Detection system for atomic force microscopes

Claim 2

A scanning force microscope device comprising in combination: a. a sensing probe having a substantially reflective surface on one side and a scanning tip on the opposite side, said tip adapted to be positioned adjacent a surface to be scanned; b. illuminating means positionally decoupled from said sensing probe and independent of probe motion for generating a radiant energy beam and for applying said beam to said reflective surface; c. position control means coupled to said sensing probe for moving said scanning tip substantially parallel to a surface to be scanned in a predetermined pattern and for moving said scanning tip orthogonal to the surface to follow the contours of the surface; d. beam positioning means adapted to receive said radiant energy beam from said illuminating means for directing said radiant energy beam to said reflective surface to follow said sensing probe through lateral motion of said probe; and e. detector means adapted to receive the energy beam reflected from said reflective surface and operable in response to movement of said reflected energy beam corresponding to position changes of said sensing probe relative to the surface to be scanned to produce a motion representing signal corresponding to tip movement following the contours of the scanned surface, whereby tip motion in a direction orthogonal to scanning motion results in a series of electrical signals corresponding to and representative of the surface contours of the scanned surface. surface.

Claim 3

The microscope device of claim 1 wherein said illuminating means include a laser.

Claim 4

The microscope device of claim 1 wherein said illuminating means include a lens for focussing said energy beam to said reflective surface.

Claim 5

The microscope device of claim 3 wherein said lens narrowly focuses said radiant energy beam at said scanning probe reflective surface.

Claim 6

The microscope device of claim 1 wherein said detecting means are comprised of at least two photodetecting cells.

Claim 7

The microscope device of claim 1 further including compensating means for correcting for errors at said detection means resulting from lateral movement of said reflective surface.

Claim 8

The microscope device of claim 6 wherein said compensating means include a lens and further include computer means employing software algorithms operable in response to applied detector means signals for compensating for errors arising from scanning tip lateral movement.

Claim 9

The microscope device of claim 1 wherein said beam positioning means include a directing lens and lens moving means independent of said position control means for moving said lens in coordination with tip motion.

Claim 10

The microscope device of claim 1 wherein said beam positioning means include a directing mirror and mirror moving means independent of said positioning means for moving said mirror in coordination with tip motion.

Claim 11

In a scanning force microscope having a sensitive probe with a tip mounted for movement in response to relative vertical distance changes between the sensing tip and a sample surface as the tip moves laterally with respect to the sample surface, apparatus for sensing the vertical movement of the tip relative to the surface being scanned and for creating a signal representative of such vertical movement comprising: a. a reflective surface carried by the sensitive probe tip; b. an energy source positionally decoupled from lateral movement of the sensitive probe tip for emitting a radiant energy beam including focussing means for applying said beam to said reflective surface; c. control means for moving the sensitive probe tip laterally in a raster fashion over the surface of a sample to be scanned and including beam directing means for causing said radiant energy beam to follow the motion of the probe tip; d. driving means for moving the sensitive probe tip in a vertical direction towards and away from the surface of the sample to be examined; and e. detection means positioned to receive said energy beam after reflection from said reflective surface for signalling changes in the beam position, said changes corresponding to and representative of vertical displacement of the sensitive probe tip during raster motion over the sample surface.

Claim 12

In a scanning force microscope having a sensitive probe with a tip mounted for movement in response to relative vertical distance changes between the sensing tip and a sample surface as the tip moves laterally with respect to the sample surface, apparatus for sensing the vertical movement of the tip relative to the surface being scanned and for creating a signal representative of such vertical movement comprising: a. a reflective surface carried by the sensitive probe tip; b. an energy source positionally decoupled from lateral movement of the sensitive probe tip for emitting a radiant energy beam including focussing means for applying said beam to said reflective surface; c. control means for moving the sensitive probe tip laterally in a raster fashion over the surface of a sample to be scanned and including beam directing means for causing said radiant energy beam to follow the motion of the probe tip; d. driving means for moving the sensitive probe tip in a vertical direction towards and away from the surface of the sample to be examined; and e. detection means positioned to receive said energy beam after reflection from said reflective surface for signalling changes in the beam position, said changes corresponding to and representative of vertical displacement of the sensitive probe tip during raster motion over the sample surface.

Claim 13

In a scanning force microscope having a sensitive probe with a tip mounted for movement in response to relative vertical distance changes between the sensing tip and a sample surface as the tip moves laterally with respect to the sample surface, apparatus for sensing the vertical movement of the tip relative to the surface being scanned and for creating a signal representative of such vertical movement comprising: f. a reflective surface carried by the sensitive probe tip; g. an energy source for emitting a radiant energy beam including directing means for applying said beam to said reflective surface; h. control means for moving the sensitive probe tip laterally in a raster fashion over the surface of a sample to be scanned and including beam directing means for causing said radiant energy beam to follow the motion of the probe tip; i. driving means for moving the sensitive probe tip in a vertical direction towards and away from the surface of the sample to be examined; j. means for creating an image of said probe in space at a point in space such that said image does not appear to move when said probe is moved; and k. detection means positioned to receive said energy beam after reflection from said reflective surface for signalling changes in the beam position, said changes corresponding to and representative of vertical displacement of the sensitive probe tip during raster motion over the sample surface.

