CN116606704B

CN116606704B - A metal ion cleaning agent for semiconductor materials

Info

Publication number: CN116606704B
Application number: CN202310548240.4A
Authority: CN
Inventors: 何桥; 黄开贵; 李红学
Original assignee: Anhui Yingyou Photoelectric Technology Co ltd
Current assignee: Anhui Yingyou Photoelectric Technology Co ltd
Priority date: 2023-05-16
Filing date: 2023-05-16
Publication date: 2025-04-25
Anticipated expiration: 2043-05-16
Also published as: CN116606704A

Abstract

The invention relates to the technical field of semiconductor cleaning, which comprises the following components in parts by weight: 10% -16% of a surfactant; triethanolamine 0.1% -0.2%; sodium benzoate 2% -5%; phosphate 4% -8%; 3% -6% of sodium silicate; sodium hydroxide 0.5% -1%; oleic acid 0.3% -0.5%; oleyl alcohol 0.5% -0.8%; ethanol 0.6% -1%; the invention discloses a metal ion cleaning agent for semiconductor materials, which forms a mixed homogeneous system, so that the cleaning agent has strong decontamination and degreasing capabilities, and the surface of the cleaned part is smooth, the permeability cavity is good, the wettability is short, the process period is short, the chemical reagent amount is small, the cleaning agent concentration is low, the cleaning agent is easy to wash clean, and the environmental protection performance is high through the synergistic effect and the complementary effect of various substances in the cleaning agent.

Description

Metal ion cleaning agent for semiconductor material

Technical Field

The invention relates to the technical field of semiconductor cleaning, in particular to a metal ion cleaning agent for semiconductor materials.

Background

Chemical cleaning refers to a process of using various chemical reagents and organic solvents to perform chemical reaction or dissolution with impurities and greasy dirt adsorbed on the surface of an object to be cleaned, or using physical measures such as ultrasound, heating, vacuumizing and the like to enable the impurities to be desorbed (desorbed) from the surface of the object to be cleaned, and then flushing the object with a large amount of high-purity hot and cold deionized water so as to obtain a clean surface.

The RCA cleaning process is known as an industry standard wet cleaning process. In production, the RCA method and the improvement based on the RCA cleaning method are commonly used in cleaning the surface of semiconductor materials, wherein the RCA cleaning method mainly comprises a series of chemical liquids which are sequentially invaded into different types, namely a cleaning agent I (APM) and a cleaning agent II (HPM). The preparation of the No. I cleaning Agent (APM) is that deionized water, 30% hydrogen peroxide and 25% ammonia water are used according to the volume ratio of 5:1:1 to 5:2:1, and the preparation of the No. II cleaning agent (HPM) is that deionized water, 30% hydrogen peroxide and 25% hydrochloric acid are used according to the volume ratio of 6:1:1 to 8:2:1. The cleaning principle is that ammonia molecules, chloride ions and the like form stable complexes with heavy metal ions such as copper ions, iron ions and the like, such as [ AuCl4] ^-、[Cu(NH3)4]²⁺、[SiF6]^2-.

When in cleaning, the cleaning is generally carried out at 75-85 ℃ for about 15 minutes, and then the cleaning is carried out by deionized water. Because a large amount of chemical liquid is used for RCA cleaning, the method has great hidden danger to human health and safety, and the factory cost and the pollution to the environment are great because of the use of a large amount of chemical liquid. And the development direction of the cleaning technology in the future is towards the reduction of chemical liquid and cleaning flow.

Therefore, a cleaning process method and related cleaning agent which have the advantages of less cleaning steps, small amount of chemical reagents, low concentration of cleaning liquid and environmental friendliness are needed.

Disclosure of Invention

The invention aims to provide a metal ion cleaning agent for semiconductor materials, which solves the problems of large usage amount, high concentration and environmental pollution of the existing cleaning agent in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme that the metal ion cleaning agent for the semiconductor material comprises the following components in percentage by weight:

10 to 16 percent of surfactant, 0.1 to 0.2 percent of triethanolamine, 2 to 5 percent of sodium benzoate, 4 to 8 percent of phosphate, 3 to 6 percent of sodium silicate, 0.5 to 1 percent of sodium hydroxide, 0.3 to 0.5 percent of oleic acid, 0.5 to 0.8 percent of oleyl alcohol, 0.6 to 1 percent of ethanol and the balance of water.

