• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1522-1527
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• 2004

In this paper, slurry fluid motion, abrasive particle motion, and effects of groove sizing on the pads are numerically investigated in the 2D geometry. Groove depth is optimized in order to maximized the abrasive effect. The simulation results are analyzed in terms of shear stress on pad, groove and wafer, streamline and velocity vector. The change of groove depth entails vortex pattern change, and consequently affects material removal rate. Numerical analysis is very helpful for disclosing polishing mechanism and local physics.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.1
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• pp.85-90
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• 2003

Removal rate and Within Wafer Non-Uniformity (WIWNU), the most critical issues in Chemical Mechanical Polish (CMP) process, are related to the pressure distribution, wafer shape, slurry flow, mechanical property of pad and etc. Among them, wafer warp generated by other various manufacturing process of wafer may induce the deviation of pressure distribution on the backside of wafer. In the convex shaped wafer the pressure onto the backside of wafer is higher than that of perfectly flat shaped wafer. Besides, such an added pressure is in proportion to the curvature of wafer. That is, the bigger the curvature of wafer becomes the higher the removal rate goes. And the WIWNU is known to be directly related to the pressure distribution on the wafer as well. In other words, the deviation of pressure distribution is in proportion to the WIWNU. In this paper, it is found that the wafer shape may be modified through heating the backside of it and thus properly changed pressure onto the backside of it may improve the WIWNU.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.374-375
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• 2006

The purpose of this paper is to investigate the propriety of biodegradable polymer pad in spite of exchanging from existing polyurethane pad used in CMP(Chemical Mechanical Planarization). Poli 400 of G&P Technology for CMP and Ellipsometer of Rudolph AutoEL-III for measurement were used in this experiment. From this experiment, it is proven that the biodegradable polymer pad is sufficiently suitable in CMP process. Therefore, it is expected that, by using the biodegrable pad CMP manufacturing process, and will be decreased. Especially, wafer scratch can be decreased.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.479-480
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• 2006

The purpose of this paper is to investigate the relationship between CMP(Chemical Mechanical Polishing) characteristics of ITO thin film and friction signal by using the CMP monitoring system. Suba 400 pad and MSW2000 slurry of the Rohm & Haas Co. was used in this experiment to investigate the charateristics of ITO CMP. From this experiment, it is proven that the coefficient of friction is related to uniformity of the removal rate of the ITO thin film. Therefore, the prediction of polishing result would be possible by measuring friction signal.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.501-504
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• 1999

In the shallow trench isolation(STI) chemical mechanical polishing(CMP) process, the key issues are the optimized thickness control within- wafer-non-uniformity, and the possible defects such as nitride residue and pad oxide damage. These defects after STI CMP process were discussed to accomplish its optimum process condition. To understand its optimum process condition, overall STI related processes including reverse moat etch, trench etch, STI filling and STI CMP were discussed. It is represented that the nitride residue can be occurred in the condition of high post CMP thickness and low trench depth. In addition there are remaining oxide on the moat surface after reverse moat etch. It means that reverse moat etching process can be the main source of nitride residue. Pad oxide damage can be caused by over-polishing and high trench depth.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.5
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• pp.32-37
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• 2004

Polishing processes are widely used in the glass, optical, die and semiconductor industries. Chemical Mechanical Polishing (CMP) especially is becoming one of the most important ULSI processes for the 0.25m generation and beyond. CMP is conventionally carried out using abrasive slurry and a polishing pad. But the surface of the pad has irregular pores, so there is non-uniformity of slurry flow and of contact area between wafer and the pad, and glazing occurs on the surface of the pad. This paper introduces the basic concept and fabrication technique of the next generation CMP pad using micro-molding method to obtain uniform protrusions and pores on the pad surface.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.05a
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• pp.759-762
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• 2014

반도체소자의 제조 공정 기술 중 구리패턴을 얻기 위해서 사용하는 화학.기계적 연마(CMP)를 이용한 평탄화와 연마 공정에서 Wafer에 도포된 구리의 두께를 실시간으로 측정하여 정밀하게 제어할 필요가 있는데, 이때 획득되는 센서값을 실제 두께 값으로 환산하는 계산과정에서 오차가 발생할 수 있다. 실제 측정 값에 근사한 값을 얻도록 단순평균을 이용한 방법, 이동 평균, 필터 들을 사용하여 결과를 비교하여 옹고스트롬 단위의 두께를 실시간으로 측정하는 제어 시스템의 편차를 줄이도록 하는 방법의 구현에 대해 기술한다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.539-539
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• 2008

