NT-MDT Solver Next - 8 Lithography; Overview; Vector Lithography

Chapter 8. Lithography
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8. Lithography
8.1. Overview
This manual is intended for a user experienced in conducting measurements with NT-MDT
instruments using contact and semicontact atomic force microscopy and spectroscopy.
The Nova P9 program provides three lithography technologies:
● Force lithography. During the lithography process, the force applied to the sample by
the sharp probe tip is maintained constant (see Chapter 8.2 on p. 168);
● Charge lithography. During the lithography process, the electrical sample-probe bias
is maintained constant (see Chapter 8.3 on p. 188);
● Current lithography. During the lithography process, the electrical sample-probe bias
is controlled to maintain the current constant (see Chapter 8.3 on p. 188).
Every of those technologies can operate either in the vector (see i. 8.1.1 on p. 163) or in the
raster mode (see i. 8.1.2 on p. 167).
8.1.1. Vector Lithography
Vector lithography is the process of influence on the sample surface during the probe
movement along the predefined vector template.
The vector lithography procedure needs a lithography area and a lithography template (a
series of lithography objects) to be defined before starting the procedure.
When the probe moves to the starting point of the first object or to the starting point of the
next object after finishing the current one, the sample is applied to the force
A0. Depending
on the technology in use, level of the A0 parameter is defined in one of the following fields
in the
Litho window:
● for force lithography – in the SetPoint field (in nA);
● for charge lithography – in the BV field (in V);
● for current lithography – in the BV_SP field (in nA).
Duration of a lithography process depends on mechanical speed of the probe movement.
This speed is defined in the Rate field of the Control panel of the Litho window.
The Nova P9 program provides four options to perform the vector lithography:
● Simple vector lithography (see i. 8.1.1.1 on p. 164);
● Gradient lithography (see i. 8.1.1.2 on p. 164);
● Pulse lithography (see. i. 8.1.1.3 on p. 165);
● Pulse-gradient lithography (see i. 8.1.1.4 on p. 166).
These options are explained in details below.