Self-consistent proximity effect correction technique for resist exposure (SPECTRE)

Submicron electron-beam lithography for the direct exposure of wafers and for the fabrication of masks cannot be successful until the incident electron exposure can be properly adjusted to compensate the proximity effects. A self-consistent proximity effect correction technique for resist exposure (SPECTRE) has been developed to compute, for any given pattern, the corrections to the incident electron exposure which must be applied in order to obtain ’’uniform’’ absorbed (incident plus backscattered) exposure in the resist. Mathematically, the solution is unique for any given proximity function. SPECTRE has been successfully implemented on practical pattern data. Experimentally, simultaneous delineation of pattern geometries from 1/4 to 2 μm has been achieved by an automatic application of SPECTRE.