Method and apparatus for operating a scanning microscope
AssigneeSiemens Aktiengesellschaft
InventorsHans-Detlef Brust, Johann Otto
Life of this patent
Estimating the term…
Abstract
A scanning microscope scans over the surface of a specimen to be tested in point-by-point fashion with a probe. The scan rate of the probe is controlled as dependent on a secondary electrical signal derived from the measuring point of the specimen surface and, thus, serves as a control signal to the output signal of a signal processing unit which is evaluated at a window discriminator or comparator. The output signal is supplied to a voltage controlled oscillator of the scan generator through an adjustable timer element. Simultaneously, the evaluated output signal is used for modulating the intensity of the write beam of a display means for controlling the intensity of the probe.
Claims9
An apparatus for scanning a specimen surface, comprising:
- a scanning microscope having a scanning primary beam;
- a scan generator for generating a scan signal to scan said primary beam;
- a specimen control connectable to a specimen to be tested;
- a signal processing arrangement connected to receive signals from the specimen to be tested;
- a threshold circuit connected to an output of said signal processing arrangement;
- a first signal line connecting an output of said threshold circuit to an input of said specimen control;
- and
- an adjustable timer element connecting an output of said threshold circuit to an input of said scan generator for switching from a first to a second lower scan rate.
A method for operating a scanning microscope having a probe generated in a probe-shaping portion and capable of being scanned over a specimen using a deflection unit, comprising the steps of:
- establishing a defined operating condition in the specimen for testing;
- scanning the probe point-by-point over regions of a specimen surface to be tested;
- converting the effects triggered by the interaction of the specimen and the probe into electrical signals;
- supplying said electrical signal to an arrangement for signal processing
- evaluating said electrical signal by said arrangement for signal processing;
- and
- controlling the intensity of said probe depending on an output signal from said arrangement for signal processing.
An apparatus for scanning a specimen surface, comprising:
- a scanning microscope having a scanning primary beam;
- a scan generator for generating a scan signal to scan said primary beam;
- a specimen control connectable to a specimen to be tested;
- a signal processing arrangement connected to receive signals from the specimen to be tested;
- a threshold circuit connected to an output of said signal processing arrangement;
- a first signal line connecting an output of said threshold circuit to an input of said specimen control;
- and
- said threshold circuit having an output connected to a control input of said scan generator for chronologically limited reversal of the scan direction and for reswitching to an original scan direction following said reversal, switching to a lower second scan rate being simultaneous with said reswitching.
An apparatus for scanning a specimen surface, comprising:
- a scanning microscope having a scanning primary beam;
- a scan generator for generating a scan signal to scan said primary beam;
- a specimen control connectable to a specimen to be tested;
- a signal processing arrangement connected to receive signals from the specimen to be tested;
- a threshold circuit connected to an output of said signal processing arrangement;
- a first signal line connecting an output of said threshold circuit to an input of said specimen control;
- display means having deflection means for a write beam connected to said scan generator;
- and
- a switchover means connectible to an input of said display means for controlling the intensity of said write beam to an output of said threshold circuit with a signal.
Dependencies are inferred from the claim text.