List of Figures

1. Biotin
2. Three-dimensional structure of avidin, acquired with x-ray diffraction methods [106]
3. Three-dimensional structure of streptavidin, acquired with x-ray diffraction methods [106]
4. Sketch for streptavidin-biotin bond-force measurements, from [119]. A force is applied to biotin (red) to pull it out of the streptavidin.
5. Asymmetric two-well potential U(x), used in KRAMERS' model. Escape occurs via the forward rate k$^+$ and the backward rate k$^-$. The corresponding activation energies are E$_b^+$ and E$_b^-$. Taken from [61]
6. Conceptual energy landscape of a ligand-receptor bond. The dashed line represents an applied force that lowers the potential barriers and, therefore, the total width of the potential narrows ($x_2 < x_1$). Remade after [91]
7. Sketch of a typical magnetic marker
8. SEM images of three different kinds of magnetic particles
9. Magnetic fields of a rectilinear current, remade after [1]
10. Sketch of a simple setup to manipulate a magnetic marker with a conducting line on a surface.
11. Sectioning of the conducting line for the simulation program showing the magnetic field at point $P$ generated from one section (confer figure 1.9b)
12. Results from the the simulation program. The top images show the defined conducting lines with the direction of the currents, and the bottom images show the normalized magnetic field.
13. Tunneling in metal/insulator/metal (M/I/M) structures, [84]
14. Exchange bias and coercive field of a CoFe layer in dependence on the MnIr thickness. From [124]
15. Sputtering systems used in this thesis
16. Full recorded spectrum of the layer stack TMR-DP15 from the quadrupole mass spectrometer. Because the channels for different masses are not fully separated, some artefacts occur (e.g. the rise of Al at the end of the spectrum is only related to the Si peak).
17. Design of the TMR standard mask.
18. Example for an AGM measurement of magnetic markers.
19. Setup used for the main measurements. Including an optical microscope with a CCD-camera, an IC-socket for the samples and a computer with proprietary developed software.
20. Side view of a sample for all preparation steps
21. Sample inside the IC-Socket. Bonded gold wires connect the design with the socket pins
22. Examples for the electromigration of a conducting line
23. Water is boiling because of an overheating conducting line
24. Splintered glass on top of the conducting lines
25. A 5mA current through the straight conducting line (width = 3.8$\mu$m) attracts the magnetic marker. The images have a size of 63$\mu$m $\times$ 37.8$\mu$m. See the CD for the complete Video.
26. Trapping magnetic markers inside a ring shaped conducting line. See the CD for the complete video.
27. Trapping many magnetic markers inside a ring shaped conducting line, from [85]
28. Manipulation with magnetic and electric fields. A current through the thin and wide lines in the middle generates a magnetic field, and the top and bottom lines are electrodes of a capacitor to create an electric field. See the CD for a complete video.
29. Transportation of single beads, from Wirix-Speetjens [136]
30. Moving magnetic particles to several defined positions with a star like structure.
31. Sketch for the bond-force measurements
32. Sketch for the Sulfur-gold bond measurements
33. Auger measurements of sputtered gold surfaces
34. The sulfur bond cannot be broken with the maximum magnetic field (a), but with an electric field between the outer electrodes, (b) and (c). See the CD for the complete Video.
35. Complete design used for all bond-force measurements. The measurement area is magnified.
36. Bond enthalpy of all bonds between the surface and the magnetic marker. The xDNA strand has a phosphor backbone with a bond enthalpy for the P-O bond of 407kJ/mol. Enthalpy values are from [108,92]
37. Three images of a recorded video. At 73mA two streptavidin markers still bind to the biotin (a). At a current of 74mA, the upper marker is ruptured (b), and at 81mA the lower is ruptured (c). See CD for the complete video.
38. Distributions of the measured bond-forces for streptavidin-biotin (a) and avidin-biotin (b) bonds.
39. Bond-Force dependency on the loading rate for the streptavidin-biotin bond. The values for the atomic force microscopy (AFM) are from [97] and the values for the dynamic force spectroscopy (DFS) are from [91].
40. Bond-Force dependency on the loading rate for the avidin-biotin bond. The values for the atomic force microscopy (AFM) are from [44] and the values for the dynamic force spectroscopy (DFS) are from [91].
41. Three different designs to position single magnetic particles. The design is evolving from (a) to (c). See the CD for complete videos of the positioning experiments.
42. SEM image of the final design.
43. (a) Orthogonal pinning of top to bottom magnetic electrodes. (b) Layer stack used for the TMR sensor.
44. Major loop from the final layer stack of a typical 300$\times$300$\mu$m$^2$ TMR element.
45. Minor loop from the final layer stack of a typical 300$\times$300$\mu$m$^2$ TMR element.
46. I/V measurements of the used layer stack.
47. Side view of all preparation steps for the TMR elements and the manipulation system on top.
48. SEM image of the completed sample.
49. Major loop of a typical 2$\times$2$\mu$m$^2$ TMR element, of the structured sample.
50. I/V measurements of the 2$\times$2$\mu$m$^2$ TMR element.
51. Placement of a single magnetic marker (MICROMOD marker with a diameter of 1.5$\mu$m) into the corner of the positioning structure, right before (a) and after (b) the marker reaches the final position. The images have a size of $86.7 \times 86.7$$\mu$m$^2$. See CD for the complete video.
52. SEM images of well positioned single magnetic markers (MICROMOD, $\varnothing$=1.5$\mu$m).
53. Destruction of the TMR elements.