The Experts below are selected from a list of 129 Experts worldwide ranked by ideXlab platform

Ara Philipossian - One of the best experts on this subject based on the ideXlab platform.

  • effect of conditioner Disc wear on frictional thermal kinetic and pad micro textural attributes of interlayer dielectric and tungsten chemical mechanical planarization
    Japanese Journal of Applied Physics, 2020
    Co-Authors: Juan Cristobal Mariscal, Yasa Sampurno, Hossein Dadashazar, Jeffrey Mcallister, Ara Philipossian
    Abstract:

    A brand-new conventional Diamond Disc was subjected to 32 hours of wear during which SEM images of active Diamonds were taken and pad cut rates were measured. ILD wafers were polished before, midway through, and after the wear test (on a brand-new pad) at varying combinations of pressure and velocity. Tungsten wafers were also polished midway through, and after the 32-hour wear. Polishing was accompanied by pad surface topography analysis via confocal microscopy. The Disc experienced significant Diamond tip micro-wear along with dried slurry accumulation on its substrate causing pad cut rate to drop by a factor of 2. Despite this drastic change, over the duration of the wear test, there were no substantial changes in pad micro-texture, nor ILD or tungsten removal rates indicating the lack of any correlation between pad cut rate and film removal rate during the first 32 hours of wear.

  • Diamond Disc diagnostic method based on dry coefficient of friction measurements
    Electrochemical and Solid State Letters, 2010
    Co-Authors: Anand Meled, Yun Zhuang, Yasa Sampurno, Fransisca Sudargho, Ara Philipossian
    Abstract:

    A method for determining the dry coefficient of friction (COF) of chemical mechanical planarization conditioner Discs for purposes of quality assessment and problem diagnostics was presented. First, two "known good" (K1 and K2) and one "known bad" (K3) Diamond Discs were characterized. Results showed that the COF of K3 was significantly higher than K1 and K2 thus suggesting that the COF can be potentially used as a screening metric for Disc quality. Second, the study confirmed the existence of a correlation between dry COF and the total area of the furrows generated by the active Diamonds such that the COF increased with the total area of the furrows.

  • pad flattening ratio coefficient of friction and removal rate analysis during silicon dioxide chemical mechanical planarization
    Thin Solid Films, 2010
    Co-Authors: Yun Zhuang, Mineo Takaoka, Yoshiyuki Seike, Keiji Miyachi, Takao Nishiguchi, H. Kojima, M. Sugiyama, Ara Philipossian
    Abstract:

    Pad flattening ratio (PFR) was investigated as a non-destructive pad surface analysis method on the IC1000 K-groove pad during silicon dioxide chemical mechanical planarization. The PFR defines as the ratio of the bright area to the total image area. A series of marathon polishing runs were performed under ex-situ Diamond Disc pad conditioning, ex-situ high-pressure micro jet (HPMJ) pad conditioning and no pad conditioning methods where PFR analysis was performed to estimate the amount of pad surface flattening or glazing under these conditions. With no conditioning, PFR increased rapidly to 40% indicating severe glazing. With ex-situ Diamond Disc pad conditioning, PFR remained relatively constant below 12%, suggesting a rough and stable pad surface for polishing, while with ex-situ HPMJ conditioning it increased gradually and stabilized at the value of about 23%. Real-time analysis of friction force and silicon dioxide removal rate showed a clear correlation among the PFR, the coefficient of friction and the removal rate during the silicon dioxide chemical mechanical planarization.

  • characterization of slurry residues in pad grooves for Diamond Disc and high pressure micro jet pad conditioning processes
    Japanese Journal of Applied Physics, 2006
    Co-Authors: Hyosang Lee, Mineo Takaoka, Yoshiyuki Seike, Keiji Miyachi, Yun Zhuang, Ara Philipossian
    Abstract:

    Slurry residues inside pad grooves are quantified by UV-enhanced fluorescence (UVEF) technique for conventional Diamond Disc and high pressure micro jet (HPMJ) pad conditioning methods. Results show that with HPMJ pad conditioning, slurry residues inside pad grooves decrease with time at twice the rate compared to Diamond Disc conditioning. Therefore, this suggests that HPMJ pad conditioning is a viable method to extend pad life and possibly improve wafer-level defectivity.

  • investigation of high pressure micro jet technology as an alternative to Diamond Disc conditioning in ild cmp
    Wear, 2006
    Co-Authors: Darren Denardis, Mineo Takaoka, Yoshiyuki Seike, Keiji Miyachi, Ara Philipossian
    Abstract:

