CN1400638A - Method for removing residual polymer after etching process and reducing oxide loss - Google Patents
Method for removing residual polymer after etching process and reducing oxide loss Download PDFInfo
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- CN1400638A CN1400638A CN 01125076 CN01125076A CN1400638A CN 1400638 A CN1400638 A CN 1400638A CN 01125076 CN01125076 CN 01125076 CN 01125076 A CN01125076 A CN 01125076A CN 1400638 A CN1400638 A CN 1400638A
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Abstract
This invention discloses a method of removing polymer protection layer in producing semiconductor elements containing: to form a photoresist layer first to cover an oxide in an internal memory array and to limit the photoresist layer the oxide layer of surrounding circuit zone, then to take the photoresist layer as an etching cover to process a dry etching on the oxide layer and conductive layer of the surrounding circuit zone until exposing base material. After the dry etching, a polymer protection layer is formed on the side wall to maintain etching profile. After removing the photoresist layer, a wet etching is processed with super thin hydrofluoric acid solution or a low temperature mixed acid solution for removing the polymer protection layer and preventing loss of the oxide layer.
Description
Technical field
The removal method of the relevant a kind of polymer of the present invention, particularly relevant a kind of method of removing polymer and reducing oxide loss simultaneously.
Background technology
Along with the density of integrated circuit constantly enlarges, for making chip (chip) area keep the same even dwindling, to continue to reduce the unit cost of circuit, only way is exactly constantly to dwindle circuit design specification (designrule), to meet the high-tech industry developing tendency in future.Along with development of semiconductor, the size of integrated circuit package has tapered to the scope of deep-sub-micrometer.When semiconductor continuously tapers to the scope of deep-sub-micrometer, some problems on microtechnology have been produced.
The progress of integrated circuit has involved the geometric specification downsizing of assembly.In the semiconductor technology of deep-sub-micrometer, for the etched profile of control in the semiconductor dry ecthing procedure must form a polymer protective layer in the etching sidewall in the reacting gas that uses the high-carbon fluorine than (C/F).Yet these polymer must be removed before next processing procedure is carried out, otherwise can cause the problem of successive process.Generally speaking, polymer is removed by the processing procedure of a Wet-type etching.But, when removing polymer, also can cause a large amount of losses of oxide layer to traditional wet etch process.In the manufacture of semiconductor of deep-sub-micrometer, the control of oxidated layer thickness is considerably important, especially design specification (design rule) more hour, formed oxidated layer thickness is thin more, the control of oxidated layer thickness is difficulty more.
In traditional wet etch process, will cause the loss of the sacrificial oxide layer of about 20 to 30 dusts when removing polymer, even the whole etchings of sacrificial oxide layer are removed.If the thickness deficiency of sacrificial oxide layer will produce great influence to follow-up ion implantation manufacture process.On the other hand, for the structure (oxide-nitride-oxide) of the stack layer of the oxide-nitride thing-oxide on peripheral circuit and the internal memory (ONO) for, the thickness of oxide skin(coating) must be controlled very accurately, if the thickness of oxide skin(coating) loses in traditional wet etch process too much, will cause electrical skew, and then reduce the reproducibility of assembly.Therefore, for traditional removal polymer processing procedure, not only processing procedure is complicated and be difficult to the thickness of controlled oxidation thing layer, and this will greatly increase the processing procedure cost.
In view of above-mentioned various reasons, we more need a kind of removal method of new residual polyalcohol, so that promote the productivity ratio and the acceptance rate of successive process.
Summary of the invention
The main purpose of the present invention is to provide a kind of removal method of polymer, reducing the loss of oxide skin(coating) simultaneously, thereby can be applicable in the technology of deep-sub-micrometer of semiconductor subassembly.
Another object of the present invention system provides a kind of removal method of residual polyalcohol, and can reduce the loss of oxide skin(coating) simultaneously, can also reduce sulfuric acid mixture (Sulfuric acid Peroxide Mixture) (SPM) residual particulate, also can keep the thickness of oxide skin(coating) and can not cause the drift of component characteristic.