As a further illustration of the invention, the composition comprises the following components in weight percent:

10% of surfactant, 0.1% of triethanolamine, 2% of sodium benzoate, 4% of phosphate, 3% of sodium silicate, 0.5% of sodium hydroxide, 0.3% of oleic acid, 0.5% of oleyl alcohol, 0.6% of ethanol and the balance of water.

16% of surfactant, 0.2% of triethanolamine, 5% of sodium benzoate, 8% of phosphate, 6% of sodium silicate, 1% of sodium hydroxide, 0.5% of oleic acid, 0.8% of oleyl alcohol, 1% of ethanol and the balance of water.

As a further illustration of the present invention, the surfactants include sodium alkylbenzenesulfonate, polyoxyethylene fatty alcohol ether, polyoxyethylene octyl phenol ether, dodecyl diethanolamide, triethanolamine oleate soap, and dodecyl phosphate diethanolamide salt.

As a further illustration of the invention, the phosphate salts include sodium pyrophosphate, sodium tripolyphosphate, sodium hexametaphosphate, and trisodium phosphate.

As a further illustration of the present invention, the weight ratio of sodium alkylbenzenesulfonate, polyoxyethylene fatty alcohol ether, polyoxyethylene octylphenol ether, dodecyl diethanolamide, triethanolamine oleic soap, and dodecyl phosphate diethanolamide salt is 1:2:2:2:1:1.

As a further illustration of the present invention, the weight ratio of sodium pyrophosphate, sodium tripolyphosphate, sodium hexametaphosphate, and trisodium phosphate is 1:3:1:1.

The application method of the metal ion cleaning agent comprises the steps of soaking and vibrating and cleaning a semiconductor material with the cleaning agent for 10-15 minutes, and then flushing the semiconductor material with deionized water, wherein the soaking and cleaning temperature is controlled to be 10-60 ℃, and the soaking and vibrating and cleaning equipment is megasonic cleaning equipment.

The semiconductor material is a silicon material or a ceramic material.

Use of a metal ion cleaning agent for semiconductor materials in cleaning semiconductor materials.

Compared with the prior art, the invention has the beneficial effects that:

The invention realizes that the metal ion cleaning agent of the semiconductor material forms a mixed homogeneous system through the arranged surfactant, phosphate and deionized water, so that the cleaning agent has strong decontamination and degreasing capabilities, the surface of the cleaned part is smooth, the permeability cavity is good, the parts with complex geometric shapes can be cleaned, the residual cleaning agent is easy to wash away, the toxicity is low, all components in the cleaning agent can be degraded in organisms, no accumulated toxicity is caused, only a small amount of volatile matters of ethanol are less, the gas inhalation hazard does not occur, a small amount of auxiliary agents belong to low toxicity and micro toxicity, no acute and malignant poisoning occur, the cleaning agent is convenient to use, the material can be cleaned by direct soaking vibration cleaning, the cleaning with complex geometric shapes can be cleaned cleanly for 15-20 minutes, the whole process period is short, the chemical reagent amount is low, the cleaning agent is easy to wash cleanly, and the environmental protection performance is high.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments.

The first embodiment of the invention provides a technical scheme that a metal ion cleaning agent for semiconductor materials comprises the following components in percentage by weight:

The invention relates to a cleaning agent mainly comprising a surfactant, and the cleaning function of the cleaning agent is mainly related to the chemical properties of the surfactant. The molecular structure of the surfactant has two parts, namely a hydrophilic group and a lipophilic group. In water, air, oil systems, there is a tendency to accumulate on surfaces or interfaces. The molecules are arranged in an oriented way, hydrophilic groups extend into the water phase, lipophilic groups extend into the air or oil phase, so that the surface or interface tension is reduced, and the effects of permeation, solubilization, emulsification and the like are combined, so that oil stains can be dissolved out of the surface of the part, and the cleaning and washing effects are realized. The balance of auxiliary agents are used for improving and enhancing the chemical activity of the surfactant, buffering the pH value, inhibiting the occurrence of harmful particles, enhancing the function of the cleaning agent and the like.

