KR100398834B1 - Slurry composition for chemical mechanical polishing - Google Patents
Slurry composition for chemical mechanical polishing Download PDFInfo
- Publication number
- KR100398834B1 KR100398834B1 KR10-2000-0083650A KR20000083650A KR100398834B1 KR 100398834 B1 KR100398834 B1 KR 100398834B1 KR 20000083650 A KR20000083650 A KR 20000083650A KR 100398834 B1 KR100398834 B1 KR 100398834B1
- Authority
- KR
- South Korea
- Prior art keywords
- polishing
- slurry
- slurry composition
- cmp
- acid
- Prior art date
Links
- 238000005498 polishing Methods 0.000 title claims abstract description 45
- 239000002002 slurry Substances 0.000 title claims abstract description 42
- 239000000203 mixture Substances 0.000 title claims abstract description 16
- 239000000126 substance Substances 0.000 title abstract description 6
- 239000002253 acid Substances 0.000 claims abstract description 12
- 150000004706 metal oxides Chemical class 0.000 claims abstract description 6
- 239000000843 powder Substances 0.000 claims abstract description 5
- 239000008367 deionised water Substances 0.000 claims abstract description 4
- 229910021641 deionized water Inorganic materials 0.000 claims abstract description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 4
- 229910044991 metal oxide Inorganic materials 0.000 claims abstract description 3
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims description 15
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 14
- 229910052721 tungsten Inorganic materials 0.000 claims description 14
- 239000010937 tungsten Substances 0.000 claims description 14
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims description 12
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical group O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 11
- 229910052782 aluminium Inorganic materials 0.000 claims description 11
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 11
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 5
- MVFCKEFYUDZOCX-UHFFFAOYSA-N iron(2+);dinitrate Chemical compound [Fe+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O MVFCKEFYUDZOCX-UHFFFAOYSA-N 0.000 claims description 5
- 239000000377 silicon dioxide Substances 0.000 claims description 5
- 229910001111 Fine metal Inorganic materials 0.000 claims description 4
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims description 4
- 229910045601 alloy Inorganic materials 0.000 claims description 3
- 239000000956 alloy Substances 0.000 claims description 3
- CETPSERCERDGAM-UHFFFAOYSA-N ceric oxide Chemical compound O=[Ce]=O CETPSERCERDGAM-UHFFFAOYSA-N 0.000 claims description 2
- 229910000422 cerium(IV) oxide Inorganic materials 0.000 claims description 2
- 229910052751 metal Inorganic materials 0.000 abstract description 16
- 239000002184 metal Substances 0.000 abstract description 16
- 239000007800 oxidant agent Substances 0.000 abstract description 12
- 239000003002 pH adjusting agent Substances 0.000 abstract description 5
- 238000000034 method Methods 0.000 description 21
- 235000012431 wafers Nutrition 0.000 description 20
- 229910004298 SiO 2 Inorganic materials 0.000 description 7
- 230000000052 comparative effect Effects 0.000 description 7
- 230000001590 oxidative effect Effects 0.000 description 7
- 238000004519 manufacturing process Methods 0.000 description 5
- 239000004065 semiconductor Substances 0.000 description 5
- 238000003860 storage Methods 0.000 description 5
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 4
- 230000003628 erosive effect Effects 0.000 description 4
- 239000011810 insulating material Substances 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 238000001020 plasma etching Methods 0.000 description 4
- 239000000654 additive Substances 0.000 description 3
- 238000005229 chemical vapour deposition Methods 0.000 description 3
- 230000007797 corrosion Effects 0.000 description 3
- 238000005260 corrosion Methods 0.000 description 3
