ELECTRICAL LINEWIDTH TEST STRUCTURES FABRICATED IN MONOCRYSTALLINE FILMS FOR REFERENCE-MATERIAL APPLICATIONS

The physical widths of reference features incorporated into electrical linewidth test structures patterned in films of monocrystalline silic on have been determined from Kelvin voltage measurements. The films in which the test structures are patterned are electrically insulated fr om the bulk-silicon substrate by a layer of silicon dioxide provided b y SIMOX (Separation by the IR IMplantation of OXygen) processing. The motivation is to facilitate the development of linewidth reference mat erials for critical-dimension (CD) metrology-instrument calibration. T he selection of the (110) orientation of the starting silicon and the orientation of the structures' features relative to the crystal lattic e enable a lattice-plane-selective etch to generate reference-feature proper ties of rectangular cross section and atomically planar sidewal ls. These properties are highly desirable for CD applications in which feature widths are certified with nanometer-level uncertainty for use by a diverse range of CD instruments. End applications include the de velopment and calibration of new generations of CD instruments directe d at controlling processes for manufacturing devices having sub-quarte r-micrometer features.