Reducing The Process k Factor With Surface Imaging Techniques

The standard Rayleigh relation for the resolution of an optical system states that the resolution is proportional to the exposure wavelength divided by the numerical aperture of the system. The constant of proportionality "k" is directly effected by processing techniques and may be reduced depending on the chosen photoitsist process. Reducing the "k" factor directly impacts the manufacturing of advanced integrated circuits since it implies the ability to resolve finer features without the ever larger capital expenditures required for new exposure tools. It also allows the execution of current processes with increased processing latitude. This paper reports on the results obtained using a surface imaging technique to reduce the "k" factor for standard and advanced processing applications.