Specifically, triethanolamine can inhibit hydrolysis of triethanolamine oleic soap, which is itself a surfactant. Sodium benzoate is a good penetrating agent and a solubilizer, and is convenient for mutual dissolution and complementation of various substances in the cleaning agent.

Specifically, sodium silicate, also known as water glass, is a low cost base that generates OH ^-1, to provide alkalinity when hydrolyzed in water. Therefore, sodium carbonate has a buffering action, avoiding corrosion of certain nonferrous metals as strong bases. Stable colloid can be formed in water to form solvated micelle, and the solvated micelle has good washing assisting effect when used together with a surfactant. Silicate can be hydrolyzed in water, silicic acid generated by hydrolysis is insoluble in water, and is suspended in a tank liquor in a micelle structure, and the solvated micelle has suspending and dispersing capacity on particles of solid dirt and has emulsifying effect on the dirt, so that the dirt is prevented from redeposition on the surface of a workpiece. Silicate has a buffering action, i.e. its pH remains almost unchanged in the presence of acidic soils.

Sodium silicate can also form a precipitate with high-valence metal ions in water to generate indissolvable calcium carbonate, so that the sodium silicate has certain softening capacity for hard water. Can remove ferric salt in water, complex calcium and magnesium ions, and has effect of softening water.

Specifically, sodium hydroxide is dissolved in water and ionized to form 0H ^-1 to provide alkalinity, and the sodium hydroxide can be saponified with oil during cleaning to generate glycerin and fatty acid salt which can be dissolved in water and are dissolved and dispersed in aqueous solution. The generated fatty acid sodium soap not only has water solubility, but also plays a role of a surfactant, and can enable inactive greasy dirt to be emulsified and dispersed by residual alkali. The same phenomenon can occur when carboxylic acid groups and sulfonic acid groups are present in the grease. In addition, a small amount of sodium hydroxide can adjust the PH value of the whole cleaning agent, so that the PH value of the cleaning agent is slightly alkaline.

Specifically, oleic acid and sodium salt in the components form sodium oleate which has good detergency and can be used as a surfactant such as an emulsifier.

Specifically, oleyl alcohol and ethanol have low surface tension and small interfacial energy, so when air is mixed into a solution, surfactant molecules are sequentially arranged and adsorbed on a gas-liquid interface, so that formed bubbles have certain viscosity and tend to be stable, a large amount of bubbles are separated by a thin liquid film and are gathered in a large amount to form foam, and a proper amount of foam has the effect of helping to suspend greasy dirt. However, if the foam is too much, the foam can be discharged out of the cleaning machine, so that not only is the field polluted, but also the cleaning agent is lost, and the oleyl alcohol and the ethanol have very effective defoaming effect. When ethanol is used as a solubilizer of oleyl alcohol, liquid adjacent to the surface layer can be taken away when the liquid level of the bubble film spreads, so that the liquid film is locally thinned, and then the liquid film breaks to achieve the purpose of defoaming.

Specifically, the surfactant comprises sodium alkylbenzenesulfonate, polyoxyethylene fatty alcohol ether, polyoxyethylene octyl phenol ether, dodecyl diethanolamide, triethanolamine oleate soap and dodecyl phosphate diethanolamide salt. The weight ratio of the sodium alkylbenzenesulfonate to the polyoxyethylene fatty alcohol ether to the polyoxyethylene octyl phenol ether to the dodecyl diethanolamide to the triethanolamine oleic soap to the dodecyl phosphate diethanolamide salt is 1:2:2:2:1.

The sodium alkyl benzene sulfonate has the functions of decontaminating, wetting, foaming, emulsifying and dispersing, polyoxyethylene fatty alcohol ether, polyoxyethylene octyl phenol ether, dodecyl diethanol amide, triethanolamine oleic soap and dodecyl phosphate diethanol amine salt, which are used for eliminating metal ions adhered to the surface of semiconductor material product.

