CN102569036A - Silicon wafer cleaning technology - Google Patents

Silicon wafer cleaning technology Download PDF

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Publication number
CN102569036A
CN102569036A CN201210061167XA CN201210061167A CN102569036A CN 102569036 A CN102569036 A CN 102569036A CN 201210061167X A CN201210061167X A CN 201210061167XA CN 201210061167 A CN201210061167 A CN 201210061167A CN 102569036 A CN102569036 A CN 102569036A
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step
cleaning
silicon chip
put
deionized water
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CN201210061167XA
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Chinese (zh)
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CN102569036B (en
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唐国琴
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常州银河半导体有限公司
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Abstract

The invention discloses a silicon wafer cleaning technology, which takes a cut silicon wafer as a processing object, and is sequentially carried out according to the following steps of: step 1, putting the silicon wafer into an ultrasonic cleaner which contains cleaning mixed solution for cleaning; step 2, rinsing; step 3, drying; step 4, putting the silicon wafer into etchant solution to be corroded; step 5, rinsing; step 6, ultrasonically cleaning the silicon wafer; step 7, rinsing; step 8, drying; and step 9, putting the silicon wafer which is dried in the step 8 into an oven to be dried, i.e. the cleaning of the silicon wafer is finished. The silicon wafer cleaning technology disclosed by the invention has the characteristics of reasonable technology, high cleanness of a silicon wafer surface and the like.

Description

The cleaning of silicon chip

Technical field

The present invention relates to a kind of cleaning that is mainly used in the silicon chip of electronic device, the cleaning of this silicon chip also is applicable to the cleaning of solar silicon wafers.

Background technology

At present, the cleaning of said silicon chip is to be process object with the silicon chip after the cutting, and silicon chip is put into the cleaning solution of breathing out rub powder and deionized water preparation, cleans repeatedly more than three times, and through the drier drying, its concrete processing step is then:

The first step: silicon chip being put into first supersonic wave cleaning machine of breathing out the powder mixed solution that rubs is housed cleans, is 80-85 ℃ in the deionized water temperature, ultrasonic waves for cleaning 15 ~ 20 minutes;

Second step: in first supersonic wave cleaning machine, take out silicon chip, put into the tank flushing that deionized water is housed and take out the back more than eight times;

The 3rd step, silicon chip put into second supersonic wave cleaning machine of breathing out the powder mixed solution that rubs is housed cleans, be 80-85 ℃ in the deionized water temperature, ultrasonic waves for cleaning 15 ~ 20 minutes;

The 4th step, in second supersonic wave cleaning machine, take out silicon chip, put into the tank flushing that deionized water is housed and take out the back more than eight times;

The 5th step, silicon chip is put into the 3rd supersonic wave cleaning machine that deionized water is housed clean, be 80-85 ℃ in the deionized water temperature, ultrasonic waves for cleaning 15 ~ 20 minutes;

The 6th step, in the 3rd supersonic wave cleaning machine, take out silicon chip, put into the tank flushing that deionized water is housed and take out the back more than eight times;

The 7th step, the silicon chip after the flushing of the 6th step to be put into drier dry, i.e. cleaning finishes.

And there is certain shortcoming in the silicon chip existing three rinse mode of washing of giving a baby a bath on the third day after its birth: the first, because to breathe out the powder that rubs be the powdered granule thing; When itself and deionized water preparation cleaning solution, can lump or bond, also can be bonded on the chamber wall even be placed on container for stirring; Water-soluble validity is poor; Therefore, the silicon chip surface after the cleaning is not bright and clean, and cleaning performance is not good; The second, because the silicon chip surface cleanliness factor after cleaning is low, make silicon chip surface understand phenomenons such as spottiness and cut; After the filter paper wiping, filter paper also has the situation of blackout, and silicon chip surface fineness is low, so that silicon chip also will grind and polishing; The electrical property anti-phase that detects silicon chip is general only about 1400NS recovery time; Puncture voltage is also more discrete, and generally in 800 ~ 1400V scope, not only processing technology is loaded down with trivial details, inefficiency to make silicon chip; And the electrical property that detects silicon chip is low, and promptly qualification rate is low; The 3rd owing to will discharge every day in a large number by Kazakhstan rub powder and the formulated cleaning solution of water, therefore, pollute big, energy-conserving and environment-protective inadequately.

