1. 1 12&13/05/2005 Review Meeting More Moore_SP3-WP CONSORTIUM CONFIDENTIAL LTM contribution to SP3-WP6 Two tasks: 1.Thermal characterization of ultra thin resist films (D 3.6.1.3.1) 2.Spin Coating and bake modeling for Ultra thin resist films (M 3.6.1.5)

2. 2 12&13/05/2005 Review Meeting More Moore_SP3-WP CONSORTIUM CONFIDENTIAL Thermal characterization of ultra thin resist films (D 3.6.1.3.1) Thermal expansion of thin films followed by ellipsometry Simple homopolymer studied : 1.Polystyrene (PS) 2.PMMA 3.Poly Hydroxystyrene (soluble part of CAR) Studies of Clariant resist : 1.MMC2 (copolymer) 2.MMC3 (CAR) 3.MMC4 (terpolymer)

3. 3 12&13/05/2005 Review Meeting More Moore_SP3-WP CONSORTIUM CONFIDENTIAL Simple polymer 1 : PS (4000 g/mol, Tg ~ 80°C) No variation of Tg Increase of the coefficients of thermal expansion for thickness below 50 nm

4. 4 12&13/05/2005 Review Meeting More Moore_SP3-WP CONSORTIUM CONFIDENTIAL Simple polymer 2 : PMMA (950 000 g/mol, Tg ~ 120°C) Si/PMMA interactions : Tg variations and  are not significative To be continued for thinnest films… No variation of Tg  Influence of the interface effects? 47 nm

5. 5 12&13/05/2005 Review Meeting More Moore_SP3-WP CONSORTIUM CONFIDENTIAL Simple polymer 3 : PHS (8000 g/mol, Tg ~ 170°C) Diminution of the thickness during successive cycles : Degradation or relaxation of PHS chains? Mechanism? Solvent evaporation 1.Kinetic measurements shows compaction even for long time 2.Degradation or chemical modification of PHS with light

6. 6 12&13/05/2005 Review Meeting More Moore_SP3-WP CONSORTIUM CONFIDENTIAL Clariant Resist 1 : MMC2 copolymer hydroxystyrene – butoxystyrene (no PAG) Tg ~ 155°C 1.Diminution of Tg for thickness below 50 nm (significative?) 2.Diminution of the thermal expansion  Contradictory results ?

7. 7 12&13/05/2005 Review Meeting More Moore_SP3-WP CONSORTIUM CONFIDENTIAL Clariant Resist 2 : MMC3 2-methyl-2-adamantol methacrylate (MAdMA)/ Mevalonic lactone methacrylate (contains PAG) Presence of PAG : photo activation of the resist with the spot ligth above Tg Thermal compaction of the film above Tg Compaction

8. 8 12&13/05/2005 Review Meeting More Moore_SP3-WP CONSORTIUM CONFIDENTIAL Clariant Resist 3 : MMC4 Terpolymer hydroxystyrene – styrene-butylmethacrylate (no PAG) Tg ~ 160°C Diminution of the thickness of the films during successive cycles : Photo degradation Cycle 2 for 46 nm and 165 nm films : Tg is not detectable

9. 9 12&13/05/2005 Review Meeting More Moore_SP3-WP CONSORTIUM CONFIDENTIAL Thermal properties of Ultra thin resists films results: 1.No obvious Tg changes with thickness 2.Strong influence of the thickness on thermal expansion of the film 3.Thin layer properties for material if e<100 nm for all materials Important recommendation Ligth filtering to avoid photo degradation

10. 10 12&13/05/2005 Review Meeting More Moore_SP3-WP CONSORTIUM CONFIDENTIAL Spin-Coating modeling Four steps while Spin-coating: 1: Resist deposition 2 : Film generation 3 : Matter ejection predominant for film thinning 4 : Solvant evaporation predominant Composition unchanged

11. 11 12&13/05/2005 Review Meeting More Moore_SP3-WP CONSORTIUM CONFIDENTIAL Film thinning Evaporation at the free surface  concentration gradient and diffusion Hypothesis: wall slows the intermolecular mobility, hence increases the friction parameter between macromolecules

12. 12 12&13/05/2005 Review Meeting More Moore_SP3-WP CONSORTIUM CONFIDENTIAL Spin-Coating Simulation Exemple of the coating of a wafer with a resist

13. 13 12&13/05/2005 Review Meeting More Moore_SP3-WP CONSORTIUM CONFIDENTIAL Post Applied Bake No wall influence On film homogeneity

14. 14 12&13/05/2005 Review Meeting More Moore_SP3-WP CONSORTIUM CONFIDENTIAL Accuracy of the model Without wall effects: the model predicts accurately the spin curves and film compaction while heating With wall effects: No significant differences after Post Applied Bake on the film structure  Friction parameter accurate? Conclusion: Further studies are needed to properly simulate wall effects