    Abstract The efficacy of an alternative to conventional Diamond conditioning in chemical mechanical planarization (CMP) was evaluated in this study. The high pressure micro jet (HPMJ) system sprays ultra-pure water (UPW) at pressures ranging from 10 to 20 MPa onto a CMP pad to clean the pad of slurry residue, remove embedded slurry particles, and re-establish pad asperities. The system is employed in an ex situ fashion and is compared to in situ and ex situ Diamond conditioning as well as using no conditioning. Real-time frictional force acquisition allows for coefficient of friction (COF) analysis, which indicates the extent of pad wear. Removal rate analysis, SEM imagery, and pad surface profilometry are also used to evaluate HPMJ as an alternative conditioning technology. Removal rates significantly lower than those associated with Diamond conditioning are obtained for the HPMJ system when UPW conditioning is directly followed by polishing. SEM imagery and pad profilimetry indicate these low HPMJ removal rates are due to differences in pad surface chemistry, not pad surface topography. Experiments including a 30 s silicon wafer polish with slurry following HPMJ conditioning to re-establish pad surface chemistry were performed and result in removal rates that are comparable to those obtained using ex situ conditioning. The removal rates obtained using HPMJ conditioning for relative wafer-platen velocities of 0.31 and 0.62 m/s are 8 and 1% higher than those obtained using ex situ Diamond conditioning and 18% lower than those obtained using ex situ Diamond conditioning for 0.93 m/s. The average COF values for HPMJ conditioning using the intermediate silicon wafer polishes are 15% lower than average COF values associated with ex situ Diamond conditioning, suggesting a possible increase in pad life for the HPMJ system.

Yun Zhuang - One of the best experts on this subject based on the ideXlab platform.

  • Diamond Disc diagnostic method based on dry coefficient of friction measurements
    Electrochemical and Solid State Letters, 2010
    Co-Authors: Anand Meled, Yun Zhuang, Yasa Sampurno, Fransisca Sudargho, Ara Philipossian
    Abstract:

    A method for determining the dry coefficient of friction (COF) of chemical mechanical planarization conditioner Discs for purposes of quality assessment and problem diagnostics was presented. First, two "known good" (K1 and K2) and one "known bad" (K3) Diamond Discs were characterized. Results showed that the COF of K3 was significantly higher than K1 and K2 thus suggesting that the COF can be potentially used as a screening metric for Disc quality. Second, the study confirmed the existence of a correlation between dry COF and the total area of the furrows generated by the active Diamonds such that the COF increased with the total area of the furrows.

  • pad flattening ratio coefficient of friction and removal rate analysis during silicon dioxide chemical mechanical planarization
    Thin Solid Films, 2010
    Co-Authors: Yun Zhuang, Mineo Takaoka, Yoshiyuki Seike, Keiji Miyachi, Takao Nishiguchi, H. Kojima, M. Sugiyama, Ara Philipossian
    Abstract:

    Pad flattening ratio (PFR) was investigated as a non-destructive pad surface analysis method on the IC1000 K-groove pad during silicon dioxide chemical mechanical planarization. The PFR defines as the ratio of the bright area to the total image area. A series of marathon polishing runs were performed under ex-situ Diamond Disc pad conditioning, ex-situ high-pressure micro jet (HPMJ) pad conditioning and no pad conditioning methods where PFR analysis was performed to estimate the amount of pad surface flattening or glazing under these conditions. With no conditioning, PFR increased rapidly to 40% indicating severe glazing. With ex-situ Diamond Disc pad conditioning, PFR remained relatively constant below 12%, suggesting a rough and stable pad surface for polishing, while with ex-situ HPMJ conditioning it increased gradually and stabilized at the value of about 23%. Real-time analysis of friction force and silicon dioxide removal rate showed a clear correlation among the PFR, the coefficient of friction and the removal rate during the silicon dioxide chemical mechanical planarization.

  • characterization of slurry residues in pad grooves for Diamond Disc and high pressure micro jet pad conditioning processes
    Japanese Journal of Applied Physics, 2006
    Co-Authors: Hyosang Lee, Mineo Takaoka, Yoshiyuki Seike, Keiji Miyachi, Yun Zhuang, Ara Philipossian
    Abstract:

    Slurry residues inside pad grooves are quantified by UV-enhanced fluorescence (UVEF) technique for conventional Diamond Disc and high pressure micro jet (HPMJ) pad conditioning methods. Results show that with HPMJ pad conditioning, slurry residues inside pad grooves decrease with time at twice the rate compared to Diamond Disc conditioning. Therefore, this suggests that HPMJ pad conditioning is a viable method to extend pad life and possibly improve wafer-level defectivity.

Deivanayagam Kandaswamy - One of the best experts on this subject based on the ideXlab platform.

  • dentinal tubule disinfection with 2 chlorhexidine garlic extract and calcium hydroxide against enterococcus faecalis by using real time polymerase chain reaction in vitro study
    Journal of Conservative Dentistry, 2013
    Co-Authors: Kandaswamy Eswar, Nagendrababu Venkateshbabu, Rajeswari Kalaiselvam, Deivanayagam Kandaswamy
    Abstract:

    Aim: To compare the efficacy of garlic extract with 2% chlorhexidine (CHX) and calcium hydroxide Ca(OH) 2 in disinfection of dentinal tubules contaminated with Enterococcus faecalis by using real-time polymerase chain reaction (PCR). Materials and Methods: Agar diffusion test was done to evaluate the minimum inhibitory concentration of garlic extract against E. faecalis. Forty human extracted mandibular premolar teeth were selected for this study, access cavity was prepared and cleaning and shaping was done. Middle third of the root was cut using a rotary Diamond Disc. The teeth specimens were inoculated with E. faecalis for 21 days. Specimens were divided into four groups---Group 1: 2% CHX, Group 2: Garlic extract, Group 3: Ca(OH) 2 , and Group 4: Saline (negative control). The intracanal medicaments were packed inside the tooth specimens and incubated for 5 days. The dentinal chips were collected at 400 μm depth using a Gates-Glidden drill, following which DNA isolation was done. The specimens were analyzed using real-time PCR. The results were then statistically analyzed using one-way analysis of variance, followed by post hoc Tukey's honestly significant difference (HSD) multiple comparison of means. Results: Threshold cycle (Ct) values of 2% CHX was found to be 32.4, garlic extract to be 27.5, and Ca(OH) 2 to be 25.6. Conclusion: A total of 2% CHX showed the maximum efficacy against E. faecalis, followed by garlic extract and Ca(OH) 2 .

Marco Antonio Bottino - One of the best experts on this subject based on the ideXlab platform.

  • effect of surface conditioning methods on the microtensile bond strength of resin composite to composite after aging conditions
    Dental Materials, 2007
    Co-Authors: Mutlu Ozcan, Silvia Helena Barbosa, Renata Marques De Melo, Graziela Galhano, Marco Antonio Bottino
    Abstract:

    Objectives. This study evaluated the effect of two different surface conditioning methods on the repair bond strength of a bis-GMA-adduct/bis-EMA/TEGDMA based resin composite after three aging conditions. Methods. Thirty-six composite resin blocks (Esthet X, Dentsply) were prepared (5 mm x 6 mm x 6 mm) and randomly assigned into three groups for aging process: (a) immersion in citric acid (pH 3.0 at 37 degrees C, 1 week) (CA); (b) boiling in water for 8h (BW) and (c) thermocycling (x5000, 5-55 degrees C, dwell time: 30s) (TC). After aging, the blocks were assigned to one of the following surface conditioning methods: (1) silica coating (30 mu m SiOx) (CoJet, 3M ESPE) + silane (ESPE-Sil) (CJ), (2) phosphoric acid + adhesive resin (Single Bond, 3M ESPE) (PA). Resin composite (Esthet.X (R)) was bonded to the conditioned substrates incrementally and light polymerized. The experimental groups formed were as follows: Gr1:CA + PA; Gr2:CA + CJ Gr3:BW + PA; Gr4: BW + CJ; Gr5:TC + PA; Gr6: TC + CJ. The specimens were sectioned in two axes (x and y) with a Diamond Disc under coolant irrigation in order to obtain non-trimmed bar specimens (sticks, 10 mm x 1 mm x 1 mm) with 1 mm(2) of bonding area. The microtensile test was accomplished in a universal testing machine (crosshead speed: 0.5 mm min(-1)). Results. The means and standard deviations of bond strength (MPa +/- S.D.) per group were as follows: Gr1: 25.5 +/- 10.3; Gr2: 46.3 +/- 10.1; Gr3: 21.7 +/- 7.1; Gr4: 52.3 +/- 15.1; GrS: 16.1 +/- 5.1; Gr6, 49.6 +/- 13.5. The silica coated groups showed significantly higher mean bond values after all three aging conditions (p <0.0001) (two-way ANOVA and Tukey tests, alpha = 0.05). The interaction effect revealed significant influence of TC aging on both silica coated and acid etched groups compared to the other aging methods (p <0.032). Citric acid was the least aggressive aging medium. Significance. Chairside silica coating and silanization provided higher resin-resin bond strength values compared to acid etching with phosphoric acid followed by adhesive resin applications. Thermocycling the composite substrates resulted in the lowest repair bond strength compared to citric acid challenge or boiling in water. (C) 2006 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Kwun Chung Cheng - One of the best experts on this subject based on the ideXlab platform.

  • use of Diamond Disc cutter in a case of penile strangulation with metal hex nut
    Urology case reports, 2019
    Co-Authors: Kwun Chung Cheng
    Abstract:

    Abstract Penile strangulation by penile constriction devices present uncommonly but require urgent intervention to minimize risk of penile injuries. Non-invasive methods can be attempted and have been proven successful in previous case reports. Surgical intervention with use of cutting tools should be considered if non-invasive means fail. We present a case of penile strangulation by a metal hex nut with successful removal using a Stryker Diamond Disc cutter. Despite residual scarring with retracted prepuce, the patient could void well and had normal erection on follow up at 1 month and 6 months.

  • Use of Diamond Disc cutter in a case of penile strangulation with metal hex nut
    Elsevier, 2019
    Co-Authors: Kwun Chung Cheng
    Abstract:

    Penile strangulation by penile constriction devices present uncommonly but require urgent intervention to minimize risk of penile injuries. Non-invasive methods can be attempted and have been proven successful in previous case reports. Surgical intervention with use of cutting tools should be considered if non-invasive means fail. We present a case of penile strangulation by a metal hex nut with successful removal using a Stryker Diamond Disc cutter. Despite residual scarring with retracted prepuce, the patient could void well and had normal erection on follow up at 1 month and 6 months. Keywords: Constriction, Foreign bodies/ surgery, Penis/injuries, Sexual behaviou