CN100490185C - Method for reclaiming and utilizing semiconductor device and IC silicon single crystal waste slices - Google Patents
Method for reclaiming and utilizing semiconductor device and IC silicon single crystal waste slices Download PDFInfo
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- CN100490185C CN100490185C CN 200610049528 CN200610049528A CN100490185C CN 100490185 C CN100490185 C CN 100490185C CN 200610049528 CN200610049528 CN 200610049528 CN 200610049528 A CN200610049528 A CN 200610049528A CN 100490185 C CN100490185 C CN 100490185C
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
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Abstract
The invention discloses the method of reclaiming and utilizing the silicon single crystal waste of semiconductor device and integrated circuit. The method comprises the following steps: removing magnesium, aluminium, manganese, zinc, chromium, iron, nickel, tin and lead from discarded silicon chip with HCl and H2SO4, removing copper, mercury and silver with HNO3, dissolving and reclaiming the gold and platinum with the mixture of dense HCl and dense HNO3, removing metal silicide, silicon oxide and silicon nitride with the mixture of dense HF and dense HNO3, removing the active region of component with single reduction and double-faced lapping reduction method, polishing, washing, classifying, detecting, and getting the silicon single crystal polishing chip. The method effectively utilizes the waste silicon chip and saves the production cost of semiconductor device and integrated circuit.
Description
Technical field
The present invention relates to the recoverying and utilizing method of a kind of semiconductor device and IC silicon single crystal waste slices.
Background technology
In semi-conductor discrete device (abbreviation semiconductor device) and semiconductor integrated circuit industry, be extensive use of silicon single-crystal polishing plate, the active area of semiconductor device and semiconductor integrated circuit all is produced on several microns to tens microns zones of silicon chip front surface, and obvious variation does not take place for the silicon structure of polished silicon slice inside and composition.Produce each operation at semiconductor device and semiconductor integrated circuit, there are the various waste silicon chip that cause component failure to produce because of a variety of causes in the capital, also have the test pieces that each operation uses and accompany sheet,, will cause resource to waste greatly if this part discarded sheet is disposed when the calcellation sheet.
Over nearly 2 years, countries such as the particularly Japanese U.S. of national governments Europe, use financial subsidies, vigorously support the utilization of solar energy, the silicon solar cell development is very rapid, and cause the international market polycrystalline silicon raw material very in short supply, price is doubled, the recovery of silicon materials with utilize meaning again with particular importance.
The present invention has effectively utilized the waste silicon chip of semi-conductor discrete device and semiconductor integrated circuit, through a series of processing, removed the silicon physical layer in the silicon chip certain thickness, simultaneously that this is a part of impurity and structure variation are together removed, again through polishing, cleaning, resulting silicon single-crystal polishing plate can be used for the test pieces of semiconductor device and semiconductor integrated circuit and accompanies sheet, the application of this invention to help the production cost of resource circulation utilization and reduction semiconductor device and semiconductor integrated circuit.
Summary of the invention
The recoverying and utilizing method that the purpose of this invention is to provide a kind of semiconductor device and IC silicon single crystal waste slices.
It is at first with semiconductor device and semiconductor integrated circuit waste silicon chip HCl, H
2SO
4Remove magnesium, aluminium, manganese, zinc, chromium, iron, nickel, tin, metal that lead ratio hydrogen is active, use HNO
3Remove copper, mercury, silver-colored transition metal, with dense HCl and dense HNO
3Mixed-acid dissolution and reclaim gold and platinum, with dense HF and dense HNO
3Mixed acid remove metal silicide, Si oxide, silicon nitride, use earlier thinning single surface then, the method of using the two-sided lapping attenuate again is with the active area in the removal devices technology, obtain the silicon chip of original resistivity, pass through polishing, cleaning, classification, detection, stepping again, produce silicon single-crystal polishing plate.
Described dense HF and dense HNO
3Add CH in the mixed acid
3COOH, H
3PO
4Or CH
3COOH and H
3PO
4Buffer.The concentration of HCl is 10～30%, H
2SO
4Concentration be 10～60%.HNO
3Concentration be 10～70%.Dense HF in the mixed acid: dense HNO
3Proportioning be 1:1～1:10.Dense HCl in the mixed acid: dense HNO
3Proportioning be 3:1～5:1.Thinning single surface adopts single face mechanical reduction machine or single face sand-blasting machine.Wafer lapping machine is adopted in two-sided lapping.Single side polishing machine or Twp-sided polishing machine are adopted in polishing.