Summary of the invention

The objective of the invention is: provide a kind of technology reasonable, the silicon chip cleaning that the silicon chip surface cleannes are high is to overcome the deficiency of prior art.

The technical scheme that realizes the object of the invention is: a kind of cleaning of silicon chip be processing object with the silicon chip through cutting process, and its cleaning is carried out successively according to the following steps:

The first step: silicon chip is put into the supersonic wave cleaning machine that the cleaning mixed solution is housed clean; And scavenging period is controlled in 16 ~ 25 minutes scopes; The FREQUENCY CONTROL of said supersonic wave cleaning machine is in 40 ~ 55Hz scope, and said cleaning mixed solution is by deionized water: cleaning agent is 22 ~ 25: 0.6 ~ 1.0 liquid mixture prepared by volumetric ratio;

Second step: silicon chip that will be after the first step is cleaned, put into the tank that deionized water is housed and repeatedly wash taking-up afterwards;

The 3rd step: will put into drier through the silicon chip after the flushing of second step and dry, and the rotating speed of drier is controlled in 650 ~ 750 rev/mins of scopes;

The 4th step: will put into etchant solution through the silicon chip after the 3rd step dried and corrode, and the time is controlled in 30 ~ 45 seconds scopes; Said etchant solution is by nitric acid: hydrofluoric acid: glacial acetic acid: deionized water is 1 ~ 2:2 ~ 4:1 ~ 2:3 ~ 6.8 liquid mixture prepared by volumetric ratio;

The 5th step: will put into the tank that deionized water is housed through the silicon chip after the corrosion of the 4th step and repeatedly wash the back taking-up;

The 6th step: will put into through the silicon chip after the 5th step flushing and the supersonic wave cleaning machine that cleans mixed solution is housed cleans, and scavenging period is controlled in 16 ~ 25 minutes scopes, the FREQUENCY CONTROL of said supersonic wave cleaning machine is in 40 ~ 55Hz scope; Said cleaning mixed solution is by deionized water: cleaning agent is 22 ~ 25: 0.6 ~ 1.0 liquid mixture prepared by volumetric ratio;

The 7th step: will put into the tank that deionized water is housed through the silicon chip after the 6th step ultrasonic waves for cleaning and repeatedly wash the back taking-up;

The 8th step: will put into drier through the silicon chip after the flushing of the 7th step and dry, and the rotating speed of drier is controlled in 650 ~ 750 rev/mins of scopes;

The 9th step: will put into the baking oven drying 25 ~ 65 minutes through the silicon chip after the 8th step dried, and temperature is controlled in 40 ~ 90 ℃ of scopes, promptly silicon chip cleans and finishes.

In the cleaning of above-mentioned silicon chip, the cleaning agent in the said cleaning mixed solution is that its composition comprises potassium hydroxide, anion/cation surfactant, the JH-16 cleaning agent of complexing agent and antifoaming agent.

In the cleaning of above-mentioned silicon chip, before the silicon chip after the 3rd step dried flushing, also comprise cleaning, water-washing step once more; Saidly clean once more, water-washing step, be silicon chip to be put into once more the supersonic wave cleaning machine that cleans mixed solution is housed cleans, and scavenging period is controlled in 10 ~ 20 minutes scopes; After the silicon chip ultrasonic waves for cleaning, put into the tank that deionized water is housed again and repeatedly wash the back taking-up, and then get into the 3rd step drying step.That is to say that said cleaning, the visual actual conditions of water-washing step need repeatedly to carry out repeatedly.

The present invention advocates to clean for 2 ~ 3 times, water-washing step hockets repeatedly; And described washed with de-ionized water number of times, in 3 ~ 10 underranges.