- 230000000704 physical effect Effects 0.000 description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- -1 abrasive particles Chemical class 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 230000002925 chemical effect Effects 0.000 description 2
- VCJMYUPGQJHHFU-UHFFFAOYSA-N iron(3+);trinitrate Chemical compound [Fe+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O VCJMYUPGQJHHFU-UHFFFAOYSA-N 0.000 description 2
- 230000033001 locomotion Effects 0.000 description 2
- 230000007774 longterm Effects 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- SWKHEIHSYWZUJP-UHFFFAOYSA-N 1,3-diazinane-2,4,6-trione Chemical compound O=C1CC(=O)NC(=O)N1.O=C1CC(=O)NC(=O)N1 SWKHEIHSYWZUJP-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- BOTDANWDWHJENH-UHFFFAOYSA-N Tetraethyl orthosilicate Chemical compound CCO[Si](OCC)(OCC)OCC BOTDANWDWHJENH-UHFFFAOYSA-N 0.000 description 1
- HNYOPLTXPVRDBG-UHFFFAOYSA-N barbituric acid Chemical compound O=C1CC(=O)NC(=O)N1 HNYOPLTXPVRDBG-UHFFFAOYSA-N 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000001312 dry etching Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 229910001337 iron nitride Inorganic materials 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09G—POLISHING COMPOSITIONS; SKI WAXES
- C09G1/00—Polishing compositions
- C09G1/02—Polishing compositions containing abrasives or grinding agents
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K3/00—Materials not provided for elsewhere
- C09K3/14—Anti-slip materials; Abrasives
- C09K3/1454—Abrasive powders, suspensions and pastes for polishing
- C09K3/1463—Aqueous liquid suspensions
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F1/00—Etching metallic material by chemical means
- C23F1/10—Etching compositions
- C23F1/14—Aqueous compositions
- C23F1/16—Acidic compositions
- C23F1/30—Acidic compositions for etching other metallic material
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
- H01L21/3205—Deposition of non-insulating-, e.g. conductive- or resistive-, layers on insulating layers; After-treatment of these layers
- H01L21/321—After treatment
- H01L21/32115—Planarisation
- H01L21/3212—Planarisation by chemical mechanical polishing [CMP]
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Organic Chemistry (AREA)
- Materials Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Mechanical Treatment Of Semiconductor (AREA)
Abstract
본 발명은 CMP(chemical mechanical polishing)용 슬러리 조성물에 관한 것으로, 보다 상세하게는 탈이온수, 금속산화물 미분말, 산화제, pH 조절제 및 바비트릭산을 포함하는 CMP용 슬러리 조성물을 제공하며, 본 발명에 의해 금속층과 절연층의 선택비를 높인 CMP용 슬러리 조성물을 제공할 수 있다.The present invention relates to a slurry composition for chemical mechanical polishing (CMP), and more particularly, to a slurry composition for CMP comprising deionized water, a metal oxide fine powder, an oxidizing agent, a pH adjusting agent, and barbitric acid. The slurry composition for CMP which raised the selectivity of a metal layer and an insulating layer can be provided.
Description
본 발명은 반도체 공정에 사용되는 CMP용 슬러리 조성물에 관한 것으로서, 보다 상세하게는 알루미늄, 텅스텐 및 이를 포함하는 합금의 평탄화에 사용되는 CMP(Chemical Mechanical Polishing)용 슬러리 조성물에 관한 것이다.The present invention relates to a slurry composition for CMP used in a semiconductor process, and more particularly, to a slurry composition for chemical mechanical polishing (CMP) used for planarization of aluminum, tungsten and an alloy including the same.
텅스텐과 같은 금속층은 집적회로의 제조과정 중에 반도체 웨이퍼의 전도성 소자들(텅스텐, 알루미늄, 구리 등)의 상호 연결과 접점의 형성 그리고 다른 전도성 소자들과의 연결을 위한 목적으로 사용된다. 최근 들어 집적 회로의 고집적화 및 다층화로 인하여 금속층 및 절연층의 평탄화 방법은 드라이 에칭(Dry Etch) 등의 공정에서 CMP 공정으로 전환되고 있다.Metal layers, such as tungsten, are used for the interconnection of conductive elements (tungsten, aluminum, copper, etc.) and the formation of contacts and for the connection of other conductive elements of semiconductor wafers during the fabrication of integrated circuits. Recently, due to the high integration and multilayer of integrated circuits, the planarization method of the metal layer and the insulating layer has been converted to a CMP process in a process such as dry etching.