The present invention has effectively utilized the waste silicon chip of semi-conductor discrete device and semiconductor integrated circuit, through a series of processing, removed the silicon physical layer in the silicon chip certain thickness, simultaneously that this is a part of impurity and structure variation are together removed, again through polishing, cleaning, resulting silicon single-crystal polishing plate can be used for the test pieces of semiconductor device and semiconductor integrated circuit and accompanies sheet, the application of this invention to help the production cost of resource circulation utilization and reduction semiconductor device and semiconductor integrated circuit.
Embodiment
Technological process of the present invention and technical essential
1. the metal of silicon chip surface, silicide are peeled off
In semiconductor device and integrated circuit technology, because the needs of electrode pin lead-in wire, the silicon chip surface sputter layer of metal of being everlasting film, common metal has aluminium, copper, silver, gold etc., in addition, metal contacts with silicon and forms metal silicide, and silicon and oxygen, nitrogen form Si oxide and silicon nitride, this part metal and compound must at first be removed with chemical method as objectionable impurities.Concrete grammar is as follows:
1) watery hydrochloric acid or dilute sulfuric acid are peeled off light metal
Waste silicon chip is loaded with the special-purpose indigo plant (horse) of spending, and places in watery hydrochloric acid or the dilution heat of sulfuric acid, and metal more active than hydrogen in the metal active sequence list can both react with diluted acid.
As 2Al+3H
2SO
4=Al
2(SO
4)
3+ 3H
2↑
Common metal activity command is as follows
K?Ca?Na?Mg?Al?Zn?Fe?Sn?Pb?(H)?Cu?Hg?Ag?Pt?Au
Reaction is cleaned with deionized water after do not have gas and produce.
Watery hydrochloric acid or dilute sulfuric acid concentration are selected to consider enough fast reaction speed, to consider the convenience and the safety of use simultaneously, because the strong volatility of concentrated hydrochloric acid and the concentrated sulfuric acid is high dehydrated and oxidizability, the watery hydrochloric acid concentration that suggestion is used is 10～30%, and the concentration of dilution heat of sulfuric acid is 10～60%.
2) nitric acid is peeled off transition metal
In the metallized metal activity command, be positioned at hydrogen metal afterwards, can not peel off, at this moment need peel off HNO with nitric acid with watery hydrochloric acid or dilute sulfuric acid
3Concentration be 10～70%.As follows as copper and rare nitric acid and red fuming nitric acid (RFNA) reaction:
3Cu+8HNO
3(rare)=3Cu (NO
3)
2+ 2NO ↑+4H
2O
Cu+4HNO
3(dense)=Cu (NO
3)
2+ 2NO
2↑+2H
2O
Silicon chip is put equally in the Hua Lan (horse) and is reacted with salpeter solution, because metal and nitric acid reaction produce pernicious gas NO, NO
2So,, reaction must be carried out in fume hood, and tail gas discharges after will absorbing pernicious gas with the absorption tower.
3) mixed acid of concentrated hydrochloric acid and red fuming nitric acid (RFNA) (chloroazotic acid) is removed precious metal gold and platinum
Precious metal gold and platinum not with nitric acid reaction, at this moment to use chloroazotic acid, the proportioning of chloroazotic acid be with 36% concentrated hydrochloric acid and 65% red fuming nitric acid (RFNA) by volume 4:1 prepare, reaction equation is:
Au+4HCl+3HNO
3＝HAuCl
4+3NO
2↑+3H
2O
Recyclable Precious Metals-Gold of reacted solution and platinum, concrete processing method is not as content of the present invention.Contain NO in the tail gas
2, discharge after will absorbing pernicious gas with the absorption tower equally.
4) hydrofluoric acid and nitric acid mixed acid stripping metal silicide, Si oxide, nitride.
Removed the silicon chip surface of light metal and heavy metal, metal silicide, Si oxide, nitride etc. may also residually be arranged, these compounds are except with nitration mixture reaction and the dissolving, both do not made and reacted with nitration mixture, because hydrofluoric acid and nitric acid mixed acid and surperficial pasc reaction, along with the dissolving of the silicon substrate that supports these compounds, these compounds also can be peeled off with reaction.
Si+6HF+4HNO
3＝H
2SiF
6+4NO
2↑+4H
2O
Above-mentioned reaction is an exothermic reaction, along with the temperature of carrying out solution of reaction is more and more higher, reaction speed is also more and more faster, too fast reaction speed can cause the inhomogeneities of reacting, it is thick more to make that silicon chip goes at the edge, it is big that thereby the gross thickness that makes silicon chip poor (TTV) becomes, for controls reaction speed can add CH in nitration mixture
3COOH, H
3PO
4Or CH
3COOH and H
3PO
4Buffer.HF:HNO in the nitration mixture
3Proportioning be 1:1～1:10.Reaction goes thick amount to be as the criterion with control, is generally 10um.