Technique effect of the present invention is: used cleaning solution is formulated by cleaning agent and deionized water in the cleaning of the present invention; Because cleaning agent is a liquid; When itself and deionized water preparation cleaning solution; Water-soluble validity is high, the not only surperficial immaculate of the silicon chip after the cleaning, anhydrous mark and no marking, and clean thorough; Adopt filter paper in silicon chip surface wiping check back and forth, the filter paper surface does not have blackout and changes, and therefore, the silicon chip surface cleannes after the cleaning are high, and cleaning performance is good; Again because the cleaning performance of silicon chip is good; And silicon chip is through corrosion treatment; Make silicon chip surface have 3 microns attenuate effect, can improve the fineness of silicon chip surface, and need not to grind and polishing; Detect the electrical property anti-phase of silicon chip and can bring up to about 1800NS recovery time, the breakdown potential pressure energy focuses in 1280 ~ 1500V scope.Not only the silicon chip cleaning is simple in the present invention, high efficiency, and electrical property is high, and qualification rate is high; The cleaning solution that the present invention uses can be reused more than 20 times, and the reduction that the used etchant solution of silicon slice corrosion only need add behind acid and the pasc reaction gets final product, and therefore, can significantly reduce the discharge capacity of solution, and energy-conserving and environment-protective.

Embodiment

Description below in conjunction with embodiment is further described the present invention, but is not limited to this.

Embodiment is unless otherwise indicated raw materials used, is the conventional raw material that uses of semicon industry and is commercially available article.

A kind of cleaning of silicon chip be processing object with the silicon chip through cutting process, and this cleaning is carried out successively according to the following steps:

The first step: silicon chip put into the supersonic wave cleaning machine that cleans mixed solution is housed cleans, and scavenging period is controlled in 16 ~ 25 minutes scopes, the FREQUENCY CONTROL of said supersonic wave cleaning machine is in 40 ~ 55Hz scope; Said cleaning mixed solution is by deionized water: cleaning agent is 22 ~ 25: 0.6 ~ 1.0 liquid mixture prepared by volumetric ratio; Its manner of formulation is to be under 40 ~ 60 ℃ in the deionized water temperature, and deionized water and cleaning agent were mixed and stir 5 ~ 10 minutes, promptly gets and cleans mixed solution.Wherein, then a little less than the active ability of cleaning agent, may cause the cleaning performance of silicon chip bad if the temperature of deionized water is lower than 40 ℃; If the temperature of deionized water is higher than 60 ℃, then cleaning agent can be because the too high inefficacy of temperature; If the frequency of supersonic wave cleaning machine is lower than 40Hz, then the effect of ultrasonic cleaning is bad, makes that the silicon chip surface cleanliness factor is low; If the frequency of supersonic wave cleaning machine is higher than 55Hz, then the ultrasonic waves for cleaning frequency is too big, causes silicon chip can cause the phenomenon of fragment, influences the rate of finished products of silicon chip;

Second step: silicon chip that will be after the first step is cleaned, put into tank flushing taking-up afterwards more than six times that deionized water is housed;

The 3rd step: will put into drier through the silicon chip after the flushing of second step and dry, and the rotating speed of drier is controlled in 650 ~ 750 rev/mins of scopes;

The 4th step: will put into etchant solution through the silicon chip after the 3rd step dried and corrode, and the time is controlled in 30 ~ 45 seconds scopes; Said etchant solution is by nitric acid: hydrofluoric acid: glacial acetic acid: deionized water is 1 ~ 2:2 ~ 4:1 ~ 2:3 ~ 6.8 liquid mixture prepared by volumetric ratio; Its manner of formulation is earlier deionized water to be poured in the container, then nitric acid, hydrofluoric acid and glacial acetic acid is poured into to mix in the container and stirs 2 ~ 4 minutes, in container, injects deionized water again and mixes and stir 0.5 ~ 1.5 minute, promptly gets etchant solution;

The 5th step: will put into the tank flushing that deionized water is housed through the silicon chip after the corrosion of the 4th step and take out the back more than three times;

The 6th step: will put into the supersonic wave cleaning machine that the cleaning mixed solution is housed through the silicon chip after the flushing of the 5th step and clean; And scavenging period is controlled in 16 ~ 25 minutes scopes; The FREQUENCY CONTROL of said supersonic wave cleaning machine is in 40 ~ 55Hz scope, and said cleaning mixed solution is by deionized water: cleaning agent is 22 ~ 25: 0.6 ~ 1.0 liquid mixture prepared by volumetric ratio.Its manner of formulation is to be under 40 ~ 60 ℃ of conditions in the deionized water temperature, and deionized water and cleaning agent were mixed and stir 5 ~ 10 minutes, promptly gets and cleans mixed solution;

