In-situ transient current detection in local anodic oxidation nanolithography using conductive diamond-coated probes

Achieving precise control over oxidation growth has become a key bottleneck in quality control in local anodic oxidation (LAO) nanolithography due to the lack of effective process monitoring and feedback control approaches. In this context, this paper proposed and presented an in-situ current detection approach to monitor the status of oxidation growth in real-time in the LAO processes using highly durable conductive diamond-coated probes. Research findings indicate that the use of diamond-coated probes can induce controllable LAO with transient current at the microampere level and create nanostructures with heights exceeding 18 nm, which are notably superior to those obtained using doped silicon probes. It was also demonstrated that, within a certain range of voltage, the detected current could reflect the oxidation growth during the fabrication of nanolines, with the detected current correlating to the conductivity of the oxidised surface, indicating the extent of oxidation. It is expected that the combination with flexible pulse modulation will promise a flexible and simple approach to tuning oxidation growth, paving the way for the production of high-quality oxide lines.