Electrical Vernier Alignment Measurement
Original Publication Date: 1983-Sep-01
Included in the Prior Art Database: 2005-Feb-07
An electrical vernier alignment measurement system for measuring the alignment of two metal layers, i.e., two levels of metallurgy, is shown in the drawing. Conductor #2 is the upper level, and conductors #1 and #3 are the lower level. A misalignment would shift conductor #2 left or right (Wx). Conductor #1 is the measurement, and conductor #3 serves as a reference. Conductors #1 and #3 are equivalent such that the resistance of one zig-zag (one period) of conductor #1 may be calculated by measuring conductor #3 and dividing its resistance by the number of periods. In a perfectly aligned system, conductor #2 would short out conductor #1 from the slider to Tab #0. Thus, the resistance of conductor #1 would be reduced by 5 periods.