GaAs microdisk formation by mechanical scanning probe lithography

The present study investigates the features of formation of a lithographic pattern on a (100) GaAs substrate by mechanical scanning probe lithography using single-crystal diamond probes. It has been demonstrated that when the probe is pressed onto the surface and subsequently moves relative to the substrate, trenches are formed in the substrate. The depth and width of these trenches are found to be depending on the direction of movement and the shape of the probe tip. It is demonstrated that the greatest depth is achieved when the probe moves in the direction perpendicular to the plane of the edge of the tip with the largest area. Consequently, when the probe moves in a circular manner, the formed nanotrenches exhibit azimuthal inhomogeneity in their depth. This can be mitigated by tilting the substrate plane.