Development of a Low Cost Nanoscale Stylus Probe Based on a DVD Pick-Up Head

摘要

This study develops a low-cost nanoscale probe for surface profiling applications featuring a diamond stylus mounted on a highly-rigid suspension system and an optical displacement sensor based upon a modified commercial DVD pick-up head. Through an appropriate design of the suspension system and the use of a clamping arrangement comprising a roller and two spherical ball-bearings, the displacement of the probe as it traces over the surface of interest is restricted to the vertical direction only. It is shown experimentally that the probe has a measurement range of 5.4 urn, a linear displacement measurement error of 53.1nm, and a linearity error of 0.9%. The feasibility of the probe for practical surface profiling applications is confirmed by constructing a 3-D surface topography mapping system comprising the nanoscale probe, a commercial piezo ceramic linear motor (PCLM) positioning stage and a proprietary software control system constructed in the Borland C++ Builder environment. The experimental results demonstrate the ability of the proposed system to obtain highly accurate profile measurements of objects with either a very large radius of curvature or significant surface gradients.