Introduction
The Crystal Scanner™ is an exciting new option for the Pacific Nanotechnology products. With the Crystal Scanner™, imaging nanostructures does not require an expert in the field of scanning probe microscopy. At the core of the Crystal Scanner™ is a new type of force sensor that does not require a complex alignment procedure. It is capable of nanostructure visualization and metrology applications.
With the Nano-R™ fitted with a Crystal Scanner™, engineers and scientists do not have to wait to get the nanoscale images that they require. They can directly measure the images themselves. Companies and research institutions do not have to hire an AFM expert so it costs much less to do nanotechnology research, development and process control.
The Crystal Scanner™ incorporates substantial new developments in the areas of nanonewton force measurements. A Crystal Scanner™ in combination with the stage and software automation in the Nano-R™, creates a new generation of user friendly nanoscale imaging instrumentation. Specifically, the NanoR™ in combination with our Point & Scan Technology™ provides great simplicity of operation.
Point & Scan™ Technology
Point & Scan Technology™ greatly reduces the complexity of the traditional scanning probe microscope. To measure an image, the operator simply launches the system software, and follows the instructions on the computer screen. After only a few steps, an operator is actually seeing an image appear on a computer screen.
Point & Scan Technology™ uses a standard procedure for doing the primary steps that are necessary for measuring nanoscale images. The steps are:
- Select the sample type for imaging.
- Place the sample in the microscope.
- Replace the crystal sensor if necessary.
- Locate the region on the sample for scanning.
- Measure an image.
This same procedure is followed for measuring technical samples such as DVD bits and semiconductor device structures as well as for measuring high-resolution images of nanostructures such as nanotubes, nanoparticles and nanocrystals.
Point & Scan Technology™ is possible because of advances in three fields; the crystal sensor, stage automation, and advanced software.
Crystal Sensor
The force sensor in the Crystal Scanner™ is a small crystal oscillator that has a sharp probe mounted at the end of the crystal. When the probe approaches a surface, the oscillations of the probe are dampened. The amount of dampening is dependent on the force between probe and sample. Software is used to optimize the oscillation frequency and the amount of force between the probe and sample while scanning. No mechanical adjustments are required for the crystal sensor used in the Crystal Scanner™.
 A quartz cross crystal is used in the Nano-R™ Crystal for tracking the forces on a sample. A probe is mounted at one end of the arm of one of the crystals.  Crystal sensor mounted on the zero insertion force module that is used in the Crystal Scanner™. Stage Automation
Advanced stage automation greatly simplifies the operation of the Nano-R™ in combination with the Crystal Scanner™. With the combination of motorized stage optics, sample positioner, and probe sample control, there are no manual adjustments required. Thus, it is simple to introduce a sample, find the location for scanning and then begin scanning.
Crystal Scan™ Software
Crystal Scan™ Software greatly simplifies the operation of the Nano-R™ Crystal Scanner™. After launching the CSS, an operator has to select the type of sample that will be imaged from a menu. Information about the sample type stored in the computer is retrieved and then used for all aspects of measuring an image. For example, the CSS uses information already stored in the computer for setting the scan parameters.
 After launching the crystal scan software, the type of sample that will be scanned is selected.  If required, a video shows how to replace the probe in the scanner.  This screen shows how to place a sample into the stage.  The final screen shows the topography image of the sample that is in the stage.
The CSS software in combination with the stage automation is a very powerful combination. As an example, when the CSS software is launched, the sample stage is moved to a position that is optimal for placing the sample into the microscope. The CSS also places the video optics in the optimal position for locating surface features after a sample is placed in the microscope.
Operators of the microscope have to change samples and probes. To simplify the operation of the Nano-R™ with the Crystal Scanner™, there are several videos integrated in CSS. These videos illustrate how to change a probe and place a sample into the microscope.
Advanced algorithms in the CSS software are used for establishing the quality of a probe in the microscope and for optimizing the scanning parameters. The use of these advanced algorithms for a particular type of sample can be designated in the sample information file.
Advanced Scanner Design For Metrology Measurements
Precise and accurate measurements are assured with the advanced flexure piezo-scanner design used for moving the probe in the Nano-R™ Crystal Scanner™. With the flexure, minimal crosstalk is measured between the X-Y-Z axes and images show little to no background bow.
External calibration sensors are used for monitoring the motion of the flexure scanner. Such sensors are essential for linearizing and calibrating the scanner in the x,y and z axes. These sensors are essential for point and place measurements.
Nano-R™ Crystal Scanner Specifications:
- Range
- X-Y: 65 microns
Z: 8 microns
- Linearity
- X-Y-Z: < 1%
- Cross Talk
- XY: < 1%
ZX: < 2%
ZY: < 2%
- Noise
- Vertical: < .1 nm
Applications
The NanoR™ with the Crystal Scanner™ can measure topography images of all types of samples including technical samples and high-resolution imaging. Technical samples include DVD bits, microlens, paper, gratings, and patterned wafers. High-resolution images of nanostructures such as grains, nanoparticles, nanocrystals, and nanotubes are easily imaged.  High-resolution CFM topography image of magnetic tape. Nanoparticles with diameters of 10 nm are visualized here.  CFM of a test pattern fabricated with electron beam lithography.  CFM image of a piece of commercially available plastic.  Structures at the surface of a patterned wafer imaged with the CFM. 
Atomic terraces of Si imaged with the CFM(Left) Histogram showing single steps.
Interchangeable with the Light Lever AFM
The traditional atomic force microscope uses a light lever for measuring the force of the probe on the surface. Although the light lever is complex and requires alignment for its operation, there are some advantages. The primary advantage is the ability to do material sensing modes such as lateral force microscopy, phase imaging and filed measurements such as magnetic force microscopy and electrical force microscopy (EFM).
The Nano-R™ stage continues to be compatible with the Light Lever Sensor. Changing between the light lever sensor and the crystal sensor takes only a few minutes.
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