• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.28 no.11
• /
• pp.1807-1812
• /
• 2004

The application of chemical mechanical polishing(CMP) has a long history. Recently, CMP has been used in the planarization of the interlayer dielectric(ILD) and metal used to form the multilevel interconnections between each layers. Therefore, much research has been conducted to understand the basic mechanism of the CMP process. CMP performed by the down force and the relative speed between pad and wafer with slurry is typical tribo-system. In general, studies have indicated that removal rate is relative to energy. Accordingly, in this study, CMP results will be analyzed by a viewpoint of the friction energy using friction force measurement. The results show that energy would not constant in the same removal rate conditions

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

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.10a
• /
• pp.622-625
• /
• 2004

The CMP monitoring system was newly developed by the aid of friction force measurement, resulting from installation of piezoelectric quartz sensor on R&D polisher. The correlation between friction and CMP results was investigated in terms of tribological aspects by using the monitoring system. Various friction signals were monitored and analyzed by the change of experimental conditions such as pressure, velocity, pad and slurry. First of all, the lubrication regimes were classified with Sommerfeld Number through measuring coefficient of friction in ILD CMP. And then, the removal mechanism of abrasives could be understood through the correlation with removal rate and coefficient of friction. Especially, the amount of material removal per unit sliding distance is directly proportional to the friction force. The uniformity of CMP performances was also deteriorated as coefficient of friction increased.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.5 s.98
• /
• pp.40-47
• /
• 1999

In CMP for semiconductor wafer films, the acceptable within-chip planarity, within-wafer and wafer-to-wafer nonuniformity could be achieved by conditioning. The role of conditioning is to remove continuously polishing residues from pad and to maintain the initial pad surface pores. To reach these requirements, the diamond grits disk has been considered as a conventional conditioner. However, we have investigated many defects as scratch on wafers out of diamond grits shedding, contaminations from bonding materials, and pad pore subsidences by over-conditioning. So, this paper studies the effect of ultrasonic vibration in CMP conditioning as a representative. The effect of ultrasonic vibration was certified through ILD, Metal CMP.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2004.04b
• /
• pp.89-92
• /
• 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 process, 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.

• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.51 no.7
• /
• pp.311-315
• /
• 2002

Chemical mechanical polishing (CMP) process was required for the global planarization of inter-metal dielectric(IMD), inter-level dielectric (ILD) layers of multi-layer interconnections. In this paper, we studied the characteristics of polishing pad, which can apply shallow trench isolation (STI)-CMP process for global planarization of multi-level interconnection structure. Also, we investigated the effects of different sets of polishing pad, such as soft and hard pad. As an experimental result, hard pad showed center-fast type, and soft pad showed edge-fast type. Totally, the defect level has shown little difference, however, the counts of scratch was detected less than 2 on JR111 pad. Through the above results, we can select optimum polishing pad, so we can expect the improvements of throughput and device yield.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2003.05c
• /
• pp.149-153
• /
• 2003

Chemical mechanical polishing (CMP) technology for global planarization of multi-level inter-connection structure has been widely studied for the next generation devices. CMP process has been paid attention to planarized pre-metal dielectric (PMD), inter-layer dielectric (ILD) interconnections. Expecially, shallow trench isolation (STI) used to CMP process on essential. Recently, the direct STI-CMP process without the conventional complex reverse moat etch process has established by using slurry additive with the high selectivity between $SiO_2$ and $Si_3N_4$ films for the purpose of process simplification and n-situ end point detection(EPD). However, STI-CMP process has various defects such as nitride residue, tom oxide and damage of silicon active region. To solve these problems, in this paper, we studied the planarization characteristics using a high selectivity slurry(HSS). As our experimental results, it was possible to achieve a global planarization and STI-CMP process could be dramatically simplified. Also we estimated the reliability through the repeated tests with the optimized process conditions in order to identify the reproducibility of HSS STI-CMP process.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 1999.11a
• /
• pp.263-268
• /
• 1999

Langasite, a new piezoelectric material was polished by CMP(chemical mechanical polishing). To enhance the polishing rate, alumina abrasives were added to commercial ILD1300 slurry which contains silica abrasive. The effect of added alumina 0 the silica slurry on the polishing rate and damage of langasite was investigated, Experimental results show that the polishing rate and roughness increases with increasing added alumina particle size, Crystallinity of the langasite is also lowered by alumina addition.

• Proceedings of the KSME Conference
• /
• 2003.11a
• /
• pp.922-927
• /
• 2003

In this paper, slurry fluid motion, abrasive particle motion, and roles of groove patterns on the pads are numerically investigated in the 2D and 3D geometries. The simulation results are analyzed in terms of experimental removal rate and WIWNU (within wafer non-uniformity) for ILD (inter level dielectric) CMP process. Numerical investigations reveal that the grooves in the pad behave as uniform distributor of abrasive particles and enhance the removal rate by increasing shear stress. Higher removal rate and desirable uniformity are numerically and experimentally observed at the pad with grooves. Numerical analysis is very well matched with experimental results and helpful for understanding polishing mechanism and local physics.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.29 no.4 s.235
• /
• pp.435-440
• /
• 2005

In this paper, slurry fluid motion, abrasive particle motion, and roles of groove patterns on the pads are numerically investigated in the 2D and 3D geometries. The simulation results are analyzed in terms of experimental removal rate and WIWNU (Within Wafer Non-Uniformity) for ILD (Inter Level Dielectric) CMP process. Numerical investigations reveal that the grooves in the pad behave as uniform distributor of abrasive particles and enhance the removal rate by increasing shear stress. Higher removal rate and desirable uniformity are numerically and experimentally observed at the pad with grooves. Numerical analysis is very well matched with experimental results and helpful fur understanding polishing mechanism and local physics.