Multimode扫描探针显微镜仪器及原理.ppt

SPM Fundamentals
for the MultiMode
1
Control Mechanisms and Feedback:
2
Feedback and Gains
3
Control Parameters and Feedback
4
Hardware
Review of tapping mode AFM
5
1. Hardware
The MultiMode SPM consists of ponents:
SPM, controller, computer, keyboard, mouse, display monitor and control monitor.
The ponent of the system is the SPM.
ponents:
SPM Head
Scanners
Probe holders
Probes
SPM Head
Illustrates an MM-SPM head with various adjustment knobs. The head and attached X-Y stage are kinematically mated to the scanner via three contact points. A pair of retaining springs secure the head, allowing it to be raised and lowered using adjustment screws threaded through the scanner body.
This picture shows the arrangement of the photodiode elements in the MultiMode head.
The top two elements (A) and the two bottom elements (B) provides a measure of the vertical deflection of the cantilever.
The two left photodiodes (C) and the two right photodiodes (D) provides a measure of the torsional deflection of the cantilever.
Scanners
Figure shows some scanners
which are used for different
sample. Smaller scanners tend
to be more noise-free. Larger
offer wider scans, while requ-
iring extra noise dampening precautions at smaller scan sizes of high resolution.
Note: scanners are interchangeable.
2. When a scanner is changed, the parameter file for the new scanner must also be changed.
Figure depicts the electrode configuration used on a typical scanner piezo tube.
AC voltages applied to the scanner crystal X-Y axes produce a raster-type scan motion represented in Figure .
The sample and mode of SPM to be performed dictate the choice of probe and probeholder.
Probe holders might also be referred to as “tip” or “cantilever” holder. “probe holder” is the preferred nomenclature
holders
Probes
e in a variety of sizes, shapes and materials and are chosen according to the type of imaging being performed.
Most SPM w