Claim 14

In a scanning force microscope having a sensitive probe with a tip mounted for movement in response to relative vertical distance changes between the sensing tip and a sample surface as the tip moves laterally with respect to the sample surface, apparatus for sensing the vertical movement of the tip relative to the surface being scanned and for creating a signal representative of such vertical movement comprising: f. a reflective surface carried by the sensitive probe tip; g. an energy source for emitting a radiant energy beam including directing means for applying said beam to said reflective surface; h. control means for moving the sensitive probe tip laterally in a raster fashion over the surface of a sample to be scanned and including beam directing means for causing said radiant energy beam to follow the motion of the probe tip; i. driving means for moving the sensitive probe tip in a vertical direction towards and away from the surface of the sample to be examined; j. means for creating an image of said probe in space at a point in space such that said image does not appear to move when said probe is moved; and k. detection means positioned to receive said energy beam after reflection from said reflective surface for signalling changes in the beam position, said changes corresponding to and representative of vertical displacement of the sensitive probe tip during raster motion over the sample surface.

Claim 15

The microscope device of claim 11 further including compensating means including computer means responsive to the raster location of the sensitive probe tip relative to the sample surface and the distance between said energy source, said control means, the sensitive probe tip and said detection means for correcting beam positional errors.

Claim 16

The microscope device of claim 11 wherein said energy source is a laser.

Claim 17

The microscope device of claim 11 wherein said detecting means include at least two photodetecting cells.

Claim 18

In a scanning force microscope having a sensitive probe with a tip mounted for movement in response to relative vertical distance changes between the sensing tip and a sample surface as the tip moves laterally with respect to the sample surface, apparatus for sensing the vertical movement of the tip relative to the surface being scanned and for creating a signal representative of such vertical movement comprising: a. a reflective surface carried by the sensitive probe tip; b. an energy source for emitting a radiant energy beam including directing means for applying said beam to said reflective surface; c. control means for moving the sensitive probe tip laterally in a raster fashion over the surface of a sample to be scanned and including beam directing means for causing said radiant energy beam to follow the motion of the probe tip; d. driving means for moving the sensitive probe tip in a vertical direction towards and away from the surface of the sample to be examined; e. detection means positioned to receive said energy beam after reflection from said reflective surface for signalling changes in the beam position, said changes corresponding to and representative of vertical displacement of the sensitive probe tip during raster motion over the sample surface; and f. a lens system attached to a deformable ceramic transducer having an axis to create an image of the probe substantially at a selected point along the axis of said transducer at which the probe image appears to be stationary, notwithstanding lateral movement of the probe.

Claim 19

In a scanning force microscope having a sensitive probe with a tip mounted for movement in response to relative vertical distance changes between the sensing tip and a sample surface as the tip moves laterally with respect to the sample surface, apparatus for sensing the vertical movement of the tip relative to the surface being scanned and for creating a signal representative of such vertical movement comprising: a. a reflective surface carried by the sensitive probe tip; b. an energy source for emitting a radiant energy beam including directing means for applying said beam to said reflective surface; c. control means for moving the sensitive probe tip laterally in a raster fashion over the surface of a sample to be scanned and including beam directing means for causing said radiant energy beam to follow the motion of the probe tip; d. driving means for moving the sensitive probe tip in a vertical direction towards and away from the surface of the sample to be examined; e. detection means positioned to receive said energy beam after reflection from said reflective surface for signalling changes in the beam position, said changes corresponding to and representative of vertical displacement of the sensitive probe tip during raster motion over the sample surface; and f. a lens system attached to a deformable ceramic transducer having an axis to create an image of the probe substantially at a selected point along the axis of said transducer at which the probe image appears to be stationary, notwithstanding lateral movement of the probe.

Claim 20

The microscope device of claim 15 wherein said deformable transducer is a cylinder.

Claim 21

The microscope device of claim 15 wherein said selected point is the midpoint of the transducer axis.

Claim 22

The microscope device of claim 15 further including a mirror system attached to a deformable ceramic transducer having an axis to create an image of the probe substantially at a selected point along the axis of said transducer at which the probe image appears to be stationary, notwithstanding lateral movement of the probe.