The nitrogen oxide that forms in the reaction (NO, NO
2) be toxic and harmful, be reflected in the equipment of ventilation and carry out, tail gas discharges after will absorbing pernicious gas with the absorption tower.
2. single face subtracts the book technology, removes the silicon layer of silicon chip front surface device active region
In semiconductor device and integrated circuit technology, the device area of silicon chip front surface, through diffusion, ion injection, oxidation etc., this layer silicon of silicon chip front surface, very big variation has all taken place in its chemical composition and structure, subtracts the book machine with single face, uses cutting or grinding knife tool, remove the certain thickness silicon layer of front surface, with the removal devices active area.
Thinning single surface machine and single face sand-blasting machine can be realized the thinning single surface of silicon chip, but this method need be used special-purpose machine, and cost is higher, so, when active area not too thick, generally be no more than 20um can directly remove silicon simultaneously with the method for two-sided attenuate tow sides, can save thinning single surface thus.
3. the two-sided book technology that subtracts
The front surface of integrated circuit silicon chip is the active area of device, this part silicon layer must be removed, impurity-absorbing technique outside silicon chip back adopts in integrated circuit processing, make objectionable impurities enrichment overleaf, surface contamination in the course of processing also makes silicon chip back that more impurity is arranged simultaneously, therefore, the silicon layer of the several microns in the silicon chip back side (um) also must be removed.
Double cutting separating disk machine with routine carries out two-sided lapping to silicon chip, can remove the silicon layer of the positive and negative of silicon chip simultaneously.General abrasive disc removes thick 60～80um, and positive and negative can be removed 30～40um simultaneously.The most of machining damage that produces in the operation before abrasive disc can be removed can reduce the roughness of silicon chip surface and make surfacing simultaneously.
4. silicon chip cleans, changes rotten
Silicon chip is residual through the two-sided lapping rear surface grit and a chemical reagent, and the metal impurities that grind on the mill, these impurity have a strong impact on generation to road, back device operation, usually with the cleaning agent of special use and add ultrasonic waves for cleaning, clean with deionized water again, dry silicon chip surface with drier at last.
Need carry out chemical corrosion before the silicon wafer polishing, to remove most of machining damage of abrasive disc, the change corruption has the acidifying corruption and alkalizes rotten two kinds, all is common process, and the silicon chip after the change corruption is difficult to stain, and is easy to preservation.
5. the check of silicon chip, test, classification, stepping
Semiconductor device and semiconductor integrated circuit silicon single crystal waste slices are handled through multistep as above, the silicon structure and the component variation layer of silicon chip surface have been removed, the silicon body that stays is the seldom silicon single crystal flake of structural integrity of impurity, and the silicon chip of handling need reach requirement to confirm recycling through verification test.
To confirm that at first the active area or the graph layer of silicon chip front surface removed totally, method is that two surfaces with the microscopic examination silicon chip have not had semiconductor device and semiconductor integrated circuit figure, measure the resistivity of each point in the silicon chip with the four point probe resistivity tester, the resistivity measurement of each point except have the distinctive radially resistivity of silicon single crystal flake inhomogeneous, can not have because of changing the resistivity contrasts that test point causes.
The minority carrier lifetime of its less important measurement silicon chip or diffusion length reach requirement with the content of confirming the beavy metal impurity in the silicon.
By the silicon chip of above-mentioned measurement, prove that semiconductor device and IC silicon single crystal waste slices through handling the qualitative characteristics that has recovered former monocrystalline silicon piece, can be used for semiconductor device and test of semiconductor integrated circuit sheet and the material piece of accompanying sheet.
Since different producer and different purposes to the test pieces of silicon single-crystal polishing plate with accompany sheet that different requirements is arranged, so, need mainly contain following several to the further testing classification of the silicon single crystal flake of handling well.
1) conduction type, crystal orientation test.。
The integrated circuit waste silicon chip seldom can also be by the assortment of silicon chip and since be not each producer all by standard-required, can not discern the kind of silicon chip by the major-minor plane of reference, so the conduction type of silicon chip and crystal orientation need testing classification again.
The silicon chip of gently mixing is measured conduction type with three probes, and heavily doped silicon chip is measured with the cold-hot probe method, and this is a kind of method of testing commonly used, and it still is the P type that instrument is directly read the N type.
The available X ray orientation of the measurement in crystal orientation is measured, this method can accurately measure the crystal orientation and the crystal orientation of crystal and depart from, another kind of simple method can judge simply silicon crystal be＜111 or＜100, it is to shine silicon chip surface with infrared light, infrared light spot according to reflection is judged, if " Y " font then is＜111 〉, if " ten " font then is＜100 〉.
2) measurement of resistivity and stepping
With four point probe resistivity tester or ADE non-contact type resistivity tester, silicon chip is carried out resistivity measurement and stepping, to satisfy different customer requirements.
