There are three critical issues that must be addressed to successfully measure AFM images for all applications. They are:

1. Select the optimal probe for the application - The probe must be sharp enough to image the features of interest, and must have a shape such that the measurements are accurate if required.
2. Prepare the sample correctly - The sample must be rigidly mounted in the microscope and materials placed on a surface must be rigidly attached to the surface.
3. Make sure to use the correct mode and scan parameters for the application - Topography images may be measured in contact or vibrating mode depending on the hardness of the sample and the resolution that is required.

In the following sections, applications in several areas of science and technology are presented. In most cases, an entire book would be required to cover all of the detailed information associated with the application. In many cases an image is presented to illustrate the application.

7.1 Physical Science

AFM is rapidly becoming a standard microscopy technique for visualizing and measuring a material's surface structure in the physical sciences. The types of structures that are scanned with the AFM include: surfaces of bulk materials, thin films, and nanostructures that are located on a surface. There are a large number of materials that may be imaged with an AFM, including polymers, ceramics, metals, crystals, and minerals. The scan ranges for imaging in the physical sciences range from a few nanometers all the way up to tens of microns.

7.1.1 Polymer Composites

Since they are electrically insulating, measuring high resolution images of composites is very difficult with an SEM/TEM because the samples must be coated with a conductive layer. An AFM can readily measure images of composite polymers with little or no sample preparation. With techniques such as vibrating phase mode (Section 4.3.2) it is possible to visualize differences in the composition in composite polymers. The image in Figure 7-2 shows the changes in mechanical properties of a polymer material with phase imaging mode. The distribution of materials in the polymer matrix is clearly observed.