직접회로는 다이오드나 트랜지스터들과 같은 디바이스(device)들을 웨이퍼내 또는 표면에 형성시킨 다음, 집적 회로 디바이스 전면에 절연물질을 가하여 제조된다. 이 때, 콘텍 홀(contact hole)이나 비아(via)의 특성은 절연물질에 의해서 결정된다. 비아들은 절연물질을 관통하는 수직적 접속을 하기 위해서 공정 중 전도성 물질로 채워져 웨이퍼 표면상의 디바이스들의 적합한 부분들에 접촉된다. 이 때 알루미늄과 같은 물질은 배선 금속으로서 비아내부를 충분히 채울 수 없기 때문에, 화학적 기상 증착(Chemical Vapor Deposition, CVD)이 적용 가능한 텅스텐으로 비아를 채우는 것이 통상적이다. 그러나 화학적 기상증착을 적용하는 경우, 절연물질을 관통하는 비아 내부뿐만 아니라 절연층 표면 및 알루미늄 배선 위에도 텅스텐층이 형성된다. 이렇게 불필요한 텅스텐층을 제거하기 위해서 반응 이온에칭 (reactive ion etching)법을 적용할 수 있다. 그러나 반응 이온에칭법은 텅스텐을 오버에칭(over etch)함으로써 비아 내부의 텅스텐을 함께 제거하여 그 위에 쌓인 알루미늄 배선과의 콘택이 불량하게 되는 단점이 있다. 또한 반응 이온에칭 공정 후, 웨이퍼에 남아있는 입자들은 디바이스에 치명적인 결함을 발생시킨다. 따라서 이러한 반응 이온에칭 공정을 대신하여 위해 기계적 화학적 연마(CMP)공정이 도입되었다.Integrated circuits are fabricated by forming devices, such as diodes or transistors, in or on a wafer and then applying an insulating material to the front of the integrated circuit device. In this case, the characteristics of the contact hole or the via are determined by the insulating material. The vias are filled with a conductive material during processing to make vertical connections through the insulating material and contact the appropriate portions of the devices on the wafer surface. At this time, since a material such as aluminum cannot fill the inside of the via sufficiently as the wiring metal, it is common to fill the via with tungsten to which chemical vapor deposition (CVD) is applicable. However, when chemical vapor deposition is applied, a tungsten layer is formed not only in the vias penetrating the insulating material but also on the surface of the insulating layer and the aluminum wiring. In order to remove the unnecessary tungsten layer, a reactive ion etching method may be applied. However, the reactive ion etching method has a disadvantage of over-etching tungsten to remove tungsten in the via together, thereby making poor contact with the aluminum wiring stacked thereon. In addition, after the reactive ion etching process, the particles remaining on the wafer cause a fatal defect in the device. Therefore, a mechanical chemical polishing (CMP) process was introduced to replace the reactive ion etching process.
CMP 공정이란 반도체 제조시 반도체 웨이퍼 표면을 연마패드와 슬러리를 이용하여 평탄화시키는 방법을 말한다. 연마패드 및 웨이퍼를 접촉시켜 연마패드와 웨이퍼의 회전 및 직선운동을 혼합한 오비탈 운동을 실시하면서 연마제가 포함된 슬러리를 이용하여 연마하는 공정이다. CMP 공정에 사용되는 슬러리는 크게 물리적 작용을 하는 연마입자와 화학적 작용을 하는 에천트(etchant)등의 화합물로 구성되어 물리적인 작용과 화학적 작용에 의해서 웨이퍼 표면에 노출된 부분을 선택적으로 식각한다. 이 CMP 공정 기술의 발달로 인하여 직접회로 제조에 적용되는 이중 상감(dual damascene)공정 등의 기술 개발이 가능해지게 되었다. 반도체 제조기술의 향상으로 CMP 공정에서 요구되는 연마 속도, 선택도 및 연마 균일도와 같은 연마특성의 수준 또한 점차적으로 엄격해지고 있다.The CMP process refers to a method of planarizing the surface of a semiconductor wafer using a polishing pad and a slurry during semiconductor manufacturing. The polishing pad and the wafer are brought into contact with each other to perform orbital motion by mixing the rotational and linear motions of the polishing pad and the wafer while polishing using a slurry containing an abrasive. The slurry used in the CMP process is composed of compounds such as abrasive particles, which have a large physical effect, and etchant, which has a chemical effect, to selectively etch portions exposed on the wafer surface by physical and chemical effects. The development of the CMP process technology has made it possible to develop a technology such as a dual damascene process applied to integrated circuit manufacturing. As semiconductor manufacturing technology improves, the level of polishing characteristics such as polishing rate, selectivity and polishing uniformity, which are required in the CMP process, are gradually becoming more stringent.
한편 CMP 공정에 사용되는 슬러리는 연마대상에 따라서 절연층을 연마하는 슬러리와 금속층을 연마하는 슬러리로 구분되어지는데, 이는 주로 화학적 작용을 하는 화합물에 차이가 있다. 이 중 금속층 연마용 슬러리에서는 일반적으로 금속 에천트로써 질산, 황산, 질산화 철 또는 과산화 수소 등을 사용하고 있다. 이러한 금속층 연마용 슬러리는 피연마대상인 금속층과 인접한 실리콘 절연층과 선택성이 낮은 경우 디싱(dishing), 에로젼(errosion) 또는 코로젼(corrosion) 등의 현상이 나타나므로 높은 선택비의 달성이 요구되어진다.On the other hand, the slurry used in the CMP process is divided into a slurry for polishing the insulating layer and a slurry for polishing the metal layer according to the polishing target, which is mainly different from the chemical compound. In the slurry for polishing a metal layer, nitric acid, sulfuric acid, iron nitrate or hydrogen peroxide is generally used as the metal etchant. Such a slurry for polishing a metal layer is required to achieve high selectivity because a phenomenon such as dishing, erosion, or corrosion occurs when the silicon insulating layer adjacent to the metal layer to be polished and the selectivity are low. Lose.
