X-RAY-LITHOGRAPHY FOR LESS-THAN-OR-EQUAL-TO-100 NM GROUND RULES IN COMPLEX PATTERNS

Complex patterns with 75-125 nm feature sizes exposed with x-ray litho graphy are shown. Lithographic results for 75-125 nm lines with varyin g pitch are compared to simulations of image formation and resist diss olution, showing good qualitative agreement. Exposure dose latitude, n ested-to-isolated print bias, image shortening, linewidth change with gap, and linearity of printed linewidth versus mask linewidth are quan tified for 11-22.5 mu m gaps. Critical dimension control error budgets for resist linewidth uniformity are determined for logic patterns at 75 and 100 nm ground rules. Image shortening is quantified for 75-125 nm ground rule static random access memory-like patterns, indicating h ammerheads added to line ends reduce shortening to acceptable levels f or greater than or equal to 100 nm ground rules at less than or equal to 17.5 mu m gaps. With tight gap control and tight mask linewidth con trol, 100 nm ground rule complex patterns can be printed with good lat itude using x-ray lithography. (C) 1997 American Vacuum Society.