Oxford Instruments Cypher SPM, Руководство пользователя

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Cypher SPM
User Guide
ADCs, DACs, BNC connections, and a CrossPoint switch. Advanced users might be interested in
how to control the CrossPoint switch and how to interface with external equipment.
4.1.4 Scanner
The primary function of the scanner is to move the sample relative to the cantilever during imaging
and other measurements such as force curves. There are various scanner modules which excel at
various tasks. The Cypher scanners are “sample scanners”, which means that relative to the room
that the microscope is sitting in, the cantilever is stationary and the sample moves. The scanner is a
modular unit that can be interchanged by the user depending on the application, although at
present there is only a single scanner available. Thus far the scanner modules are based on a flex-
ure design that uses piezoelectric stacks to move the sample up to 30µm in XY and 5µm in Z. The
secondary function of the scanner is to provide motorized course positioning of the cantilever rel-
ative to the sample in the Z-axis. The cantilever holder is a component of the scanner that phys-
ically holds the cantilever during imaging. There are different cantilever holders for air and liquid
operations, and there are also application specific holders for techniques like scanning tunneling
microscopy (STM). Each scanner type has its own family of cantilever holders and other accessor-
ies. The available scanner modules are:
l
The Standard scanner.
l
The Environmental scanner.
4.1.5 Camera
The camera (also called the “view module”) is a user changeable module that provides a top down
optical view of the cantilever and sample. It is comprised of a tube lens, Koehler illumination with
an LED source, and a digital camera. The camera module uses the objective lens in the head to cre-
ate the optical view.
The standard camera module has a bright field reflected light topology and has a 690 µm by 920 µm
field of view with sub-micron resolution. Depending on the application, the view module can be
swapped by the user in about 10 minutes, but requires Allen wrenches to complete.
FAQ
Why is there both a backpack and a controller? Isn’t the backpack redundant since there is
already a controller?
In a typical AFM design, most of the electronics housed in the Cypher backpack would be located
in the controller. The backpack, however, moves these electronics closer to the microscope;
Cypher is able to achieve very low noise levels in part because of the proximity between some of
its electronics and the actual microscope. Keeping these low noise electronics external to the
enclosure balances noise performance with the management of the heat generated by elec-
tronics.
AFM or SPM? What is the difference?
AFM stands for Atomic Force Microscope. It scans a cantilever over a sample to generate an
image. SPM stands for Scanning Probe Microscope. It is the more general, all encompassing
term, which also includes techniques that image using non-cantilever probes such as sharp metal
needles (Scanning Tunneling Microscopy), optical fibers (NSOM) or tiny hollow glass tubes (SICM).
Since Cypher is capable of both AFM and STM, it is classified as an SPM. You may see Cypher
referred to in the context of an AFM when its AFM-like functions are being described.
Page 21 of 243 4 What is a Cypher SPM system?