본 발명은 상기와 같은 종래기술의 문제점을 해결한 것으로, 슬러리의 화학적 작용을 조절할 수 있는 화학적 첨가제로서 바비트릭 산(barbituric acid)을 사용하여 슬러리의 선택성을 향상시킴으로서 디싱, 에로젼 및 코로젼(corrosion)과 같은 공정상의 문제점을 해결할 수 있는 금속층 연마용 슬러리를 제공한다.The present invention solves the problems of the prior art as described above, by improving the selectivity of the slurry using barbituric acid (barbituric acid) as a chemical additive that can control the chemical action of the slurry (dissipation, erosion and coronation ( Provided is a slurry for polishing a metal layer which can solve process problems such as corrosion.
즉, 본 발명은 금속산화물 미분말 0.1∼10 중량%, 과산화 수소 1∼3 중량%, 질산화철 0.03∼0.1 중량%, 초산 0.05∼0.2 중량%, 바비트릭산 0.01∼0.4 중량, 및 나머지로서 탈이온수를 포함하는 것을 특징으로 하는 CMP용 슬러리 조성물에 관한 것이다.That is, the present invention is 0.1 to 10% by weight fine metal oxide powder, 1 to 3% by weight hydrogen peroxide, 0.03 to 0.1% by weight iron nitrate, 0.05 to 0.2% by weight acetic acid, 0.01 to 0.4% by weight barbic acid, and the rest It relates to a slurry composition for CMP comprising a.
이하에서 본 발명을 보다 상세하게 설명한다.Hereinafter, the present invention will be described in more detail.
본 발명은 텅스텐, 알루미늄 또는 이들이 포함하는 합금으로 이루어진 금속층을 연마하는 슬러리의 제조방법에 관한 것이다.The present invention relates to a method for producing a slurry for polishing a metal layer made of tungsten, aluminum or an alloy containing them.
일반적으로 CMP 공정에 적용되는 슬러리는 물리적 작용을 하는 연마제와 화학적 작용을 하는 화합물을 포함한다. 물리적 작용을 하는 연마제로는 주로 금속미분말이 사용되며 보다 구체적으로는 실리카, 알루미나, 세리아, 티타니아 또는 이들의 혼합물 등을 사용할 수 있다. 화학적 작용을 하는 화합물에는 연마대상인 금속층을 산화시키는 역활을 하는 산화제과 pH 조절제 등이 있고, 필요시 적절한 첨가제가 추가로 첨가될 수 있다. 이러한 첨가제로는 예를 들어 코로젼 억제를 위해 첨가되는 벤조트리아졸(Benxotriaxole) 등이 있다.Generally, the slurry applied to the CMP process includes a compound which chemically reacts with an abrasive which has a physical action. A fine metal powder is mainly used as the abrasive, and more specifically, silica, alumina, ceria, titania, or a mixture thereof may be used. Chemically acting compounds include an oxidizing agent and a pH adjusting agent, which serve to oxidize the metal layer to be polished, and an appropriate additive may be further added if necessary. Such additives include, for example, Benxotriaxole, which is added for suppressing coronation.
일반적으로 연마용 슬러리에 첨가되는 산화제로는 한 종류의 물질만을 사용하는 단일 산화제와 2종 이상의 물질을 복합적으로 사용하는 복합산화제가 있다. 단일 산화제를 사용하는 경우 산화제에 의해 웨이퍼 표면이 산화되면서 산화막이 동시에 형성되기 때문에 연마효율이 떨어지게 된다. 그러나 복합 산화제를 첨가한 경우 이러한 산화막 형성을 감소시킬 수 있으므로 단일산화제를 사용하는 경우보다 연마효율이 향상된다. 따라서 본 발명의 산화제로는 복합산화제를 사용하는 것이 바람직하며, 보다 구체적으로는 과산화 수소(hydrogen peroxide)와 질산화 철(ferric nitrate)을 함께 사용하는 것이 바람직하다. 이 경우 질산화 철이 산화하면서 과산화 수소에 의해 형성된 산화막을 제거하기 때문에 연마효율을 보다 높일 수 있다.In general, oxidants added to the polishing slurry include a single oxidant using only one type of material and a complex oxidant using two or more types of materials in combination. In the case of using a single oxidant, polishing efficiency is lowered because the oxide film is formed at the same time as the wafer surface is oxidized. However, the addition of the composite oxidant can reduce the formation of the oxide film, thereby improving the polishing efficiency than using the single oxidant. Therefore, it is preferable to use a complex oxidant as the oxidant of the present invention, and more specifically, it is preferable to use hydrogen peroxide and ferric nitrate together. In this case, since the oxide film formed by hydrogen peroxide is removed while the iron nitride is oxidized, the polishing efficiency can be further improved.