본 논문에서는 투명전도박막의 균일한 표면특성을 확보하기 위해 광역평탄화 공정을 적용하여 투명전도 박막의 표면 거칠기를 연구하였으며 슬러리의 종류에 따른 박막의 연마특성을 연구하였다. 본 실험에서 사용된 ITO 박막은 RF Sputtering에 의해 제작되었고 하부 기판은 석영 Glass가 사용되었다. 광역평탄화를 위한 CMP 공정은 고분자 물질계열의 패드위에 슬러리입자를 공급하고 웨이퍼 캐리어에 하중을 가하며 웨이퍼의 표면을 연마하는 방법으로 가공물을 탄성패드에 누르면서 상대 운동시켜 가공물과 친화력이 우수한 부식액으로 화학적 제거를 함과 동시에 초미립자로 기계적 제거를 하는 것이다. ITO 박막의 평탄화를 위한 공정조건은 Polisher pressure 300 g/$cm^2$, 슬러리 유속 80 ml/min, 플레이튼속도 60 rpm으로 하였다. 위의 조건에 따라 공정을 진행 후 연마특성을 측정하였으며 이때 사용된 슬러리는 산화막에 사용되는 실리카슬러리와 금속연마용 슬러리인 EPL을 사용하였다. 연마율은 실리카 슬러리가 EPL슬러리에 비해 높음을 확인 하였다. CMP 공정에 의해 평탄화를 수행 할 경우 실리카슬러리와 EPL슬러리 모두 CMP전에 비해 돌출된 힐록들이 감소되었음을 알 수 있었다. 비균일도 특성은 모든 슬러리가 양호한 특성을 나타내었다. 평탄화된 박막의 표면과 거칠기 특성은 AFM(XE-200, PSIA Company) 을 이용하여 분석을 하였다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.543-543
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• 2008

반도체 집적회로의 제조 공정 중 CMP 공정이 필수 핵심기술이 되었다. 이처럼 CMP 공정 기술이 다층 배선 구조의 광역 평탄화를 위해서는 매우 효과적이지만 기계적인 연마패드와 화학적인 식각 작용을 하는 슬러리를 이용하여 연마가 진행되므로 공정 결함이 문제시되어 왔다. 그 중에서도, 소모자재의 비용이 CMP 공정비용의 70% 이상을 차지하는 제조단가가 높다는 단점이 있다. 특히 고가의 슬러리가 차지하는 비중이 40% 이상을 넘고 있어, 슬러리 원액의 소모량을 줄이기 위한 연구들이 현재 활발히 연구 중에 있다. 본 논문에서는 새로운 혼합 연마제 슬러리에 대한 CMP 특성을 통해 기존에 상용화된 슬러리의 CMP 특성과 비교 고찰하여 MAS의 우수성을 입증하고, 최적화된 공정기술 연구의 기반으로 활용하고자 실리카 슬러리에 $MnO_2$ 연마제를 혼합하여 연마특성을 비교분석하였고, AFM, EDX, XRD, TEM분석을 통해 그 가능성을 알아보았다.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.8 s.173
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• pp.27-33
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• 2005

Polishing pads play an important role in chemical mechanical polishing(CMP) which has recently been recognized at the most effective method to achieve global planarization. In this paper, we have investigated CMP characteristics as a change of groove density of polishing pads. The parameter $(K_n)$ is proposed to estimate groove density of pad. The $K_n$ is defined as groove area divided by pitch area. As the groove density value increased, removal rate increased to some point and then gradually saturated in case of increasing the groove density excessively. In addition Within wafer non-uniformity(WIWNU) worse as groove density increased excessively, although WIWNU improved as groove density increased. Also the uniformity of temperature of pad surface decreased as the groove density increased. It was because that the cooling effect increased as groove density increased. In other words, increasing the groove density which means the apparent contact area of pad has influence on amount of discharge of slurry during polishing process.