For achieving the above object, provide a kind of method of removing polymer protective layer according to an aspect of the present invention, be characterized in, comprise the following step at least: provide the semiconductor ground; Form monoxide-nitride-oxide skin(coating) on this semiconductor substrate; Form and limit a photoresist layer on this oxide-nitride-oxide skin(coating); With photoresist layer as an etch mask carry out an anisotropic etching processing procedure with this oxide-nitride of etching-oxide skin(coating) till the surface of exposing this semiconductor substrate to the open air, and this anisotropic etching processing procedure is finished after, form a polymer protective layer on the surface of etching sidewall and this semiconductor substrate with maintenance etching external form; Remove this photoresist layer; And carry out one have a mixed acid solution remove processing procedure to remove this polymer protective layer, wherein, this mixed acid solution is formed by an ammoniacal liquor, a hydrogen peroxide and a deionized water, and its temperature is approximately less than 35 ℃.
For achieving the above object, a kind of method that can avoid oxide loss when removing polymer protective layer is provided according to a further aspect of the invention, be characterized in, at least comprise the following step: the semiconductor ground is provided, has one first conductor layer of a memory array and one second conductor layer of a periphery circuit region on it; Form monoxide-nitride-oxide skin(coating) on described first conductor layer and described second conductor layer; Form a photoresist layer in described oxide-nitride-oxide skin(coating), and limit the described photoresist layer on the described oxide-nitride-oxide skin(coating) that is positioned at described second conductor layer; Described photoresist layer is carried out a dry ecthing procedure with reacting gas of a high-carbon fluorine ratio as an etch mask be positioned at the described oxide-nitride-oxide skin(coating) of described second conductor layer and described second conductor layer till the surface of the described semiconductor substrate that exposes described periphery circuit region to the open air with etching, wherein, after described dry ecthing procedure is finished, on the etching sidewall of described memory array and described periphery circuit region, will form a polymer protective layer to keep etching outline; Remove described photoresist layer; And carry out a wet etch process with a mixed acid solution and a hydrofluoric acid solution to remove described polymer protective layer, wherein, the mixing ratio of described hydrofluoric acid solution is about between 700: 1 to 1500: 1, and the temperature of described mixed acid solution is approximately less than 35 ℃.
As mentioned above; the present invention is by super thin hydrofluoric acid (Ultra Dilute Hydrofluoric acid) solution (UDHF); carry out a wet etch process with high flow capacity and make polymer protective layer be removed fully, and can reduce the loss of oxide skin(coating) simultaneously.Therefore, this method can be applicable in the technology of deep-sub-micrometer of semiconductor subassembly.In addition, this method can be carried out a wet etch process (SC1) by the mixed acid solution (APM) of a low temperature with the removal polymer protective layer, and can reduce the loss of oxide skin(coating) simultaneously.In the present invention, the loss of oxide skin(coating) will be reduced to approximately less than 6 .On the other hand, the present invention can also reduce sulfuric acid mixed solution (SPM) residual particulate, also can keep the thickness of oxide skin(coating) and can not cause the drift of component characteristic.Therefore, the present invention can reduce the complexity and the cost thereof of conventional process.So method of the present invention can meet benefit economically.
Be clearer understanding purpose of the present invention, characteristics and advantage, below in conjunction with accompanying drawing to of the present invention preferable
Embodiment is elaborated.
Description of drawings
Figure 1A to Fig. 1 C is according in first preferred embodiment of the present invention, utilizes the super thin hydrofluoric acid solution of high flow capacity, with the section of structure of the processing procedure of removing polymer protective layer;
Fig. 2 A to Fig. 2 C is according in second preferred embodiment of the present invention, utilizes the mixed acid solution of low temperature, with the section of structure of the processing procedure of removing polymer protective layer; With
Fig. 3 A to Fig. 3 C is according in the 3rd preferred embodiment of the present invention, utilizes the super thin hydrofluoric acid solution of high flow capacity and the mixed acid solution of low temperature, with the section of structure of the processing procedure of removing polymer protective layer.
Embodiment
In order to understand the present invention up hill and dale, detailed step will be proposed in following description.Apparently, execution of the present invention is not defined in the detail that the technical staff had the knack of of semiconductor applications.On the other hand, well-known fabrication steps is not described in the details, with the restriction of avoiding causing the present invention unnecessary.Preferred embodiment of the present invention is described in detail as follows; yet except these are described in detail; the present invention can also have other execution mode, promptly all should be included in the scope of patent protection of the present patent application in equivalence variation and the equivalent replacement done under the prerequisite of spirit of the present invention.