본 발명의 pH 조절제는 초산(acetic acid), 질산(nitiric acid) 또는 황산(sulfuric acid) 등을 사용할 수 있다. 질산화 철이 산화제로 첨가되는 경우에는 형성된 Fe2+이온을 안정화시키기 위해서는 초산을 사용하는 것이 보다 바람직하다.The pH adjusting agent of the present invention may be used acetic acid, nitiric acid or sulfuric acid. When iron nitrate is added as an oxidizing agent, it is more preferable to use acetic acid to stabilize the formed Fe 2+ ions.
본 발명의 연마용 조성물의 pH는 상기와 같은 pH 조절제를 이용하여 4 이하로 조절하는 것이 바람직한데, 이는 연마대상이 텅스텐 또는 알루미늄인 경우 일반적으로 pH가 4 이하이거나 8 이상인 조건에서 이온상태로 존재할 수 있으므로 연마가 효율적으로 수행될 수 있기 때문이다. 그러나 pH가 8 이상인 경우에는 절연층으로 사용되는 실리콘이 함께 에칭되면서 선택비가 떨어지는 문제점이 발생한다. 또한 연마용 조성물의 저장안정성을 유지하기 위해서는 연마제로 사용되는 물질의 등전위점(isoelectric point)과 절대값에 차이가 많아야 한다. 실리카는 pH 약 3 내지 4의 범위에서, 알루미나는 pH 약 4에서 등전위점을 가지고 있는 것으로 알려져 있다. 그러므로 실리카나 알루미나를 연마제로서 포함하는 슬러리의 경우에는 pH를 약 1에서 3 정도로 조절하는 것이 저장 안정성 및 연마속도의 측면에서 볼 때 바람직하다.The pH of the polishing composition of the present invention is preferably adjusted to 4 or less by using a pH adjuster as described above, which is generally present in an ionic state at a pH of 4 or less or 8 or more when the polishing target is tungsten or aluminum. This is because polishing can be performed efficiently. However, when the pH is 8 or more, the silicon used as the insulating layer is etched together, causing a problem that the selectivity falls. In addition, in order to maintain the storage stability of the polishing composition, the difference between the isoelectric point and the absolute value of the material used as the abrasive should be large. Silica is known to have an isoelectric point at a pH in the range of about 3-4 and alumina at a pH of about 4. Therefore, in the case of a slurry containing silica or alumina as an abrasive, adjusting the pH to about 1 to 3 is preferable in view of storage stability and polishing rate.
한편 금속 CMP 공정의 수행시 디싱, 에로젼 등의 억제가 요구되며, 이는 첨가되는 산화제 및 pH 조절제의 첨가량을 조절하여 어느 정도까지는 억제가 가능하나 그 범위에는 한계가 있다. 상기와 같은 문제점들은 절연층과 금속층의 연마속도의 차이에 의해서 발생되는 것으로서 슬러리의 선택비를 향상시킴으로서 해결할 수 있다. 따라서 본 발명에서는 상기와 같은 문제점을 해결하기 위하여 바비트릭산(barbituric acid)을 새로이 첨가하여 슬러리의 선택비를 조절하고 있다. 첨가된 바비트릭 산은 금속층의 연마 종결점 근처에서 콘텍이나 비아들이 위치한 디바이스 등에서 절연층이 노출되었을 때, 절연층을 보호하고 일부 미진하게 제거된 텅스텐 또는 알루미늄이 제거되도록 함으로써 선택비를 향상시키는 역할을 한다. 더불어 제타전위의 절대값을 향상시켜서 슬러리의 저장안정성을 향상시키는 역할도 한다.Meanwhile, when performing the metal CMP process, suppression of dishing, erosion, etc. is required, which may be suppressed to some extent by controlling the amount of the oxidizing agent and the pH adjusting agent to be added, but the range is limited. The above problems can be solved by improving the selectivity of the slurry, which is caused by the difference in polishing rates of the insulating layer and the metal layer. Therefore, in the present invention, in order to solve the above problems, a new addition of barbituric acid is used to adjust the selectivity of the slurry. The added barbitic acid serves to improve selectivity by protecting the insulating layer and removing some poorly removed tungsten or aluminum when the insulating layer is exposed, such as in a device where contacts or vias are located near the polishing end of the metal layer. do. In addition, it improves the storage stability of the slurry by improving the absolute value of the zeta potential.
