Scratch formation and its mechanism in chemical mechanical planarization (CMP)

Abstract

Chemical mechanical planarization (CMP) has become one of the most critical processes in semiconductor device fabrication to achieve global planarization. To achieve an efficient global planarization for device node dimensions of less than 32 nm, a comprehensive understanding of the physical, chemical, and tribo-mechanical/chemical action at the interface between the pad and wafer in the presence of a slurry medium is essential. During the CMP process, some issues such as film delamination, scratching, dishing, erosion, and corrosion can generate defects which can adversely affect the yield and reliability. In this article, an overview of material removal mechanism of CMP process, investigation of the scratch formation behavior based on polishing process conditions and consumables, scratch formation mechanism and the scratch inspection tools were extensively reviewed. The advantages of adopting the filtration unit and the jet spraying of water to reduce the scratch formation have been reviewed. The current research trends in the scratch formation, based on modeling perspective were also discussed.

Boundary lubrication by adsorption film

“…A deliberate running-in process with controlled wear at the level of asperities of the mating surfaces is beneficial for all of the following machine operations. In some advanced surface finishing processes, such as lapping and chemical mechanical planarization (CMP), a proper wear rate is definitely required for maintaining an acceptable level of productivity [116,117]. In a machinery system, there are a number of contacting interfaces distributed throughout many locations, and different interfaces at the different locations of the machine have different roles and require different desired friction coefficient values.…”

Universal inherent fluctuations in statistical counting of large particles in slurry used for semiconductor manufacturing

“…Let [ s 1 , s 2 ] be an interval where s lies with 95% confidence, i.e., Pr(s 1 ≤ s ≤ s 2 )=0.95. Because Pr(s 1 ≤ s ≤ s 2 ) = Pr((n − 1)s 2 1 /σ 2 ≤ (n − 1)s 2 /σ 2 ≤ (n − 1)s 2 2 /σ 2 ) and the random variable (n − 1)s 2 /σ 2 has a χ 2 -distribution,…”

“…Although numerous material parameters determine material quality, a common critical parameter is the concentration of undesirable particulate matter in materials 1 . As the particulates act as sources of severe manufacturing defects such as micro-scratches 2 , pits 3 , and voids 4 , the concentration of nanoscale to microscale particulates should be accurately measured, controlled, and monitored to prevent such material-induced defects 5 . Various types of particle-sizing and counting instruments have been developed and used, based on light scattering 6 , 7 , light extinction 8 – 10 , and hologram techniques 11 – 13 , which commonly measure the minute volume of liquid samples on the micro- to milli-liter scales.…”

Synthesis and Characterization of SiO2Nanoparticles and Their Efficacy in Chemical Mechanical Polishing Steel Substrate

“…Its properties, including type, size, shape, and concentration of particles, significantly affect CMP performance. Presently, alumina, silica, and ceria are extensively used in CMP slurries as traditional inorganic abrasives [4,5].…”