SCANNING TUNNELING MICROSCOPY - CRITICAL DIMENSION AND SURFACE-ROUGHNESS ANALYSIS

Applications of a scanning tunneling microscope combined with an optical microscope for metrology are reported. The ability to perform critical linewidth measurements on device structures is demonstrated. The need for such a high-resolution metrology tool is illustrated by comparing scanning electron microscope and scanning tunneling microscope images of metal contacts for quantum devices which were fabricated by e-beam lithography and metal lift-off. These contacts are typically 100 nm in diameter and vary between 30 and 100 nm in height. Another topic being addressed is the effectiveness of annealing and electropolishing on the topography of stainless-steel tubing interior surfaces. This study was initiated to reduce particle entrapment in liquid and gas supply lines being designed for our new fabrication facilities at Texas Instruments.