Radiant energy – Inspection of solids or liquids by charged particles
Patent
1997-02-26
1998-09-15
Anderson, Bruce
Radiant energy
Inspection of solids or liquids by charged particles
25044211, H01J 3700
Patent
active
058083022
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a fine positioning apparatus with atomic resolution, in particular for scanning probe techniques or storage devices.
BACKGROUND OF THE INVENTION
One technical field of the invention are scanning probe techniques evolving from the discovery of the Scanning Tunneling Microscope (STM) by H. Rohrer and G. Binnig in 1982. The STM, which is disclosed for example in the patent U.S. Pat. No. 4,343,993, triggered the development of a huge variety of instruments. These instruments are designed to investigate and manipulate surfaces and/or atoms or molecules placed on top of them with atomic resolution, i.e., with resolution from 100 nm down to 0.1 nm. A common feature of scanning probe instruments is a fine tip, the probe, with a radius of curvature at its apex of 100 nm or below. The probe is scanned over the surface of a sample by using coarse and fine positioning units which will be described in detail below. Its in principle a simple to implement technique together with its extreme resolution made the STM and its derivatives up to now widely employed scientific tools when dealing with all kinds of surface analysis and imaging of sub-microscopic phenomena.
Besides the STM, scanning probe techniques include the Atomic Force Microscope (AFM), which was invented by G. Binnig in 1986 (U.S. Pat. No. 4,724,318) and subsequently further developed (see for example: U.S. Pat. No. 5,144,833). Images of magnetic domains have been obtain by Magnetic Force Microscopy, as described by H. J. Mamin et al. in: Appl. Phys. Lett. 55 (1989), pp. 318ff. A Scanning Capacitance Microscope is known from the patent U.S. Pat. No. 5,065,103, a Scanning Acoustic Microscope from U.S. Pat. No. 4,646,573, and a Scanning Thermal Profiler from U.S. Pat. No. 4,747,698. The scanning probe techniques is also used in light microscopes having a resolution not limited by diffraction. In these so-called Scanning Near-field Optical Microscopes, described for example in U.S. Pat. No. 4,604,520, the probe essentially consist of a waveguide for light waves ending in a tiny aperture which either receives or emits light within the proximity of the surface of a sample. For the purpose of this invention, all these as well as related techniques are referred to as scanning probe microscopy (SPM).
However, the SPM crucially depends on an accurate scanning system which provides for positioning and scanning the probe or tip relatively to the surface of a sample. By convention, the directions within a plane parallel to the surface are denoted by `x` and `y`, whereas the direction perpendicular to this plane is commonly referred to as `z-axis`. As is immediately obvious, the scanning system has a decisive impact upon the resolution of the scanning probe device. For achieving atomic resolution , it must be able to perform controllable displacements with an accuracy of 0.1 nm or less with the requirements for the z-direction being more vigorous than those for the other directions. An ideal scanning system for scanning probe devices should combine a large scanning range in the x,y-plane with an accurate control of the position of the tip relative to the sample in all three dimensions, but in particular in z-direction. As both requirements are difficult to fulfill, all known SPM devices apply a two-stage positioning system: a coarse positioner moves the sample close to the probe until the distance ranges can be covered by a fine scanner. The fine scanner alone delivers the required accuracy and thus enables imaging and manipulation with atomic resolution. Many different approaches and techniques have been applied for coarse positioning, including a manual approach using levers or differential springs, a piezo-electric walker mechanism (louse), or a stepping motor coupled to the sample or scanning stage. Magnetic coarse positioners are described for example in the European patent EP-B-0 290 522 and in the US patent U.S. Pat. No. 4,947,042. The most advanced types of coarse positioner, in particular when controlled by interferometry, achieve a p
REFERENCES:
patent: 4947042 (1990-08-01), Nishioka et al.
patent: 5103174 (1992-04-01), Wandass et al.
patent: 5375087 (1994-12-01), Moreland et al.
patent: 5436448 (1995-07-01), Hosaka et al.
Binnig Gerd K.
Haeberle Walter
Rohrer Heinrich
Smith Douglas P. E.
Anderson Bruce
International Business Machines - Corporation
Murray James E.
LandOfFree
Fine positioning apparatus with atomic resolution does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Fine positioning apparatus with atomic resolution, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fine positioning apparatus with atomic resolution will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-91016