation of the present invention is not limited to the above-mentioned methods. As long as various improvements are made using the method concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A high-efficiency, low-corrosion chip cleaning solution, characterized in that: Calculated by weight, it includes the following components: The functional agent is a water-soluble polysaccharide macromolecular polymer.

2. The high-efficiency, low-corrosion chip cleaning solution according to claim 1, characterized in that: The functional agent is one or more of guar gum hydroxypropyltrimethylammonium chloride, hydroxypropyl guar gum, and carboxymethyl hydroxypropyl guar gum.

3. The high-efficiency, low-corrosion chip cleaning solution according to claim 1, characterized in that: The chelating agent is an organic phosphonic acid substance.

4. The high-efficiency, low-corrosion chip cleaning solution according to claim 3, characterized in that: The chelating agent is one or more of hydroxyethylidene diphosphonic acid, aminotrimethylene phosphonic acid, ethylenediaminetetramethylene phosphonic acid, and diethylenetriaminepentamethylene phosphonic acid.

5. The high-efficiency, low-corrosion chip cleaning solution according to claim 1, characterized in that: The cleaning agent is an ascorbic acid derivative.

6. The high-efficiency, low-corrosion chip cleaning solution according to claim 5, characterized in that: The cleaning agent is one or more of L-ascorbic acid 2-phosphate sesquimagnesium salt hydrate, 2-phospho-L-ascorbic acid, 3-O-ethyl-L-ascorbic acid, and ascorbic acid glucoside.

7. A method for preparing a high-efficiency, low-corrosion chip cleaning solution according to any one of claims 1 to 6, characterized in that The steps include: Step 1: Weigh the respective amounts of each component; Step 2: Stir all components at room temperature until a clear and transparent solution is formed to obtain the semiconductor chip cleaning solution.

8. A method for using the high-efficiency, low-corrosion chip cleaning solution according to any one of claims 1 to 6, characterized in that The following steps are involved: Step 1: preparing the semiconductor chip cleaning solution with ultrapure water into an aqueous solution with a mass percentage concentration of 20-100%, and then using the aqueous solution to clean the semiconductor chip at 30-70° C. for 60-180 seconds to obtain a cleaned semiconductor chip; Step 2: Rinse the cleaned semiconductor chip in ultrapure water twice and blow dry the surface moisture with nitrogen gas, thus completing the cleaning process of the semiconductor chip.

9. Use of the high-efficiency, low-corrosion chip cleaning solution according to any one of claims 1 to 6 in cleaning semiconductor chips.

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