Shown in Figure 1A, in the first embodiment of the present invention, at first provide semiconductor ground 100.Then, form a gate 120 with one first oxide skin(coating) 110 by an optical photomicrography resolution, for example, a polycrystalline silicon gate pole is on semiconductor substrate 100.Then, conformal generation one second oxide skin(coating) 130 is on the surface of gate 120 and semiconductor substrate 100.After, deposition forms a dielectric layer 140, for example, the mononitride layer is on second oxide skin(coating) 130.
Shown in Figure 1B, in the present embodiment, second oxide skin(coating) 130 is carried out an anisotropic etching processing procedure 150 as an etch stop layer, for example, one dry ecthing procedure, till the surface of exposing second oxide skin(coating) 130 to the open air, form a clearance wall 160 simultaneously with etching dielectric layer 140 on the sidewall of gate 120.After wherein above-mentioned anisotropic is scribed journey 150 and is finished, with form a polymer protective layer 170 on the surface of dielectric layer 140 to keep the etching external form.In addition, above-mentioned anisotropic etching processing procedure 150 comprises the reacting gas of a high-carbon fluorine than (C/F) at least, for example, and C
4F
8, CHF
3
Shown in figure 1C, in the present embodiment, carry out one and remove processing procedure 180 to remove polymer protective layer 170.The wherein above-mentioned processing procedure 180 that removes comprises first-class tropism's etch process at least, for example, and a wet etch process.Removes processing procedure 180 and comprise one super thin hydrofluoric acid solution (UDHF) at least, and super thin hydrofluoric acid solution (UDHF) comprises a mixing ratio that is about between 700: 1 to 1500: 1 at least, with its flow approximately greater than 3000 ml/min (cc/min).
Shown in figure 2A, in the second embodiment of the present invention, at first provide semiconductor ground 200.Then, form monoxide-nitride-oxide skin(coating) 210 on semiconductor substrate 200.Then, form and limit a photoresist layer 220 on oxide-nitride-oxide skin(coating) 210.Afterwards; with photoresist layer 220 as an etch mask carry out a dry ecthing procedure 230 with etching oxide-nitride-oxide skin(coating) 210 till the surface of exposing semiconductor substrate 200 to the open air; and after dry ecthing procedure 230 is finished, form a polymer protective layer 240 on the surface of etching sidewall and semiconductor substrate 200 with maintenance etching external form, shown in Fig. 2 B.Wherein above-mentioned dry ecthing procedure 230 comprises the reacting gas of a high-carbon fluorine than (C/F) at least, for example, and C
4F
8, CHF
3
Shown in figure 2C, in the present embodiment, remove photoresist layer 220.Then, carry out one and remove processing procedure 250 to remove polymer protective layer 240, the wherein above-mentioned processing procedure 250 that removes comprises a wet etch process (SC1) at least.Remove the mixed acid solution (APM) that processing procedure 250 comprises a low temperature at least, and mixed acid solution (APM) comprises an ammoniacal liquor (NH at least
4OH), a hydrogen peroxide (H
2O
2) and a deionized water (Deionized water) (DI Water) be about between 1: 1: 5 to 1: 1: 40, and its temperature is approximately less than 35 ℃.
Shown in figure 3A, in the third embodiment of the present invention, at first provide semiconductor ground 300, have the polysilicon layer 330A of a memory array 310 and the polysilicon layer 330B of a periphery circuit region 320 on it.Then, form monoxide-nitride-oxide skin(coating) 340 on polysilicon layer 330A and 330B.Forming a photoresist layer 350 is positioned at the oxide-nitride-oxide skin(coating) 340 of memory array 310 with covering and limits photoresist layer 350 on the oxide-nitride-oxide skin(coating) 340 be positioned at periphery circuit region 320.Then, with photoresist layer 350 as an etch mask carry out a dry ecthing procedure 360 with the oxide-nitride-oxide skin(coating) 340 of etching periphery circuit region 320 and polysilicon layer 330B till the surface of the semiconductor substrate 300 that exposes periphery circuit region 320 to the open air.After dry ecthing procedure 360 is finished, on the etching sidewall of memory array 310 and periphery circuit region 320, will form a polymer protective layer 370 to keep etching outline, shown in Fig. 3 B.Wherein above-mentioned dry ecthing procedure 360 comprises the reacting gas of a high-carbon fluorine than (C/F) at least, for example, and C
4F
8, CHF
3
Shown in figure 3C, in the present embodiment, remove photoresist layer 350.Then, carry out a wet etch process 380 to remove polymer protective layer 370, wherein, wet etch process 380 comprises a mixed acid solution (APM) and super thin hydrofluoric acid solution (UDHF) at least.Super thin hydrofluoric acid solution (UDHF) comprises a mixing ratio that is about between 700: 1 to 1500: 1 at least, and its flow is approximately greater than 3000cc/min.Mixed acid solution (APM) comprises an ammoniacal liquor (NH at least
4OH), a hydrogen peroxide (H
2O
2) and a deionized water (Deionized water)) (DI Water), its blending ratio (NH
4OH: H
2O
2: H
2O) be about between 1: 1: 5 to 1: 1: 40, and its temperature is approximately less than 35 ℃.Like this, can prevent the loss of oxide skin(coating).
