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Improved Positional Accuracy Of Robots With High Nonlinear Friction Using A Modified Impulse Controller, Stephen Van Duin, Christopher Cook, Zheng Li, Gursel Alici
Improved Positional Accuracy Of Robots With High Nonlinear Friction Using A Modified Impulse Controller, Stephen Van Duin, Christopher Cook, Zheng Li, Gursel Alici
Christopher Cook
This paper presents a modified impulse controller to improve the steady state positioning of a SCARA robot having characteristics of high nonlinear friction. A hybrid control scheme consisting of a conventional PID part and an impulsive part is used as a basis to the modified controller. The impulsive part uses short width torque pulses to provide small impacts of force to overcome static fiction and move a robot manipulator towards its reference position. It has been shown that this controller can greatly improve a robot’s accuracy in position tracking. However, the system in attempting to reach steady state will inevitably …
Synchronous, In-Situ Measurements In Chemical Mechanical Planarization, J. Vlahakis, Chris Rogers, Vincent Manno, Robert White, M. Moinpour, D. Hooper, S. Anjur
Synchronous, In-Situ Measurements In Chemical Mechanical Planarization, J. Vlahakis, Chris Rogers, Vincent Manno, Robert White, M. Moinpour, D. Hooper, S. Anjur
Vincent P. Manno
Achieving device- and wafer-scale planarity in integrated circuit manufacturing is increasingly challenging as device sizes are reduced to and smaller, and wafer sizes are increased from . Hence a better understanding of chemical mechanical planarization (CMP) processes is needed. We report the synchronous, in situ measurement of wafer forces [coefficient of friction (CoF)] and wafer orientation during CMP polishing of BK7 glass wafers and the ex situ measurement of material removal rate (MRR) over a wide range of applied vertical loads and relative rotational velocities. MRR appears to be Prestonian and was significantly reduced by moving the slurry injection location …
In-Situ Measurement Of Pressure And Friction During Cmp Of Contoured Wafers, A. Scarfo, Vincent Manno, Chris Rogers, Sriram Anjur, Mansour Moinpour
In-Situ Measurement Of Pressure And Friction During Cmp Of Contoured Wafers, A. Scarfo, Vincent Manno, Chris Rogers, Sriram Anjur, Mansour Moinpour
Vincent P. Manno
In situ fluid film pressure and interfacial friction measurements during chemical mechanical planarization (CMP) are reported over a range of applied loads (27.6-41.4 kPA or 4-6 psi) and relative pad/wafer velocities . The slurry film pressure beneath contoured test wafers was measured using a novel experimental setup that enables dynamic data collection. The friction data have a repeatability of . The uncertainty of the pressure measurements and the computed down forces were and 20%, respectively. The data indicate that wafer shape, specifically global curvature, is a significant factor in determining the lubrication regime during CMP. Full hydrodynamic lubrication, in which …
Analysis Of Scratches Formed On Oxide Surface During Chemical Mechanical Planarization, Jae-Gon Choi, Y. Prasad, In-Kwon Kim, In-Gon Kim, Woo-Jin Kim, Ahmed Busnaina, Jin-Goo Park
Analysis Of Scratches Formed On Oxide Surface During Chemical Mechanical Planarization, Jae-Gon Choi, Y. Prasad, In-Kwon Kim, In-Gon Kim, Woo-Jin Kim, Ahmed Busnaina, Jin-Goo Park
Jin-Goo Park
Scratch formation on patterned oxide wafers during the chemical mechanical planarization process was investigated. Silica and ceria slurries were used for polishing the experiments to observe the effect of abrasives on the scratch formation. Interlevel dielectric patterned wafers were used to study the scratch dimensions, and shallow trench isolation patterned wafers were used to study the effect of polishing parameters, such as pressure and rotational speed (head/platen). Similar shapes of scratches (chatter type) were observed with both types of slurries. The length of the scratch formed might be related to the period of contact between the wafer and the pad. …
The Effect Of Frictional And Adhesion Forces Attributed To Slurry Particles On The Surface Quality Of Polished Copper, Yi-Koan Hong, Ja-Hyung Han, Tae-Gon Kim, Jin-Goo Park, Ahmed Busnaina
The Effect Of Frictional And Adhesion Forces Attributed To Slurry Particles On The Surface Quality Of Polished Copper, Yi-Koan Hong, Ja-Hyung Han, Tae-Gon Kim, Jin-Goo Park, Ahmed Busnaina
Jin-Goo Park
The effect of frictional and adhesion forces attributed to slurry particles on the quality of copper surfaces was experimentally investigated during copper chemical mechanical planarization process. The highest frictional force of 9 Kgf and adhesion force of 5.83 nN were observed in a deionized water-based alumina slurry. On the other hand, the smallest frictional force of 4 Kgf and adhesion force of 0.38 nN were measured in an alumina slurry containing citric acid. However, frictional (6 Kgf) and adhesion (1 nN) forces of silica particles in the slurry were not significantly changed regardless of the addition of citric acid. These …