한편 상기 바비트릭산이 탈이온수 및 금속산화물 미분말을 포함하는 CMP용 슬러리에 포함된 경우에도 상기와 같이 선택비를 향상시키는 동일한 효과를 가져올 수 있다는 것이 예상되어진다.On the other hand, it is expected that even when the barbitric acid is included in the slurry for CMP containing deionized water and fine metal oxide powder, the same effect of improving the selectivity as described above is expected.
이하 실시예를 들어 본 발명을 보다 구체적으로 설명한다. 하기 실시예들은 예시적 의미를 지니며 본 발명의 보호 범위를 제한하는 것은 아니다.The present invention will be described in more detail with reference to the following Examples. The following examples are intended to be illustrative and do not limit the scope of protection of the present invention.
실시예 1Example 1
시판 Aerosil 90G(Degussa社)50g, 탈이온수 948.25g, 질산화철 0.5g, 초산 0.75g 및 바비트릭산 0.5g을 2L의 폴리에틸렌 플라스크에 투입하여 2,000rpm의 속도로 2시간 동안 교반시킨 후 고압 분산방법을 이용하여 1,2000psi에서 1회 분산시켰다. 이렇게 해서 얻어진 슬러리를 1㎛ 뎁스(depth)필터를 이용하여 필터링한 후,과산화수소(50%) 21g을 첨가하여 연마용 슬러리를 제조하였다. 제조된 연마용 슬러리를 사용하여 아래와 같은 조건에서 2분간 연마하였다. 그 결과를 표 1에 나타내었다.50 g of commercially available Aerosil 90G (Degussa), 948.25 g of deionized water, 0.5 g of iron nitrate, 0.75 g of acetic acid and 0.5 g of bibitric acid were added to a 2 L polyethylene flask and stirred at a speed of 2,000 rpm for 2 hours, followed by a high pressure dispersion method. Was dispersed once at 1,2000 psi. The slurry thus obtained was filtered using a 1 μm depth filter, and then 21 g of hydrogen peroxide (50%) was added to prepare a polishing slurry. Using the prepared polishing slurry was polished for 2 minutes under the following conditions. The results are shown in Table 1.
* 연마기 모델 : 6EC(STRASBAUGH社)* Grinding Machine Model: 6EC (STRASBAUGH)
* 연마조건* Polishing condition
- 패드 타입 : IC1000/SubaⅣ Stacked(Rodel社)-Pad Type: IC1000 / SubaⅣ Stacked (Rodel)
- 평탄화 속도(Platen Speed) : 120rpm-Platen Speed: 120rpm
- 퀼 스피드(Quill Speed) : 120rpmQuill Speed: 120rpm
- 압력 : 6psiPressure: 6 psi
- 배압(Back pressure) : 0psiBack pressure: 0psi
- 온도 : 25℃Temperature: 25 ℃
- 슬러리 흐름(Slurry flow) : 150 ㎖/minSlurry flow: 150 ml / min
* 연마대상* Polishing target
- 웨이퍼 1 : 텅스텐이 증착된 6인치 웨이퍼Wafer 1: 6-inch wafer with tungsten
- 웨이퍼 2 : 알루미늄이 증착된 6인치 웨이퍼Wafer 2: 6-inch wafer with aluminum deposited
- 웨이퍼 3 : P-TEOS(poly(tetraethyl-orthosilicate))가 증착된 6인치 웨이퍼Wafer 3: 6-inch wafer deposited with P-TEOS (poly (tetraethyl-orthosilicate))
실시예 2Example 2
상기 실시예 1에서 바비트릭 산을 2.0g 첨가한 것을 제외하고는 실시예 1과동일한 방법으로 슬러리를 제조하여 연마성능을 평가하였다. 그 결과를 표 1에 나타내었다.Except that 2.0 g of the barbic acid was added in Example 1 to prepare a slurry in the same manner as in Example 1 to evaluate the polishing performance. The results are shown in Table 1.
