System and method of performing scanning probe microscopy on a substrate surface

1. A method of performing scanning probe microscopy on a substrate surface using a scanning probe microscopy system, the system including at least one probe head, the probe head comprising a probe tip arranged on a cantilever and a tip position detector for determining a position of the probe tip along a z-direction transverse to a scanning plane, the method comprising:

moving the probe tip and the substrate surface relative to each other in one or more directions parallel to the scanning plane to position the probe tip at a scanning position on the substrate surface using the probe tip;

measuring, by a displacement encoder, a displacement of said probe tip in said one or more directions, wherein the displacement encoder measures a distance of the probe tip relative to at least one of the group consisting of: a surface of a metrology frame, a surface that is statically connected to a metrology frame, and a two-dimensional optical encoder surface; and

providing a scannable encoder structure fixed relative to the substrate surface and having coded X and Y coordinates, wherein the scannable encoder structure is dimensioned for measuring placement deviations of the probe tip relative to the probe head.

2. The method according to claim 1 wherein the scannable encoder structure forms a fiducial pattern of a grid of fiducial marks in said one or more dimensions; and wherein said grid is dimensioned for measuring placement deviations of the probe tip relative to the probe head by identifying one or more fiducial marks in the fiducial pattern.

3. The method according to claim 1 , wherein said scannable encoder structure is scannable by said probe tip.

4. The method according to claim 1 , wherein the scannable encoder structure is provided by varying at least one of the group consisting of: a local stiffness, a magnetic property, and a material type property.

5. The method according to claim 1 , wherein the scannable encoder structure is fixed to the substrate holder.

6. The method according to claim 1 , wherein the scannable encoder structure is provided on a silicon substrate.

7. The method according to claim 1 , wherein said moving the probe tip and the substrate surface relative to each other is performed by the probe head comprising an actuator for moving the cantilever relative to the probe head in a direction parallel to the scanning plane for performing the scanning of the substrate surface.

8. The method according to claim 1 , wherein the method comprises:

finishing a scan at the scanning position;

moving the probe head to the fiducial pattern to scan a first fiducial mark in the grid of fiducial marks at a first encoder position value;

changing the probe tip;

scanning a second fiducial mark in the grid of fiducial marks; while holding the probe head at the first encoder position value; and

resuming scanning at the scanning position by moving the probe head over a second encoder position value that is the first encoder position value, corrected by a distance of the second fiducial mark relative to the first fiducial mark.

9. A scanning probe microscopy system for performing scanning probe microscopy on a substrate surface using a scanning probe microscopy system, the system including:

a substrate holder for clamping the substrate;

a probe head comprising a probe tip arranged on a cantilever and a tip position detector for determining a position of the probe tip along a z-direction transverse to a scanning plane defined by the substrate holder,

an actuator for moving the probe tip and the substrate holder relative to each other in one or more directions parallel to the scanning plane to position the probe tip at a scanning position on the substrate surface using the probe tip;

a displacement encoder for measuring a displacement of said probe tip in said one or more directions wherein the displacement encoder measures a distance of the probe tip relative to at least one of the group consisting of: a surface of a metrology frame, a surface that is statically connected to a metrology frame, and a two-dimensional optical encoder surface; and

a fiducial pattern fixed relative to the substrate holder, wherein said fiducial pattern has a scannable structure that is scannable by said probe tip, wherein said scannable structure forms a grid of fiducial marks in said one or more dimensions; wherein said grid has coded X and Y coordinates and is dimensioned for measuring placement deviations of the probe tip relative to the probe head by identifying one or more fiducial marks in the fiducial pattern.

10. The system according to claim 9 , wherein the scannable structure has at least one property for facilitating detecting a coded fiducial mark taken from the group consisting of: a varying local stiffness, magnetic property, and a material type property.

11. The system according to claim 9 , wherein the scannable structure is provided on a silicon substrate.

12. The system according to claim 9 , wherein the scannable structure comprises a visual mark.

13. The system according to claim 9 , wherein the scannable structure comprises a orientation mark that facilitates identifying an orientation of the scannable structure relative to the probe tip.

14. The system according to claim 9 , further comprising an actuator for moving the cantilever relative to the probe head in a direction parallel to the scanning plane for performing the scanning of the substrate surface.

15. The scanning probe microscopy system according to claim 9 , further comprising an actuated substrate holder arranged for holding the substrate surface and for moving of the substrate surface in a direction parallel with the scanning plane for performing said scanning of the substrate surface using the probe tip.

16. The system according to claim 9 , further comprising a controller arranged to carry out:

finishing a scan at the scanning position;

moving the probe head to the fiducial pattern to scan a first fiducial mark in the grid of fiducial marks at a first encoder position value; and,

in accordance with changing the probe tip, further performing: scanning a second fiducial mark in the grid of fiducial marks; while holding the probe head at the first encoder position value; and

resuming the scanning position by moving the probe head over a second encoder position value that is the first encoder position value, corrected by the distance of the second fiducial mark relative to the first fiducial mark.