Active CMOS-MEMS conductive probes and arrays for tunneling-based atomic-level surface imaging

This paper reports on development of AFM-like active CMOS-MEMS conductive probes and arrays. The active probes are aimed for scanning tunneling microscopy (STM) imaging and field-emission (FE) assisted nanostructure formation. Two kinds of STM tip approaches compatible with CMOS-MEMS process - Electron-Induced Beam Deposition (EBID) and Spindt tip method - are presented, and their functionality is examined. Atomic-level resolution is achieved using tips in an ultra-high vacuum (UHV) STM. The MEMS probe working in ambient STM is also demonstrated. The active probe is equipped with a transimpedance amplifier (TIA) for tip FE current measurement around a nominal value of 1 nA.