• Transactions on Electrical and Electronic Materials
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• v.6 no.4
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• pp.164-168
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• 2005

Effects of high-temperature slurry were investigated on the chemical mechanical polishing (CMP) performance of tetra-ethyl ortho-silicate (TEOS) film with silica and ceria slurries by the surface analysis of X-ray photoelectron spectroscopy (XPS). The pH showed a slight tendency to decrease with increasing slurry temperature, which means that the hydroxyl $(OH^-)$ groups increased in slurry as the slurry temperature increased and then they diffused into the TEOS film. The surface of TEOS film became hydro-carbonated by the diffused hydroxyl groups. The hydro-carbonated surface of TEOS film could be removed more easily. Consequently, the removal rate of TEOS film improved dramatically with increasing slurry temperature.

• International Journal of Precision Engineering and Manufacturing
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• v.9 no.2
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• pp.8-10
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• 2008

Chemical mechanical polishing (CMP) is a very precise planarization technique where a wafer is polished by a slurry-coated pad. A slurry is dropped on the rotating pad surface and is supplied between the wafer and the pad. This research aims at reducing the slurry consumption and removing waste particles quickly from the wafer. To study the roles of grooves, slurry flows were simulated using the volume of fluid method (two-phase model for air and slurry) for pads with no grooves, and for pads with circular grooves.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.274-278
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• 2002

The purpose of this study was to characterize the reaction of Cu surface with Cu slurry and CMP performance as a function of additives in CMP slurry. The polish rate of Cu was dependent on the kind of organic acids added in slurry. It was considered that polish rate of Cu was dependent on the concentration of carboxylates and mean particle size. When the etchant and oxidant were added in slurry, the highest removal rate and lower etch rate were measured at neutral pH. The addition of etchant, oxidant and pH adjustor played key roles of CMP ability in slurry. As the pH increased, polish rate of Cu was increased by the enhanced the mechanical effects due to effective dispersion of slurry particles. Alumina abrasives was more desirable for 1st step slurry because of high removal rate of Cu and high selectivity ratio among TaN and Cu.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.1727-1729
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• 2004

Chemical mechanical polishing (CMP) process has been widely used to planarize dielectric layers, which can be applied to the integrated circuits for sub-micron technology. Despite the increased use of CMP precess, it is difficult to accomplish the global planarization of in the defect-free inter-level dielectrics (ILD). we investigated the performance of $WO_3$ CMP used silica slurry, ceria slurry, tungsten slurry. In this paper, the effects of addition oxidizer on the $WO_3$ CMP characteristics were investigated to obtain the higher removal rate and lower non-uniformity.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.4
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• pp.297-302
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• 2005

Chemical mechanical polishing(CMP) performances can be optimized by several process parameters such as equipment and consumables (pad, backing film and slurry). Pad properties are important in determining removal rate and planarization ability of a CMP process. It is investigated the performance of oxide CMP process using commercial silica slurry after the pad conditioning temperature was varied. Conditioning process with the high temperature made the slurry be unrestricted to flow and be hold, which made the removal rate of oxide film increase. The pad became softer and flexible as the conditioning temperature increases. Then the softer pad provided the better surface planarity of oxide film without defect.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.370-373
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• 2003

As the integrated circuit device shrinks to the smaller dimension, the chemical mechanical polishing (CMP) process was required for the global planarization of inter-metal dielectric(IMD) layer with free-defect. However, as the IMD layer gets thinner, micro-scratches are becoming as major defects. Chemical-Mechanical Planarization(CMP) of conductors is a key process in Damascene patterning of advanced interconnect structure. The effect of alternative commerical slurries pads, and post-CMP cleaning alternatives are discuess, with removal rate, scratch dentisty, surface roughness, dishing, erosion and particulate density used as performance metrics. Electroplated copper depostion is a mature process from a historical point of view, but a very young process from a CMP persperspective. While copper electrodepostion has been used and stuidied for dacades, its application to Cu damascene wafer processing is only now ganing complete accptance in the semiconductor industry. The polishing mechanism of Cu CMP process has been reported as the repeated process of passive layer formation by oxidizer and abrasion action by slurry abrasives. however it is important to understand the effect of oxidizer on copper pasivation layer in order to obtain higher removal rate and non-uniformity during Cu-CMP process. In this paper, we investigated the effects of oxidizer on Cu-CMP process regarding the additional volume of oxidizer.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05b
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• pp.34-37
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• 2001