실시예 3Example 3
상기 실시예 1에서 바비트릭 산을 3.5g 첨가한 것을 제외하고는 실시예 1과 동일한 방법으로 슬러리를 제조하여 연마성능을 평가하였다. 그 결과를 표 1에 나타내었다.A slurry was prepared in the same manner as in Example 1 except that 3.5 g of the barbic acid was added in Example 1 to evaluate the polishing performance. The results are shown in Table 1.
실시예 4∼6Examples 4-6
상기 실시예 1∼3에서 금속산화물로 실리카 대신에 알루미나를 사용한 것을 제외하고는 실시예 1∼3과 동일한 방법으로 슬러리를 제조하여 연마성능을 평가하였다. 그 결과를 표 1에 나타내었다.Except for using alumina instead of silica as a metal oxide in Examples 1 to 3 to prepare a slurry in the same manner as in Examples 1 to 3 to evaluate the polishing performance. The results are shown in Table 1.
실시예 7Example 7
상기 실시예 2에서 제조된 슬러리를 6개월간 장기 저장 후 실시예 1과 같은 조건으로 연마성능을 평가하였다. 그 결과를 표 1에 나타내었다.After the long-term storage of the slurry prepared in Example 2 for 6 months, the polishing performance was evaluated under the same conditions as in Example 1. The results are shown in Table 1.
비교예 1Comparative Example 1
상기 실시예 1에서 바비트릭 산을 첨가하지 않은 것을 제외하고는 실시예 1과 동일한 방법으로 슬러리를 제조하여 연마성능을 평가하였다. 그 결과를 표 1에나타내었다.A slurry was prepared in the same manner as in Example 1 except that the biclic acid was not added in Example 1 to evaluate the polishing performance. The results are shown in Table 1.
비교예 2Comparative Example 2
상기 실시예 4에서 바비트릭 산을 첨가하지 않은 것을 제외하고는 실시예 4와 동일한 방법으로 슬러리를 제조하여 연마성능을 평가하였다. 그 결과를 표 1에 나타내었다.A slurry was prepared in the same manner as in Example 4 except for the addition of the barbic acid in Example 4 to evaluate the polishing performance. The results are shown in Table 1.
비교예 3Comparative Example 3
상기 비교예 1에서 제조한 슬러리를 6개월간 장기 저장한 후 동일한 방법으로 연마성능을 평가하였다. 그 결과를 표 1에 나타내었다.After the long-term storage of the slurry prepared in Comparative Example 1 for 6 months, the polishing performance was evaluated in the same manner. The results are shown in Table 1.
* 선택비: 텅스텐 또는 알루미늄의 연마속도와 절연층(SiO2) 연마속도의 비* Selection ratio: Ratio of polishing rate of tungsten or aluminum to polishing rate of insulating layer (SiO 2 )
본 발명에 의해 금속층과 절연층의 선택비가 높은 CMP용 슬러리를 제공하여 슬러리의 선택성을 향상시킴으로서 디싱, 에로젼 및 코로젼(corrosion)과 같은 공정상의 문제점을 해결할 수 있도록 하였다.The present invention provides a CMP slurry having a high selectivity ratio between the metal layer and the insulating layer to improve the selectivity of the slurry, thereby solving process problems such as dishing, erosion, and corrosion.