Specifically, phosphates include sodium pyrophosphate, sodium tripolyphosphate, sodium hexametaphosphate, and trisodium phosphate. The weight ratio of the sodium pyrophosphate to the sodium tripolyphosphate to the sodium hexametaphosphate to the trisodium phosphate is 1:3:1:1.

Trisodium phosphate, when hydrolyzed, generates phosphoric acid with a small degree of dissociation, thereby achieving alkalinity. Therefore, the detergent is a good acid-base buffer agent, so that the PH value of the detergent is stabilized near 9, trisodium phosphate has the effect of softening hard water and obviously promoting the dispersion (emulsification) of dirt particles, and the detergent also has higher alkalinity, so that fat dirt can be dissolved through saponification. Other phosphates, including sodium pyrophosphate, sodium tripolyphosphate, sodium hexametaphosphate, all have an important property in that they are used as multivalent integrator, and the resulting integrator will not precipitate out of the aqueous solution, i.e., the softening of the water by the phosphate will not cause any precipitation. The chelating force for calcium ions is strongest with sodium hexametaphosphate, the chelating force for magnesium ions is strongest with sodium pyrophosphate, and the integrating force of sodium tripolyphosphate for calcium and magnesium ions is between the two. All phosphates, especially sodium tripolyphosphate and sodium dodecyl benzene sulfonate have obvious synergistic effect, and the compound ratio of the two has a cleaning effect which is greatly improved compared with the cleaning effect of single use of one of the phosphates and sodium dodecyl benzene sulfonate. In addition, they have buffering, dispersing and emulsifying action.

In addition, sodium pyrophosphate has certain phosphating effect on metal parts at 50-60 ℃, so that the corrosion resistance of metal materials is improved, and the proper proportion and concentration have no corrosion phenomenon on the product itself, and the roughness of the product is not increased, so that the quality of the product is affected.

The second embodiment is a metal ion cleaning agent for semiconductor materials, which comprises the following components in percentage by weight:

The third embodiment is a metal ion cleaning agent for semiconductor materials, which comprises the following components in percentage by weight:

The use method of the metal ion cleaning agent comprises the steps of soaking and vibrating and cleaning a semiconductor material with the cleaning agent for 10-15 minutes, and then flushing with deionized water, wherein the soaking and cleaning temperature is controlled to be 10-60 ℃, and the soaking and vibrating and cleaning equipment is megasonic cleaning equipment.

The concentration (unit weight percent) of the cleaning solution in the specific method is shown in table 1:

The comparative example is publication No. CN113980747A, which is an alkaline degreasing lotion in cleaning agent for degreasing semiconductor material surface, potassium hydroxide 2.6%, potassium carbonate 2.6%, dipotassium dihydrogen pyrophosphate 3.5%, potassium tripolyphosphate 2.6%, acetonylglycerol 5.5%, sodium dodecyl diphenyl oxide disulfonate 1.4%, H-661.8%, fatty amine polyoxyethylene ether 1.7%, and deionized water in balance

Table 1:

An alkaline degreasing bath was prepared according to the procedure in comparative example. Degreasing test was performed by the test:

Experimental part:

Preparation of Artificial oil stain (weight percent)

Reference is made to JB/T4323.2-1999 Water-based Metal cleaner test methods.

2 Parts of N32HL hydraulic oil (universal machine tool industrial oil);

1 part of industrial white vaseline;

1 part of barium petroleum sulfonate;

Mixing the above components, dissolving at about 120 deg.C, and stirring.

The test piece material adopts 45# steel as a test piece for oil removal rate test. The diameter of the test piece is 50mm, the thickness is 3-5mm, and the surface roughness Ra0.16-0.63.

And (3) clamping absorbent cotton by using tweezers, scrubbing the polished test piece in absolute ethyl alcohol and acetone in sequence, drying by hot air, and cooling in a dryer for later use. The test piece for rust-proof corrosion is not longer than 16 hours after polishing, otherwise, the test piece should be treated again.

Determination of degreasing Rate

Reference is made to JB/T4323.2-1999 Water-based Metal cleaner test methods.