As the integrated circuit device shrinks to smaller dimensions, chemical mechanical polishing (CMP) process was required for the global planarization of inter-metal dielectric (IMD) layer with free-defect. However, as the inter-metal dielectrics (IMD) layer gets thinner, micro-scratches are becoming as major defects. Micro-scratches are generated by agglomerated slurry, solidified and attached slurry in pipe line of slurry supply system. To prevent agglomerated slurry particle from inflow, we installed 0.5${\mu}m$ POU (point of use) filter, which is depth-type filter and has 80% filtering efficiency for the $1.0{\mu}m$ size particle. In this paper, we studied the relationship between defect generation and pad count to understand the exact efficiency of the slurry filtration, and to find out the appropriate pad usage. Our preliminary results showed that it is impossible to prevent defect-causing particles perfectly through the depth-type filter. Thus, we suggest that it is necessary to optimize the flow rate of slurry to overcome depth type filters weak-point, and to install the high spray of de-ionized Water (DIW) with high pressure.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.50-53
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• 2003

CMP (chemical mechanical polishing) process remained to solve several problems in deep sub-micron integrated circuit manufacturing process. especially consumables (polishing pad, backing film, slurry, pad conditioner), one of the most important components in the CMP system is the slurry. Among the composition of slurries (buffer solution, bulk solution, abrasive particle, oxidizer, inhibitor, suspension, antifoaming agent, dispersion agent), the abrasive particles are important in determining polish rate and planarization ability of a CMP process. However, the cost of abrasives is still very high. So, in order to reduce the high COO (cost of ownership) and COC (cost of consumables) in this paper, we have collected the silica abrasive powders by filtering after subsequent CMP process for the purpose of abrasive particle recycling. And then, we have studied the possibility of recycle of reused silica abrasive through the analysis of particle size and hardness. Also, we annealed the collected abrasive powders to promote the mechanical strength of reduced abrasion force. Finally, we compared the CMP characteristics between self-developed KOH-based silica abrasive slurry and original slurry. As our experimental results, we obtained the comparable removal rate and good planarity with commercial products. Consequently, we can expect the saving of high cost slurry.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.118-118
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• 2008

The oxide CMP has been applied to interlayer dielectric(ILD) and shallow trench isolation (STI) in chip fabrication. Recently the slurry used in oxide CMP being changed from silica slurry to ceria (cerium dioxide) slurry particularly in STI CMP, because the material selectivity of ceria slurry is better than material selectivity of silica slurry. Moreover, the ceria slurry has good a planarization efficiency, compared with silica slurry. However ceria abrasives make a material removal rate too high at the region of wafer center. Then we focuses on why profile of material removal rate is convex. The material removal rate sharply increased to 3216 $\AA$/min by $4^{th}$ run without conditioning. After $4^{th}$ run, material removal rate converged. Furthermore, profile became more convex during 12 run. And average material removal rate decreased when conditioning process is added to end of CMP process. This is due to polishing mechanism of ceria. Then the ceria abrasive remains at the pad, in particular remains more at wafer center contacted region of pad. The field emission scanning electron microscopy (FE-SEM) images showed that the pad sample in the wafer center region has a more ceria abrasive than in wafer outer region. The energy dispersive X-ray spectrometer (EDX) verified the result that ceria abrasive is deposited and more at the region of wafer center. Therefore, this result may be expected as ceria abrasives on pad surface causing the convex profile of material removal rate.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.37-38
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• 2012