Claim 23

In a scanning force microscope having a sensitive probe tip mounted for vertical movement in response to relative force changes between the tip and a sample surface as a function of the relative lateral motion of the tip over the sample surface, apparatus for sensing vertical movement of the tip and for creating signals representative of such tip movement corresponding to sample surface contours as a function of lateral position comprising: a. a reflective surface carried by the sensitive probe tip; b. a light source for emitting a radiant energy beam; c. directing means for applying said beam to said reflective surface; d. scanning means for moving the sensitive probe tip in a raster fashion over the sample surface in a plane substantially parallel to the sample surface; e. deploying means for moving the sensitive probe tip in a vertical direction relative to the sample surface; f. steering means for moving said light beam in coordination with the raster motion of the sensitive probe tip; and g. detection means isolated from and independent of probe tip movement responsive to the light beam reflected from said reflective surface for signalling changes in light beam position resulting from movement of the sensitive probe tip, whereby detection mean output signals correspond to and are representative of the vertical motion of the sensitive probe tip and represent the contours of a scanned surface.

Claim 24

In a scanning force microscope having a sensitive probe tip mounted for vertical movement in response to relative force changes between the tip and a sample surface as a function of the relative lateral motion of the tip over the sample surface, apparatus for sensing vertical movement of the tip and for creating signals representative of such tip movement corresponding to sample surface contours as a function of lateral position comprising: a. a reflective surface carried by the sensitive probe tip; b. a light source for emitting a radiant energy beam; c. directing means for applying said beam to said reflective surface; d. scanning means for moving the sensitive probe tip in a raster fashion over the sample surface in a plane substantially parallel to the sample surface; e. deploying means for moving the sensitive probe tip in a vertical direction relative to the sample surface; f. steering means for moving said light beam in coordination with the raster motion of the sensitive probe tip; and g. detection means isolated from and independent of probe tip movement responsive to the light beam reflected from said reflective surface for signalling changes in light beam position resulting from movement of the sensitive probe tip, whereby detection mean output signals correspond to and are representative of the vertical motion of the sensitive probe tip and represent the contours of a scanned surface.

Claim 25

In a scanning force microscope having a sensitive probe tip mounted for vertical movement in response to relative force changes between the tip and a sample surface as a function of the relative lateral motion of the tip over the sample surface, apparatus for sensing vertical movement of the tip and for creating signals representative of such tip movement corresponding to sample surface contours as a function of lateral position comprising: a. a reflective surface carried by the sensitive probe tip; b. a light source for emitting a radiant energy beam; c. directing means for applying said beam to said reflective surface; d. scanning means for moving the sensitive probe tip in a raster fashion over the sample surface in a plane substantially parallel to the sample surface; e. deploying means for moving the sensitive probe tip in a vertical direction relative to the sample surface; f. steering means for moving said light beam in coordination with the raster motion of the sensitive probe tip; g. detection means responsive to the light beam reflected from said reflective surface for signalling changes in light beam position resulting from movement of the sensitive probe tip; and h. means for creating an image of said probe in space at a point in space such that said image does not appear to move when said probe is moved, whereby detection mean output signals correspond to and are representative of the vertical motion of the sensitive probe tip and represent the contours of a scanned surface.

Claim 26

In a scanning force microscope having a sensitive probe tip mounted for vertical movement in response to relative force changes between the tip and a sample surface as a function of the relative lateral motion of the tip over the sample surface, apparatus for sensing vertical movement of the tip and for creating signals representative of such tip movement corresponding to sample surface contours as a function of lateral position comprising: a. a reflective surface carried by the sensitive probe tip; b. a light source for emitting a radiant energy beam; c. directing means for applying said beam to said reflective surface; d. scanning means for moving the sensitive probe tip in a raster fashion over the sample surface in a plane substantially parallel to the sample surface; e. deploying means for moving the sensitive probe tip in a vertical direction relative to the sample surface; f. steering means for moving said light beam in coordination with the raster motion of the sensitive probe tip; g. detection means responsive to the light beam reflected from said reflective surface for signalling changes in light beam position resulting from movement of the sensitive probe tip; and h. means for creating an image of said probe in space at a point in space such that said image does not appear to move when said probe is moved, whereby detection mean output signals correspond to and are representative of the vertical motion of the sensitive probe tip and represent the contours of a scanned surface.

Claim 27

The microscope device of claim 20 including a lens system attached to a deformable ceramic transducer having an axis, said lens system creating said image of the probe substantially at a selected point along the axis of said transducer at which point said probe image appears to be stationary, notwithstanding lateral movement of the probe.

Claim 28

The microscope device of claim 20 wherein said energy source is a laser.

Claim 29

The microscope device of claim 20 wherein said detecting means include at least two photodetecting cells.

Claim 30

The scanning force microscope of claim 20, wherein said steering means include mirror elements.

Claim 31

The scanning force microscope of claim 20, wherein said steering means include lens elements.

Claim 32

The scanning force microscope of claim 20, wherein said steering means include mirror elements and lens elements to direct said light beam from said light source to said reflective surface of the sensitive probe tip.