Linewidth and Writing Resolution

This chapter introduces the concept of linewidth and writing resolution in direct laser writing (DLW) lithography. The experimental factors controlling these two parameters are mainly the wavelength of the laser, the numerical aperture of the objective lenses, and the mechanical strength of the photoresist. The two-beam approach (excitation and inhibition beams) is currently the unique alternative to confine the polymerization reaction in a continuously smaller size due to the diverse advances in the knowledge of the mechanisms of depletion. The smallest feature fabricated with the two-beam approach has 9 nm linewidth and 52 nm lateral writing resolution. Thus, the DLW lithography is a promising candidate to overcome the current limitations of the manufacturing techniques providing the ability to fabricate real nanometer and closely adjacent features.