Oxford Instruments Cypher SPM, Руководство пользователя

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Cypher SPM
User Guide
1. Measure the Sample Bias voltage on the scanner's terminal block.
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Check the 'Use' check box next to the Sample Voltage
parameter in the DoIV control panel.
Note: In this example, the measured offset Bias
voltage is -46 mV.
2. Enter the amount of offset voltage needed in the S. Voltage Offset control parameter.
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Use the opposite sign of the voltage measured on your
voltmeter to negate the actual voltage.
Note: Make sure that the Sample voltage parameter is
set to 0 volts when making this adjustment.
3. Change the Sample voltage parameter and verify that the corresponding voltage appears on
the Sample pin on the scanner's terminal block.
27.2 Preparing the sample
Sample preparation varies but basically the goal is to provide an electrical path between the sample
bias and the surface of your sample. In addition to the electrical connection, care should be taken
to mount the sample mechanically to a sample puck as you would with any sample.
The ORCA kit comes with a practice sample of graphite (HOPG) mounted to a steel puck. A small
magnet is attached to the sample puck to provide an easy way for the bias lead to attach.
The magnetic connection method is convenient but is not necessary. A bias lead of your own
design can be mounted directly to the sample puck and used as long as the end of the lead is able
to fit into the sample voltage socket on the scanner's terminal block. Also, be certain to use wire
that is flexible enough not to impede normal scanning.
The following steps describe how this sample was prepared.
1. Use a small amount of 5 minute epoxy to attach the HOPG to the sample puck.
2. Place a magnet onto the puck.
3. Cover the sides of the sample and the entire magnet with silver paint.
Note: The silver paint is not an adhesive. It will not provide good attachment of the sample
to the sample puck. Use the paint only to make an electrical connection from the sample to
the bias voltage lead.
27 Preparing for conductive AFM imaging on the standard scanner Page 191 of 243