• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.211-213
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• 1999

In this paper, we documented the controlling oxide removal amount on the pattern wafer using removal rate and removal thickness of blanket wafer. There was the strong correlation relationship for both(correlation factor:0.7109). So, we could confirm the repeatability as applying for STI CMP process from the obtained linear formular. As the result of repeatability test, the difference of calculated polishing time and actual polishing time was 3.48 seconds based on total 50 lots. If this time is converted into the thickness, it is from 104$\AA$ to 167$\AA$. It is possible to be ignored because it is under the process margin.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.172-176
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• 1996

The rapid structural change of ULSI chip includes minimum features, multilevel interconnection and large diameter wafers. Demands for the advanced chip structure necessitates the development of enhanced deposition, etching and planarization techniques. Planarization refers to a process that make rugged surfaces flat and uniform. One of the emerging technologies for planarization is chemical mechanical polishing(CMP). Chemical and mechanical removal actions occur during CMP, and both appear to be closely interrelated. The purpose of this study is the optimal application of the slurry to the various types of device materials during CMP. We investigates the effect of slurry on CMP characteristics for thermal oxide and sputtered Al blanket wafers. Results from the polishing rate and the uniformity of residual film include mechanical and chemical reactions between several set of slurry and work material.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.1068-1071
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• 2001

Recently, the minimum line width shows a tendancy to decrease and the multi-level to increase in semiconductor. Therefore, a planarization technique is needed, which chemical polishing(CMP) is considered as one of the most important process. CMP accomplishes a high polishing performance and a global planarization of high quality. But there are several defects in CMP such as microscratches, abrasive contaminations, and non-uniformity of polished wafer edges. Spin Etching can improve the defects of CMP. It uses abrasive-free chemical solution instead of slurry. Wafer rotates and chemical solution is simultaneously dispensed on a whole surface of the wafer. Thereby chemical reaction is occurred on the surface of wafer, material is removed. On this study, TEOS film is removed by CMP and Spin Etching, the results are estimated at a viewpoint of material removal rate(MRR) and within wafer non-uniformity(WIWNU).

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.1
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• pp.168-172
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• 2013

In 3D wafer-stacking technology, one of the major issues is wafer warpage. Especially, The important reason of warpage has been known due to CTE(Coefficient of Thermal Expansion) mismatch between materials. It was too hard to choose how to make the FE model for blanket structured wafer level 3D packaging, because the thickness of each layer in wafer level 3D packaging was too small (micro meter or nano meter scale) comparing with diameter of wafer (6 or 8 inches). In this study, the FE model using the shell element was selected and simulated by the ANSYS WorkBench to investigate effects of the CTE on the warpage. To verify the FE model, it was compared by experimental results.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.10
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• pp.1535-1540
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• 2001

This study presents the possibility of scratch reduction on wafer in CMP by applying the ultrasonic and megasonic energy into the slurry which might contain large abrasive particles. Experiments were conducted to verify the dispersion ability of agglomerated particles by applying ultrasonic, megasonic waves and analyze the particle distribution of used slurry in case, of sonic energy assisted or none. And the dispersion stability of megasonic waves was investigated through the experiment of stability of the dispersed slurry, Finally, to confirm that the distribution of particles in slurry by ultrasonic waves was actually related to scratches on wafer when CMP was done, tungsten blanket wafer was processed, by CMP to compare and investigate scratches on wafer.

• Transactions on Electrical and Electronic Materials
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• v.2 no.3
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• pp.24-27
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• 2001

The end point of oxide chemical mechanical polishing (CMP) have determined by polishing time calculated from removal rate and target thickness of oxide. This study is about control of oxide removal amounts on the shallow trench isolation (STI) patterned wafers using removal rate and thickness of blanket (non-patterned) wafers. At first, it was investigated the removal properties of PETEOS blanket wafers, and then it was compared with the removal properties and the planarization (step height) as a function of polishing time of the specific STI patterned wafers. We found that there is a relationship between the oxide removal amounts of blanket and patterned wafers. We analyzed this relationship, and the post CMP thickness of patterned wafers could be controlled by removal rate and removal target thickness of blanket wafers. As the result of correlation analysis, we confirmed that there was the strong correlation between patterned and blanket wafer (correlation factor: 0.7109). So, we could confirm the repeatability as applying for STI CMP process from the obtained linear formula. As the result of repeatability test, the differences of calculated polishing time and actual polishing time was about 3.48 seconds. If this time is converted into the thickness, then it is from 104 $\AA$ to 167 $\AA$. It is possible to be ignored because process margin is about 1800 $\AA$.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.481-482
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• 2006

Chemical-mechanical polishing, the dominant technology for LSI planarization, is trending to play an important function in micro-electro mechanical systems (MEMS). However, MEMS CMP process has a couple of different characteristics in comparison to LSI device CMP since the feature size of MEMS is bigger than that of LSI devices. Preliminary CMP tests are performed to understand material removal rate (MRR) with blanket wafer under a couple of polishing pressure and velocity. Based on the blanket CMP data, this paper focuses on the consumable approach to enhance MEMS CMP by the adjustment of slurry and pad. As a mechanical tool, newly developed microstructured (MS) pad is applied to compare with conventional pad (IC 1400-k Nitta-Haas), which is fabricated by micro melding method of polyurethane. To understand the CMP characteristics in real time, in-situ friction force monitoring system was used. Finally, the topography change of poly-si MEMS structures is compared according to the pattern density, size and shape as polishing time goes on.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.4
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• pp.321-326
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• 2005

Chemical mechanical polishing(CMP) process is essential technology to be applied to manufacturing the dielectric layer and metal line in semiconductor devices. It has been known that overpolishing in CMP depends on pattern selectivity as a function of density and pitch, and use of fixed abrasive pad(FAP) is one method which can improve the pattern selectivity. Thus, dishing & erosion defects can be reduced. This paper introduces the manufacturing technique of FAP using hydrophilic polymers with swelling characteristic in water and explains the self-conditioning phenomenon. When applied to tungsten blanket wafers, the FAP resulted in appropriate performance in point of uniformity, material selectivity and roughness. Especially, reduced dishing and erosion was observed in CMP of tungsten pattern wafer with the proposed FAP.

• Journal of the Korean Ceramic Society
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• v.40 no.2
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• pp.167-171
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• 2003

CMP(Chemical Mechanical Planarization) slurry for STI process is made by mechanically synthesized$CeO_2$as abrasive. The abrasive can be stabilized by electrostatic or steric stabilization in aqueous slurry and steric stabilization is more effective for long-term stability. Blanket-type$SiO_2$and $Si_3N_4$ wafers are polished with CMP slurry containing$CeO_2$synthesized in 50$0^{\circ}C$ or $700^{\circ}C$. Removal rate and surface uniformity of$SiO_2$and$Si_3N_4$wafer and selectivity are influenced by synthetic condition of abrasive, suspension stability and pH of slurries.