The oiled test piece is placed into a cleaning solution (25C) to be soaked for 3min, then is swayed for 30min, is rinsed for 5s by water and is dried.

Placing the mixture into a dryer for constant weight for 20min, weighing W2, wherein the degreasing rate is as follows:

Degreasing rate = (W1-W2)/(W1-W0) ×100%

Wherein W0 is the weight (g) of the unoiled test piece,

W1 is the weight (g) of the test piece after oiling,

W2 is the weight (g) of the clean test piece with the greasy dirt completely removed.

Degreasing rates are shown in table 2:

TABLE 2

	Degreasing Rate (%)
		Comparative example	88.18
Example two	95.53
		Example III	98.03

As can be seen from Table 2.2, the degreasing rate of the comparative example is low, and the degreasing rate is relatively high by using the cleaning agent of the present invention, and the degreasing rate of both examples II and III exceeds 95%. However, since different cleaning agents have different cloud points, the properties exceeding the cloud points change, thereby affecting degreasing performance, and since degreasing cleaning temperature sometimes needs to be heated, the cleaning agent of the invention performs best when used at a temperature of 20-50 ℃.

In addition, when the cleaning agent removes metal ions, the amount of phosphate chelated metal ions is shown in table 3:

TABLE 3 Table 3

The degreasing rate of the surfactant is reduced due to calcium and magnesium ions in water, and the phosphate can be added to play roles in dispersing, coordinating and preventing oil stains from depositing, and the pH value of the solution can be regulated to improve the degreasing performance of the surfactant. If sodium carbonate is added, precipitation occurs, so that phosphate such as sodium tripolyphosphate is selected as a pH regulator to improve cleaning dispersion performance.

In the fifth embodiment, the semiconductor material is a silicon material or a ceramic material. Use of a metal ion cleaning agent for semiconductor materials in cleaning semiconductor materials.

All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

Claims

1. A metal ion cleaning agent for semiconductor materials, characterized in that it comprises the following components in weight percentage:

Surfactant 10%-16%; triethanolamine 0.1%-0.2%; sodium benzoate 2%-5%; phosphate 4%-8%; sodium silicate 3%-6%; sodium hydroxide 0.5%-1%; oleic acid 0.3%-0.5%; oleyl alcohol 0.5%-0.8%; ethanol 0.6%-1%; the balance is water;

The surfactant includes: sodium alkylbenzene sulfonate, polyoxyethylene fatty alcohol ether, polyoxyethylene octylphenol ether, dodecyl diethanolamide, triethanolamine oleic acid soap and dodecyl phosphate diethanolamine salt;

The phosphates include sodium pyrophosphate, sodium tripolyphosphate, sodium hexametaphosphate and trisodium phosphate;

The weight ratio of the sodium alkylbenzene sulfonate, polyoxyethylene fatty alcohol ether, polyoxyethylene octylphenol ether, dodecyl diethanolamide, triethanolamine oleic acid soap and dodecyl phosphate diethanolamine salt is: 1:2:2:2:1:1;

The weight ratio of the sodium pyrophosphate, sodium tripolyphosphate, sodium hexametaphosphate and trisodium phosphate is 1:3:1:1.

2. The metal ion cleaning agent for semiconductor materials according to claim 1, characterized in that it comprises the following components in weight percentage:

Surfactant 10%; triethanolamine 0.1%; sodium benzoate 2%; phosphate 4%; sodium silicate 3%; sodium hydroxide 0.5%; oleic acid 0.3%; oleyl alcohol 0.5%; ethanol 0.6%; the balance is water.

3. The metal ion cleaning agent for semiconductor materials according to claim 1, characterized in that it comprises the following components in weight percentage:

Surfactant 16%; triethanolamine 0.2%; sodium benzoate 5%; phosphate 8%; sodium silicate 6%; sodium hydroxide 1%; oleic acid 0.5%; oleyl alcohol 0.8%; ethanol 1%; the balance is water.

4. The metal ion cleaning agent for semiconductor materials according to claim 1, characterized in that the semiconductor material is silicon material or ceramic material.

5. Use of the metal ion cleaning agent for semiconductor materials according to any one of claims 1 to 4 in cleaning semiconductor materials.