The 7th step: will put into the tank flushing that deionized water is housed through the silicon chip after the 6th step ultrasonic waves for cleaning and take out the back more than six times;

The 8th step: will put into drier through the silicon chip after the flushing of the 7th step and dry, and the rotating speed of drier is controlled in 650 ~ 750 rev/mins of scopes;

The 9th step: will put into the baking oven drying 25 ~ 65 minutes through the silicon chip after the 8th step dried, and temperature is controlled in 40 ~ 90 ℃ of scopes, promptly silicon chip cleans and finishes.

Cleaning agent in the cleaning mixed solution according to the invention is to close Dacroment Co., Ltd by monarch to produce, and the trade mark is JH-16, and its composition comprises potassium hydroxide, anion/cation surfactant, complexing agent and antifoaming agent; Wherein, during as if the employing anion surfactant, after it dissociates, generate the hydrophobicity anion in water, be the electronegative surfactant of part with surface activity effect; If adopt cationic surfactant, after its water-soluble dissociating, the formed hydrophilic group that links to each other with lipophilic group is the surfactant of band positive electricity; The emulsification of anion/cation surfactant, good dispersion; Complexing agent is also referred to as chelating agent, can form the complex ion compound with metal ion; Antifoaming agent is called anti-foaming agent again, can eliminate foam.

Glacial acetic acid in the etchant solution of the present invention is to be produced by Jiangyin chemical reagent factory, and its specification is that top grade is pure, its molecular formula: CH3C00H; Nitric acid is to be produced by Jiangyin chemical reagent factory, and its specification is pure for analyzing, its molecular formula: HNO3; Hydrofluoric acid is to be produced by Jiangyin chemical reagent factory, and its specification is pure for analyzing, its molecular formula: HF.

In order to improve the cleaning performance of silicon chip, make that the cleannes of silicon chip surface are high, before the silicon chip after the 3rd step dried flushing, also comprise cleaning, water-washing step once more; Saidly clean once more, water-washing step, be silicon chip to be put into once more the supersonic wave cleaning machine that cleans mixed solution is housed cleans, and scavenging period is controlled in 10 ~ 20 minutes scopes; After the silicon chip ultrasonic waves for cleaning, put into the tank that deionized water is housed again and repeatedly wash the back taking-up, and then get into the 3rd step drying step.

Lab scale effect of the present invention shows; Adopt the present invention better than the cleaning quality of prior art cleaning; The not only surperficial immaculate of silicon chip after the cleaning, anhydrous mark and no marking; And clean thoroughly, effectively improved the cleannes of silicon chip surface, for making high-quality electronic device silicon chip technical support is provided.

Claims (3)