Certainly, the present invention can be used on the processing procedure of removing residual polymer, also can be used on any semi-conductive etch process.And in case the loss of oxidation thing, development being used in about removing the processing procedure aspect of residual polymer yet so far by super thin hydrofluoric acid solution and low temperature mixed acid solution (APM) in the present invention.For the processing procedure of deep-sub-micrometer, this method is the processing procedure of a preferable feasible removal residual polymer.
Above-mentioned is preferred embodiment of the present invention only, is not in order to limit the present invention; All other do not break away from the equivalence of being finished under the disclosed spirit to be changed and the equivalence replacement, all should be included in the scope of patent protection of the present patent application.
Claims (10)
1. a method of removing polymer protective layer is characterized in that, comprises the following step at least:
The semiconductor ground is provided;
Form monoxide-nitride-oxide skin(coating) on this semiconductor substrate;
Form and limit a photoresist layer on this oxide-nitride-oxide skin(coating);
With photoresist layer as an etch mask carry out an anisotropic etching processing procedure with this oxide-nitride of etching-oxide skin(coating) till the surface of exposing this semiconductor substrate to the open air, and this anisotropic etching processing procedure is finished after, form a polymer protective layer on the surface of etching sidewall and this semiconductor substrate with maintenance etching external form;
Remove this photoresist layer; And
Carry out one have a mixed acid solution remove processing procedure to remove this polymer protective layer, wherein, this mixed acid solution is formed by an ammoniacal liquor, a hydrogen peroxide and a deionized water, and its temperature is approximately less than 35 ℃.
2. the method that is used for the removal polymer protective layer of semiconductor subassembly manufacturing as claimed in claim 1 is characterized in that described anisotropic etching processing procedure comprises a dry ecthing procedure at least.
3.. the method that is used for the removal polymer protective layer of semiconductor subassembly manufacturing as claimed in claim 1 is characterized in that described anisotropic etching processing procedure comprises one at least and has the reacting gas of high-carbon fluorine than (C/F).
4. the method that is used for the removal polymer protective layer of semiconductor subassembly manufacturing as claimed in claim 1 is characterized in that the described processing procedure that removes comprises a wet etch process at least.
5. the method that is used for the removal polymer protective layer that semiconductor subassembly makes as claimed in claim 1 is characterized in that, the blending ratio of described ammoniacal liquor, a hydrogen peroxide and a deionized water be about 1: 1: 5 to 1: 1: 40 between.
6. the method that can avoid oxide loss when removing polymer protective layer is characterized in that, comprises the following step at least:
The semiconductor ground is provided, has one first conductor layer of a memory array and one second conductor layer of a periphery circuit region on it;
Form monoxide-nitride-oxide skin(coating) on described first conductor layer and described second conductor layer;
Form a photoresist layer in described oxide-nitride-oxide skin(coating), and limit the described photoresist layer on the described oxide-nitride-oxide skin(coating) that is positioned at described second conductor layer;
Described photoresist layer is carried out a dry ecthing procedure with reacting gas of a high-carbon fluorine ratio as an etch mask be positioned at the described oxide-nitride-oxide skin(coating) of described second conductor layer and described second conductor layer till the surface of the described semiconductor substrate that exposes described periphery circuit region to the open air with etching, wherein, after described dry ecthing procedure is finished, on the etching sidewall of described memory array and described periphery circuit region, will form a polymer protective layer to keep etching outline;
Remove described photoresist layer; And
Carry out a wet etch process with a mixed acid solution and a hydrofluoric acid solution to remove described polymer protective layer, wherein, the mixing ratio of described hydrofluoric acid solution is about between 700: 1 to 1500: 1, and the temperature of described mixed acid solution is approximately less than 35 ℃.
