Contents
1 Introduction 1
2 Specular and off-specular reflectometry 7
2.1 Specular reflectometry . . . . 7
2.1.1 Experimental description of reflectometry . . . . 7
2.1.2 Reflectivity from a single interface . . . 10
2.1.3 Parratt’s recursive algorithm . . . 12
2.1.4 Neutron field in a multilayer . . . 13
2.1.5 Robust calculation of neutron field . . . 15
2.2 Off-specular reflectometry . . . 16
2.2.1 Differential scattering cross-section in distorted wave Born approx- imation . . . 19
2.2.2 Scattering from interfacial roughness . . . 22
2.2.3 Low roughness case and self-affine interface . . . 24
2.2.4 Scattering from deviations through the layer . . . 27
3 Full reflectometry 29 3.1 Scaling of specular to off-specular differential cross-section . . . 29
3.2 Absolute intensity of reflectivity . . . 31
3.3 Estimation of off-specular intensity . . . 35
4 Effect of preannealing on a polymer-polymer interface 37 4.1 Irreversible adsorption of macromolecules . . . 37
4.2 Preparation of thin polymer films . . . 38
4.2.1 Chemicals . . . 39
4.2.2 Spin Coating . . . 41
4.2.3 Floating method . . . 42
4.2.4 Ellipsometry . . . 43
4.3 Experimental results . . . 45
4.3.1 Reflectivity model and results . . . 45
4.3.2 In-plane correlation length . . . 48
4.3.3 Top surface . . . 53
4.3.4 Contributions to off-specular intensity . . . 54
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4.4 Outlook and conclusion . . . 57
5 Destabilization of a buried thin polymer film 65 5.1 Introduction . . . 65
5.2 Annealing of a system with thin capping layer . . . 66
5.2.1 Specular reflectivity . . . 66
5.2.2 Off-specular scattering model and results . . . 69
5.3 Annealing of a system with thick capping layer . . . 72
5.3.1 Initiated nucleation of a buried thin film . . . 73
5.3.2 Unstable system of thin and thick capping films . . . 79
5.4 Three layer system and beyond . . . 84
5.5 Outlook . . . 88
6 Conclusion and outlook 91 6.1 Conclusion . . . 91
6.2 Outlook and discussion . . . 92
References 97 A Additional off-specular scattering plots 103 A.1 Preannealed and non-preannealed samples . . . 103
A.2 Bilayer with thin capping layer . . . 107
A.3 Bilayers with thick capping layer . . . 110
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