2.3.3.3.202. NXstage_lab¶
Status:
base class, extends NXcomponent
Description:
Base class for a stage (lab) used to hold, orient, and prepare a specimen. ...
Base class for a stage (lab) used to hold, orient, and prepare a specimen.
Modern stages are multi-functional devices. Stages provide a controlled environment around the specimen. Stages enable experimentalists to apply controlled external stimuli on the specimen. A stage_lab is a multi-purpose /-functional tool that is constructed from multiple actuators, sensors, and other components.
With such stages comes the need for storing various (meta)data that are generated while working and modifying the sample.
Modern stages realize a hierarchy of components. Two examples are given to help clarify how NXstage_lab instances should be used: Take a specimen that is mounted on a multi-axial tilt rotation holder. This holder is fixed in the support unit which connects the holder to the rest of the instrument. Evidently different components are all considerable as to represent instances of stages.
In another example, taken from atom probe microscopy, researchers may work with wire samples which are clipped into a larger fixing unit to enable careful specimen handling. Alternatively, a microtip is a silicon post upon which e.g. an atom probe specimen is mounted. Multiple microtips are grouped into a microtip array to conveniently enable loading of multiple specimens into the instrument with fewer operations. That microtip array is fixed on a holder. Fixture units in atom probe are known as stubs. Stubs in turn are positioned onto pucks. Pucks are then loaded onto carousels. A carousel is a carrier unit with which eventually entire sets of specimens can be moved in between parts of the microscope. All of these units can be considered stage_lab instances.
The NXstage_lab base class reflects this hierarchy. To cover for an as flexible design of complex stages as possible, users should nest multiple instances of NXstage_lab according to their needs to reflect the differences between what they consider as the holder and what they consider is the stage. The alias field can be used to specify the community jargon if necessary.
However, a much clearer approach to reflect the hierarchy of all NXstage_lab instances is postfix each instance named stage_lab with integers starting from 1 as the top level unit. In the microtip example one could thus use stage_lab1 for the microtip, stage_lab2 for the microtip array, stage_lab3 holder, etc. The depends_on keyword should be used to additional clarify the hierarchy especially when users decide to not follow the above-mentioned postfixing notation or when is not obvious from the postfixes which stage_lab is at which level of the stage_lab hierarchy.
Some examples for stage_labs in applications:
A nanoparticle on a copper grid. The copper grid is the holder. The grid itself is fixed to a stage.
An atom probe specimen fixed in a stub. In this case the stub can be considered the holder, while the cryostat temperature control unit is a component of the stage.
Samples with arrays of specimens, like a microtip on a microtip array is an example of an at least three-layer hierarchy commonly employed for efficient sequential processing of atom probe experiments.
With one entry of an application definition only one microtip should be described. Therefore, the microtip is the specimen, the array is the holder and the remaining mounting unit that is attached to the cryo-controller is the stage.
For in-situ experiments with e.g. chips with read-out electronics as actuators, the chips are again placed in a larger unit. A typical example are in-situ experiments using e.g. the tools of Protochips.
Other examples are (quasi) in-situ experiments where experimentalists anneal or deform the specimen via e.g. in-situ tensile testing machines which are mounted on the specimen holder.
For specific details and inspiration about stages in electron microscopes:
Stages in transmission electron microscopy (page 103, table 4.2)
Further stages in transmission electron microscopy (page 124ff)
Specimens in atom probe (page 47ff)
We are looking forward to suggestions from the scientists.
Symbols:
No symbol table
- Groups cited:
Structure:
design: (optional) NX_CHAR
Principal design of the stage. ...
Principal design of the stage.
Exemplar terms could be side_entry, top_entry, single_tilt, quick_change, multiple_specimen, bulk_specimen, double_tilt, tilt_rotate, heating_chip, atmosphere_chip, electrical_biasing_chip, liquid_cell_chip
alias: (optional) NX_CHAR
Free-text field to give a term how that a stage_lab at this level of the ...
Free-text field to give a term how that a stage_lab at this level of the stage_lab hierarchy is commonly referred to. Examples could be stub, puck, carousel, microtip, clip, holder, etc.
tilt_1: (optional) NX_NUMBER {units=NX_ANGLE}
The interpretation of this tilt should be specialized ...
The interpretation of this tilt should be specialized and thus detailed via the application definition.
tilt_2: (optional) NX_NUMBER {units=NX_ANGLE}
The interpretation of this tilt should be specialized ...
The interpretation of this tilt should be specialized and thus detailed via the application definition.
rotation: (optional) NX_NUMBER {units=NX_ANGLE}
The interpretation of this rotation should be specialized ...
The interpretation of this rotation should be specialized and thus detailed via the application definition.
position: (optional) NX_NUMBER (Rank: 1, Dimensions: [3]) {units=NX_LENGTH}
The interpretation of this position should be specialized ...
The interpretation of this position should be specialized and thus detailed via the application definition.
bias_voltage: (optional) NX_NUMBER {units=NX_VOLTAGE}
Voltage applied to the stage to decelerate electrons.
POSITIONER: (optional) NXpositioner
SENSOR: (optional) NXsensor
Hypertext Anchors¶
List of hypertext anchors for all groups, fields, attributes, and links defined in this class.