Claims (7)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR10-2000-0083650A KR100398834B1 (en) | 2000-12-28 | 2000-12-28 | Slurry composition for chemical mechanical polishing |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR10-2000-0083650A KR100398834B1 (en) | 2000-12-28 | 2000-12-28 | Slurry composition for chemical mechanical polishing |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| KR20020054529A KR20020054529A (en) | 2002-07-08 |
| KR100398834B1 true KR100398834B1 (en) | 2003-09-19 |
Family
ID=27687256
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| KR10-2000-0083650A KR100398834B1 (en) | 2000-12-28 | 2000-12-28 | Slurry composition for chemical mechanical polishing |
Country Status (1)
| Country | Link |
|---|---|
| KR (1) | KR100398834B1 (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR19990014245A (en) * | 1997-07-28 | 1999-02-25 | 에이치 제이 귄넬 | Polishing Composition Including Tungsten Etching Inhibitor |
| KR20000062931A (en) * | 1999-03-18 | 2000-10-25 | 니시무로 타이죠 | Aqueous Dispersion, Aqueous Dispersion for Chemical Mechanical Polishing Used for Manufacture of Semiconductor Devices, Method for Manufacture of Semiconductor Devices, and Method for Formation of Embedded Wiring |
| KR20000076877A (en) * | 1999-03-17 | 2000-12-26 | 니시무로 타이죠 | Slurry for using cmp and cmp method |
| KR100310570B1 (en) * | 1997-12-23 | 2001-11-15 | 포만 제프리 엘 | Chemical mechanical polishing slurry for tungsten |
| KR20010109960A (en) * | 2000-06-05 | 2001-12-12 | 윤종용 | Slurry for chemical mechanical polishing metal layer, method of preparing the same, and method of metallization for semiconductor device using the same |
-
2000
- 2000-12-28 KR KR10-2000-0083650A patent/KR100398834B1/en not_active IP Right Cessation
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR19990014245A (en) * | 1997-07-28 | 1999-02-25 | 에이치 제이 귄넬 | Polishing Composition Including Tungsten Etching Inhibitor |
| KR100310570B1 (en) * | 1997-12-23 | 2001-11-15 | 포만 제프리 엘 | Chemical mechanical polishing slurry for tungsten |
| KR20000076877A (en) * | 1999-03-17 | 2000-12-26 | 니시무로 타이죠 | Slurry for using cmp and cmp method |
| KR20000062931A (en) * | 1999-03-18 | 2000-10-25 | 니시무로 타이죠 | Aqueous Dispersion, Aqueous Dispersion for Chemical Mechanical Polishing Used for Manufacture of Semiconductor Devices, Method for Manufacture of Semiconductor Devices, and Method for Formation of Embedded Wiring |
| KR20010109960A (en) * | 2000-06-05 | 2001-12-12 | 윤종용 | Slurry for chemical mechanical polishing metal layer, method of preparing the same, and method of metallization for semiconductor device using the same |
Also Published As
| Publication number | Publication date |
|---|---|
| KR20020054529A (en) | 2002-07-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101335946B1 (en) | CMP slurry composition for tungsten | |
| US7052625B2 (en) | Slurry and use thereof for polishing | |
| JP6137793B2 (en) | Method for chemical mechanical polishing of tungsten | |
| JP2007243209A (en) | Cmp slurry composition for metal wiring | |
| JP2003086548A (en) | Manufacturing method of semiconductor device and polishing liquid therefor | |
| KR20030002479A (en) | Nitride CMP Slurry having Selectivity to Oxide | |
| KR100680509B1 (en) | Metal cmp slurry composition that favor mechanical removal of metal oxides with reduced susceptibility to micro-scratching | |
| KR100398834B1 (en) | Slurry composition for chemical mechanical polishing | |
| KR100725550B1 (en) | Cu CMP Slurry And Cu Polishing Method Using Thereof | |
| KR100497409B1 (en) | Slurry composition for chemical mechanical polishing of metal | |
| JP3927270B2 (en) | Abrasive, polishing method and method for manufacturing semiconductor device | |
| KR100421928B1 (en) | Slurry composition for polishing metal line of semiconductor wafer | |
| KR100432637B1 (en) | CMP slurry for polishing copper wirings | |
| KR100565426B1 (en) | Slurry for chemical and mechanical polishing of Tungsten line | |
| KR100460312B1 (en) | Slurry composition for chemical mechanical polishing of metal lines | |
| KR100673635B1 (en) | Copper cmp slurry | |
| KR100445757B1 (en) | Slurry For Polishing Metal Lines | |
| KR100359216B1 (en) | Slurry for polishing metal layer of semiconductor device | |
| KR100458756B1 (en) | CMP Slurry for Polishing Metal Wirings of Semiconductor Devices | |
| KR100449614B1 (en) | Slurry composition of low erosion for chemical mechanical polishing of metal lines | |
| KR100649859B1 (en) | CMP Slurry for Polishing of Cu Lines | |
| KR100374724B1 (en) | Slurry for polishing metal layer of semiconductor device | |
| KR100516887B1 (en) | Slurry composition for chemical mechanical polishing of metal | |
| KR100660753B1 (en) | Cmp precursor ? slurry for semiconductor manufacturing having high dispersion stability | |
| KR20030035637A (en) | Slurry for chemical and mechanical polishing of Cu lines |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A201 | Request for examination | ||
| E902 | Notification of reason for refusal | ||
| E701 | Decision to grant or registration of patent right | ||
| GRNT | Written decision to grant | ||
| FPAY | Annual fee payment |
Payment date: 20080623 Year of fee payment: 6 |
|
| LAPS | Lapse due to unpaid annual fee |