1. the cleaning of a silicon chip is a processing object with the silicon chip through cutting process, and it is characterized in that: this cleaning is carried out successively according to the following steps:
The first step: silicon chip is put into the supersonic wave cleaning machine that the cleaning mixed solution is housed clean; And scavenging period is controlled in 16 ~ 25 minutes scopes; The FREQUENCY CONTROL of said supersonic wave cleaning machine is in 40 ~ 55Hz scope, and said cleaning mixed solution is by deionized water: cleaning agent is 22 ~ 25: 0.6 ~ 1.0 liquid mixture prepared by volumetric ratio;
Second step: silicon chip that will be after the first step is cleaned, put into the tank that deionized water is housed and repeatedly wash taking-up afterwards;
The 3rd step: will put into drier through the silicon chip after the flushing of second step and dry, and the rotating speed of drier is controlled in 650 ~ 750 rev/mins of scopes;
The 4th step: will put into etchant solution through the silicon chip after the 3rd step dried and corrode, and the time is controlled in 30 ~ 45 seconds scopes; Said etchant solution is by nitric acid: hydrofluoric acid: glacial acetic acid: deionized water is 1 ~ 2:2 ~ 4:1 ~ 2:3 ~ 6.8 liquid mixture prepared by volumetric ratio;
The 5th step: will put into the tank that deionized water is housed through the silicon chip after the corrosion of the 4th step and repeatedly wash the back taking-up;
The 6th step: will put into through the silicon chip after the 5th step flushing and the supersonic wave cleaning machine that cleans mixed solution is housed cleans, and scavenging period is controlled in 16 ~ 25 minutes scopes, the FREQUENCY CONTROL of said supersonic wave cleaning machine is in 40 ~ 55Hz scope; Said cleaning mixed solution is by deionized water: cleaning agent is 22 ~ 25: 0.6 ~ 1.0 liquid mixture prepared by volumetric ratio;
The 7th step: will put into the tank that deionized water is housed through the silicon chip after the 6th step ultrasonic waves for cleaning and repeatedly wash the back taking-up;
The 8th step: will put into drier through the silicon chip after the flushing of the 7th step and dry, and the rotating speed of drier is controlled in 650 ~ 750 rev/mins of scopes;
The 9th step: will put into the baking oven drying 25 ~ 65 minutes through the silicon chip after the 8th step dried, and temperature is controlled in 40 ~ 90 ℃ of scopes, promptly silicon chip cleans and finishes.
2. the cleaning of silicon chip according to claim 1, it is characterized in that: the cleaning agent in the said cleaning mixed solution is that its composition comprises potassium hydroxide, anion/cation surfactant, the JH-16 cleaning agent of complexing agent and antifoaming agent.
3. the cleaning of silicon chip according to claim 1 is characterized in that: before the silicon chip after the 3rd step dried flushing, also comprise cleaning, water-washing step once more; Saidly clean once more, water-washing step, be silicon chip to be put into once more the supersonic wave cleaning machine that cleans mixed solution is housed cleans, and scavenging period is controlled in 10 ~ 20 minutes scopes; After the silicon chip ultrasonic waves for cleaning, put into the tank that deionized water is housed again and repeatedly wash the back taking-up, and then get into the 3rd step drying step.
CN201210061167.XA 2012-03-09 2012-03-09 Silicon wafer cleaning technology CN102569036B (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104051254A (en) * 2014-06-12 2014-09-17 江阴新顺微电子有限公司 Semiconductor chip back side silicon corrosion technique
CN104925742A (en) * 2014-03-20 2015-09-23 中芯国际集成电路制造(上海)有限公司 Forming method of MEMS semiconductor device
CN104986769A (en) * 2014-12-17 2015-10-21 马鞍山明鑫光能科技有限公司 Raw material recovery and cleaning method of IC photolithography sheets

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3338926B2 (en) * 1998-01-16 2002-10-28 東京エレクトロン株式会社 Ultrasonic cleaning equipment
CN102021658A (en) * 2010-12-10 2011-04-20 天津中环领先材料技术有限公司 Heavily doped monocrystalline silicon wafer corrosion technique by alkali corrosion before acid corrosion
CN102021657A (en) * 2010-12-10 2011-04-20 天津中环领先材料技术有限公司 Corrosion process for heavily doped monocrystalline silicon wafers sequentially subjected to acid corrosion and alkaline corrosion

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3338926B2 (en) * 1998-01-16 2002-10-28 東京エレクトロン株式会社 Ultrasonic cleaning equipment
CN102021658A (en) * 2010-12-10 2011-04-20 天津中环领先材料技术有限公司 Heavily doped monocrystalline silicon wafer corrosion technique by alkali corrosion before acid corrosion
CN102021657A (en) * 2010-12-10 2011-04-20 天津中环领先材料技术有限公司 Corrosion process for heavily doped monocrystalline silicon wafers sequentially subjected to acid corrosion and alkaline corrosion

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104925742A (en) * 2014-03-20 2015-09-23 中芯国际集成电路制造(上海)有限公司 Forming method of MEMS semiconductor device
CN104925742B (en) * 2014-03-20 2016-09-07 中芯国际集成电路制造(上海)有限公司 The forming method of MEMS semiconductor devices
CN104051254A (en) * 2014-06-12 2014-09-17 江阴新顺微电子有限公司 Semiconductor chip back side silicon corrosion technique
CN104986769A (en) * 2014-12-17 2015-10-21 马鞍山明鑫光能科技有限公司 Raw material recovery and cleaning method of IC photolithography sheets

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Effective date of registration: 20140212

Address after: 213022 Jiangsu city of Changzhou province Hehai West New District No. 168

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