3) measurement of thickness and stepping
With amesdial or ADE non-contact type Thickness measuring instrument, silicon chip is carried out thickness measure and stepping, to satisfy different customer requirements.
6. the polishing of silicon chip and cleaning
Carrying out sorted group through the silicon chip after the above-mentioned processing by client's specification requirement criticizes, then by common polishing, cleaning, polish and clean, carry out final inspection by requirement of client again, pack after qualified, make the finished product of polished silicon wafer at last, be used for the test pieces of semiconductor device and semiconductor integrated circuit and accompany sheet.
Claims (5)
1. the recoverying and utilizing method of semiconductor device and IC silicon single crystal waste slices is characterized in that, it at first with semiconductor device and semiconductor integrated circuit waste silicon chip with HCl, H
2SO
4Remove magnesium, aluminium, manganese, zinc, chromium, iron, nickel, tin, metal that lead ratio hydrogen is active, use HNO
3Remove copper, mercury, silver-colored transition metal, with dense HCl and dense HNO
3Mixed-acid dissolution and reclaim gold and platinum, with dense HF and dense HNO
3Mixed acid remove metal silicide, Si oxide, silicon nitride, use earlier thinning single surface then, the method of using the two-sided lapping attenuate again is with the active area in the removal devices technology, obtain the silicon chip of original resistivity, pass through polishing, cleaning, classification, detection, stepping again, produce silicon single-crystal polishing plate, the concentration of described HCl is 10～30%, H
2SO
4Concentration be 10～60%, HNO
3Concentration be 10～70%, dense HCl: dense HNO
3Proportioning be 3: 1～5: 1, dense HF: dense HNO
3Proportioning be 1: 1～1: 10.
2. the recoverying and utilizing method of a kind of semiconductor device according to claim 1 and IC silicon single crystal waste slices is characterized in that described dense HF and dense HNO
3Add CH in the mixed acid
3COOH, H
3PO
4Or CH
3COOH and H
3PO
4Buffer.
3. the recoverying and utilizing method of a kind of semiconductor device according to claim 1 and IC silicon single crystal waste slices is characterized in that described thinning single surface adopts single face mechanical reduction machine or single face sand-blasting machine.
4. the recoverying and utilizing method of a kind of semiconductor device according to claim 1 and IC silicon single crystal waste slices is characterized in that described two-sided lapping employing wafer lapping machine.
5. the recoverying and utilizing method of a kind of semiconductor device according to claim 1 and IC silicon single crystal waste slices is characterized in that described polishing employing single side polishing machine or Twp-sided polishing machine.
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|---|---|---|---|
| CN 200610049528 CN100490185C (en) | 2006-02-17 | 2006-02-17 | Method for reclaiming and utilizing semiconductor device and IC silicon single crystal waste slices |
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|---|---|---|---|
| CN 200610049528 CN100490185C (en) | 2006-02-17 | 2006-02-17 | Method for reclaiming and utilizing semiconductor device and IC silicon single crystal waste slices |
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| CN1806949A CN1806949A (en) | 2006-07-26 |
| CN100490185C true CN100490185C (en) | 2009-05-20 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102856145A (en) * | 2011-06-30 | 2013-01-02 | 东京毅力科创株式会社 | Method for manufacturing silicon part and silicon part for etching treatment device |
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|---|---|---|---|---|
| CN101312111B (en) * | 2007-05-21 | 2010-06-09 | 中芯国际集成电路制造(上海)有限公司 | Wafer cleaning and recovery method |
| CN105185741B (en) * | 2015-07-31 | 2018-08-28 | 深圳市万中和科技有限公司 | A kind of COMS pixel circuits substrate recovery process |
| CN107946179B (en) * | 2017-11-27 | 2020-05-08 | 上海超硅半导体有限公司 | Method for recycling patterned wafer with integrated circuit and polycrystalline layer |
| CN111250863B (en) * | 2020-03-31 | 2021-06-29 | 格物感知（深圳）科技有限公司 | Special aluminum-free welding bonding process |
| CN116190210B (en) * | 2023-04-21 | 2023-07-14 | 江苏芯德半导体科技有限公司 | Reprocessing method of wafer level package |
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2006
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Non-Patent Citations (2)
| Title |
|---|
| 硅片清洗原理与方法综述. 刘传军，赵权，刘春香，杨洪星.半导体情报，第37卷第2期. 2000 |
| 硅片清洗原理与方法综述. 刘传军，赵权，刘春香，杨洪星.半导体情报，第37卷第2期. 2000 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102856145A (en) * | 2011-06-30 | 2013-01-02 | 东京毅力科创株式会社 | Method for manufacturing silicon part and silicon part for etching treatment device |
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