1. Don H. Rasmussen Chemical Engineering rasmu@clarkson.edu
Materials Processing
Don H. Rasmussen
Chemical Engineering

2. Outline Characterizing Polymer Surfaces
Probing Concentrated Dispersions
Making ceramic particles
Bonding at interfaces

3. Characterization of Pads for CMP with Saurahb Jain and S. Subramanian
Surface Texture
Geometry effects like dishing and thinning
Surface Hardness
Pad exerted by pad on abrasive particles
Wettability
Slurry availability at wafer surface

5. Schematic of Nanoindenter

6. Force-Displacement Nanoindentation curve
Er (GPa)
Hardness (GPa)
Power Law Coefficients
Execute Fit
P=A(h-hf)m
Contact Depth (nm)
Contact Stiffness (mN/nm) 1.4
Max Force (mN)
Max Depth (nm)
Contact Area (nm^2) E+5
Displacement (nm)
Force (µN)

7. Hardness vs. Indentation Depth

8. Strain Gradient Plasticity Law
Based on molecular kink yield mechanism
developed by Chong and Lam
H0 is the hardness at infinite depth
h0 is a material constant

9. Hardness of OXP3000 Pad

10. Hardness of OXP3000 Pad

11. The constants H0h0 and H0 for Different Pad Surfaces
H0h0 (GPa nm0.5)
H0 (GPa)
OXP-milled
1.898  0.351
 0.038
OXP-smooth
1.702  0.135
 0.013
OXP-side
1.804  0.466
 0.050
OXP-reverse
1.208  0.250
0.026  0.023
Experimental Pad-llr1
0.882  0.160
0.005  0.015
Experimental Pad-llr2
1.166  0.076
0.038  0.007
Experimental Pad-hlr
0.853  0.170
0.007  0.016
OXP-reverse (soaked)
1.652  0.016
 0.015
OXP-smooth (soaked)
2.358  0.252
 0.029

12. Probing Concentrated Dispersions with FODLS with Jingxung Fang and Sridhar Sadasivan
Measurement of Particle Size
Measurement of Particle Concentration

13. The Variational Problem is ill-posed. I.e. Given the
footprints, describe the Tiger.

14. Theory Is
Time
Power Spectrum
AutoCorrelation Function

15. Power Spectrum of Scattered Light
Lorentzian function:
Diffusion Coefficient:
(Stokes-Einstein)
Scattering vector:

16. FODLS System Particles He-Ne Laser Coupler PMT Labview DSP VI Slurries
Computer
Scattered light
Optical fiber
Reflected light

17. Single Scattered Signal
Single Scattering
particles ki
q=ks-ki
|q| = (4np/l)sin(q/2) q
Single Scattered Signal ks
Detector

18. Concentration (wt.%)

19. Concentration (wt.%)

20. Measured Particle Size vs Concentration for
Silica Slurry #2
Diameter by DLS

21. Power Spectrum Density vs Concentration for
Silica Slurry #2

22. Making Alumina Particles with C. Brancewicz et. Al.
Bayer Liquors as a source of nanoscale aluminas

23. Making Ceramic Particles with C. Brancewicz

24. Ternary Phase Diagram for Al(OH)3-NaOH-H2O

26. Amorphous Aggregates
Bayerite

27. Alumina Particles?

28. Deformed ceramic particles?

29. Edax Spectra from Dried Powder

30. Fibrous Amorphous Sodium Aluminate