7. the method that can avoid oxide loss when removing polymer protective layer as claimed in claim 6 is characterized in that, described wet etch process comprises one at least approximately greater than the flow of 3000cc/min.
8. the method that can avoid oxide loss when removing polymer protective layer as claimed in claim 6 is characterized in that described mixed acid solution comprises an ammoniacal liquor at least.
9. the method that can avoid oxide loss when removing polymer protective layer as claimed in claim 6 is characterized in that described mixed acid solution comprises a hydrogen peroxide at least.
10. the method that can avoid oxide loss when removing polymer protective layer as claimed in claim 6 is characterized in that described mixed acid solution comprises a deionized water at least.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 01125076 CN1400638A (en) | 2001-08-06 | 2001-08-06 | Method for removing residual polymer after etching process and reducing oxide loss |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 01125076 CN1400638A (en) | 2001-08-06 | 2001-08-06 | Method for removing residual polymer after etching process and reducing oxide loss |
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| CN1400638A true CN1400638A (en) | 2003-03-05 |
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| CN 01125076 Pending CN1400638A (en) | 2001-08-06 | 2001-08-06 | Method for removing residual polymer after etching process and reducing oxide loss |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7642152B2 (en) | 2005-09-07 | 2010-01-05 | United Microelectronics Corp. | Method of fabricating spacers and cleaning method of post-etching and semiconductor device |
| CN1933111B (en) * | 2005-09-16 | 2010-06-09 | 联华电子股份有限公司 | Method for producing space wall, cleaning method after etching thereof and semiconductor element |
| US7960289B2 (en) | 2006-12-05 | 2011-06-14 | Canon Kabushiki Kaisha | Etching method, pattern forming process, thin-film transistor fabrication process, and etching solution |
| CN102140645A (en) * | 2010-12-15 | 2011-08-03 | 无锡中微晶园电子有限公司 | Process for cleaning laser-marked silicon slice |
| CN101423761B (en) * | 2007-10-31 | 2011-08-24 | 台湾积体电路制造股份有限公司 | Etching agent and method for controlling recovery of silicon wafer |
| CN104658896A (en) * | 2013-11-19 | 2015-05-27 | 中芯国际集成电路制造(上海)有限公司 | Etching method and semiconductor device |
| CN105280499A (en) * | 2014-06-13 | 2016-01-27 | 台湾积体电路制造股份有限公司 | Method for Semiconductor Device Fabrication |
-
2001
- 2001-08-06 CN CN 01125076 patent/CN1400638A/en active Pending
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7642152B2 (en) | 2005-09-07 | 2010-01-05 | United Microelectronics Corp. | Method of fabricating spacers and cleaning method of post-etching and semiconductor device |
| CN1933111B (en) * | 2005-09-16 | 2010-06-09 | 联华电子股份有限公司 | Method for producing space wall, cleaning method after etching thereof and semiconductor element |
| US7960289B2 (en) | 2006-12-05 | 2011-06-14 | Canon Kabushiki Kaisha | Etching method, pattern forming process, thin-film transistor fabrication process, and etching solution |
| CN101548367B (en) * | 2006-12-05 | 2012-05-16 | 佳能株式会社 | Etching method for amorphous semiconductor oxide using alkaline etching solution |
| CN101423761B (en) * | 2007-10-31 | 2011-08-24 | 台湾积体电路制造股份有限公司 | Etching agent and method for controlling recovery of silicon wafer |
| CN102140645A (en) * | 2010-12-15 | 2011-08-03 | 无锡中微晶园电子有限公司 | Process for cleaning laser-marked silicon slice |
| CN102140645B (en) * | 2010-12-15 | 2012-07-11 | 无锡中微晶园电子有限公司 | Process for cleaning laser-marked silicon slice |
| CN104658896A (en) * | 2013-11-19 | 2015-05-27 | 中芯国际集成电路制造(上海)有限公司 | Etching method and semiconductor device |
| CN105280499A (en) * | 2014-06-13 | 2016-01-27 | 台湾积体电路制造股份有限公司 | Method for Semiconductor Device Fabrication |
| CN105280499B (en) * | 2014-06-13 | 2018-08-28 | 台湾积体电路制造股份有限公司 | The manufacturing method of semiconductor devices |
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