Effect of temperature in titanium chemical mechanical planarization

Abstract

The effect of temperature on the tribological and kinetic attributes of Ti chemical mechanical planarization (CMP) was investigated. Results indicated that processes at platen temperatures of 25 and 50 °C behaved similarly in terms of their tribological mechanism. At both temperatures, average coefficient of friction (COF) ranged from 0.19 to 0.41, indicating that boundary lubrication was the dominant tribological mechanism. Results also showed that average COF decreased with increasing platen temperature likely due to softening of pad asperities and lower slurry viscosity at the higher temperature. Due to exponentially accelerated chemical effects, Ti removal rate was higher when platen temperature was set at 50 °C. A two-step modified Langmuir-Hinshelwood model was used to simulate Ti removal rate and the chemical and mechanical rate constants under different polishing conditions. Simulated values of removal rate agreed well with experimental data. Simulated chemical rate to mechanical rate constant ratios suggested that the removal mechanism shifted from a more chemically-controlled to a more mechanicallycontrolled process as platen temperature was raised.

Effect of Pad Surface Micro-Texture on Tribological, Thermal and Kinetic Characterizations during Copper Chemical Mechanical Planarization

“…As the pad-slurrywafer COF values do not vary significantly, the lubrication mechanism can essentially be assumed to be the same for each application; in this case, boundary lubrication is the dominant tribological mechanism. 10,14 When it comes to COF and RR, both pads demonstrate similar general trends. It is evident that Disc A generates higher COF than Disc B at all polishing conditions.…”

“…The simulated copper RRs agreed very well with experimental data as the model successfully captured the non-Prestonian behavior of the process. Mu et al 10 reported kinetic and thermal simulation results of Ti CMP at different polishing conditions. The results showed a shift from chemically to mechanically-controlled removal mechanism when polishing temperature increased.…”

Effect of Abrasive Nanoparticle Concentration on the Tribological, Thermal and Kinetic Attributes of Tungsten Chemical Mechanical Planarization

“…In addition, this behavior seems to be unique to tungsten polishing as it has not been observed when polishing Ti, Cu, Co or SiO 2 films. [22][23][24] The slope of the Arrhenius curve is due to the fact that film ECS Journal of Solid State Science and Technology, 2020 9 024014 characteristics including morphology, density and chemistry (i.e. elemental composition) change as a function of film thickness for the CVD tungsten films.…”

Tribological, Thermal, Kinetic, and Pad Micro-Textural Studies Using Polyphenylene Sulfide Retaining Rings in Interlayer Dielectric Chemical Mechanical Planarization

“…Our research team has successfully shown the utility of traditional Stribeck curves 23 in determining the lubrication mechanisms involved in the pad-slurry wafer interface in CMP. [24][25][26] We have also introduced and shown that the "Stribeck+ curve" provides more useful tribological information while dramatically reducing consumables as well as cutting down on the experimental time compared to traditional means. [27][28][29] The key point that we have emphasized throughout our published work is that the Stribeck+ curve does not assume normal force to be constant throughout the polishing process as we can measure it (along with the shear force) instantaneously.…”