Scanning force microscope technique for adhesion distribution measurement

Sasaki, Minoru; Hane, Kazuhiro; Okuma, Shigeru; Torii, Akihiro

doi:10.1116/1.587944

Cited by 11 publications

(4 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Experimental measurements obtained in our lab 1 and elsewhere attribute variance in adhesive force measurements for similar particles and surfaces to surface roughness. [22][23][24] In our prior results and in the predictions shown here, the variaion in the removal force is between 20 and 40% of the adhesive force. 1 Therefore, in practice, to determine the force necessary to remove post-CMP contamination from film surfaces, it may be appropriate to consider the summation of the average adhesive force with a set number of standard deviations in force prediction.…”

Section: Simulation Predictionssupporting

confidence: 54%

Simulation of Particle Adhesion: Implications in Chemical Mechanical Polishing and Post Chemical Mechanical Polishing Cleaning

Cooper

Gupta²,

Beaudoin

2001

J. Electrochem. Soc.

View full text Add to dashboard Cite

We have previously described a model and a simulation approach to describe the adhesive interaction between a particle and a substrate. In this paper, we use the validated simulation to describe the adhesive interaction for alumina particles in contact with dielectric and metal films relevant to chemical mechanical polishing ͑CMP͒ and post-CMP cleaning during integrated circuit manufacture. The descriptions take into account variations in the geometry, surface morphology, and mechanical properties of the particles and substrates. The predictions demonstrate that these three parameters can cause the interaction forces between particles and substrates to vary considerably compared to those for perfect spheres and flat substrates.We have previously described a model and a simulation approach to predict the adhesive interaction between a particle and a substrate. 1-3 This prior work describes particle adhesion as a function of the surface chemistry, morphology, and geometry of the interacting surfaces. It also includes an experimental and theoretical investigation of the adhesion of alumina and polystyrene latex spheres to Cu and SiO 2 substrates in a variety of environments. 1-3 In this paper, we use the validated simulation to provide insight into particle-wafer interactions during chemical mechanical polishing ͑CMP͒ and post-CMP cleaning. CMP and Post-CMP CleaningDuring CMP, a wafer surface is exposed to several different sources of particle contamination. These include (i) slurry particles, commonly micrometer-scale alumina and silica particles, (ii) pieces of the polishing pad used in CMP, primarily polyurethane, and (iii) particles of material removed from the surface during polishing, which may include Cu and copper oxides, W, SiO 2 , and barriers. Ideally all of these forms of contamination need to be minimized. This research focuses on the removal of slurry particle contamination.During CMP, slurry is introduced onto the surface of a wafer from the polishing pad, as seen in Fig. 1. The slurry is an aqueous solution containing abrasive particles. The slurry particles are commonly either alumina or silica, although other types of particles have been used in slurries, including ceria, titania, zirconia, and several different composite abrasives. Following CMP, slurry particles are not completely removed from the wafer's surface. Their adhesion may result from a combination of several phenomena. The first of these is van der Waals ͑vdW͒ forces. These forces are the only ones that are always significant during particle-wafer adhesion. They result in an attractive interaction between slurry particles and film surfaces. Next, chemical or hydrogen bonds can be formed between the slurry particles and the films. Several different effects during CMP can promote bonding of the slurry particles to the film surface. First, the chemical component of the slurry can alter the surface chemistry of the particle and the substrate, causing them to bond to each other. Also, during CMP there is a localized increase in the wafer's ...

show abstract

Section: Simulation Predictionssupporting

confidence: 54%

Simulation of Particle Adhesion: Implications in Chemical Mechanical Polishing and Post Chemical Mechanical Polishing Cleaning

Cooper

Gupta²,

Beaudoin

2001

J. Electrochem. Soc.

View full text Add to dashboard Cite

show abstract

“…The reported adhesion forces were determined from the ‘pull‐off’ regions of the force–distance curves (Cappella & Dietler, 1999) obtained in a number of locations on the sample surface. Considering that these measurements were performed in ambient air, the adhesion force is dominated in this case by the capillary forces brought about by the water layer present on the sample surface (Sasaki et al ., 1995). Furthermore, the thickness of the water layer varies with the hydrophilicity of the surface, in such a way that the more hydrophilic the surface, the thicker the water layer and, therefore, the higher the adhesion force (Suzuki & Mashiko, 1998).…”

Section: Resultsmentioning

confidence: 99%

“…It has long been recognized that the contrast and resolution of the AFM images are strongly influenced by the finite radius of curvature of the probing tip and the interaction forces between the AFM tip and the sample surface (Thundat et al ., 1993; Magonov & Whangbo, 1996). In particular, adhesion forces arising from the water meniscus that forms between tip and sample are dominant when the microscope is used in ambient conditions (Sasaki et al ., 1995) and tend to diminish resolution and image quality due to an increase in the contact area and lateral forces acting on the tip.…”

Section: Introductionmentioning

confidence: 99%

Adhesion artefacts in atomic force microscopy imaging

Paredes¹,

Martı́nez-Alonso²,

Tascón³

2000

Journal of Microscopy

View full text Add to dashboard Cite

Artefacts that affect contrast and arise from adhesion forces in atomic force microscopy images of aramid fibres (both fresh and plasma‐treated) are investigated. It is demonstrated that these stem not only from variations in the chemical composition of the surface but also from certain topographical features (which may appear hidden or enhanced in the images), resulting in changes in the lateral forces that are detected by the cantilever and are comparable to the vertical forces. It is also shown that both types of contribution to the forces can be uncoupled to yield images free from these artefacts, thus allowing more accurate quantitative measurements. These artefactual effects are also generally applicable to many other materials.

show abstract

“…When experimental measurements differ drastically from predictions based upon one of the equilibrium models, the reason most commonly given is nonideal surface morphology (8,9). Recently, there have been a number of investigations into the effect of surface morphology on colloidal forces inside and outside of contact.…”

Section: Introductionmentioning

confidence: 99%