Publications

This paper describes the fabrication and measurement of the linewidths of the reference segments of cross-bridge resistors patterned in (100) Bonded and Etched Back Silicon-on-Insulator (BESOI) material. The critical dimensions (CD) of the reference segments of a selection of the cross-bridge resistor test structures were measured both electrically and by Scanning-Electron Microscopy (SEM) cross-section imaging. The reference-segment features were aligned with <110> directions in the BESOI surface material and had drawn linewidths ranging from 0.35 to 3.0 {micro}m. They were defined by a silicon micro-machining process which results in their sidewalls being atomically-planar and smooth and inclined at 54.737{degree} to the surface (100) plane of the substrate. This (100) implementation may usefully complement the attributes of the previously-reported vertical-sidewall one for selected reference-material applications. For example, the non-orthogonal intersection of the sidewalls and top-surface planes of the reference-segment features may alleviate difficulties encountered with atomic-force microscope measurements. In such applications it has been reported that it may be difficult to maintain probe-tip control at the sharp 90{degree} outside corner of the sidewalls and the upper surface. A second application is refining to-down image-processing algorithms and checking instrument performance. Novel aspects of the (100) SOI implementation that are reported here include the cross-bridge resistor test-structure architecture and details of its fabrication. The long-term goal is to develop a technique for the determination of the absolute dimensions of the trapezoidal cross-sections of the cross-bridge resistors' reference segments, as a prelude to developing them for dimensional reference applications. This is believed to be the first report of electrical CD measurements made on test structures of the cross-bridge resistor type that have been patterned in (100) SOI material. The electrical CD results are compared with cross-section SEM measurements made on the same features.