FORCE MICROSCOPY IMAGING OF PHOTOPATTERNED ORGANOSILANE MONOLAYERS - APPLICATION TO PROBE ALIGNMENT IN AFM PATTERNING FOLLOWING PHOTOLITHOGRAPHY

Photomask patterns were transferred to a self-assembled organosilane m onolayer by vacuum ultraviolet irradiation through the photochemical d egradation of the monolayer in the irradiated area. The monolayer was thus demonstrated to serve as a photoresist. The photofabricated patte rns on the monolayer resists were observed by atomic force microscopy (AFM) in various imaging modes. Without developing the exposed monolay er resist, the patterns that is, the latent images - were clearly imag ed by lateral force microscopy in contact AFM mode or phase contrast i maging in intermittent contact AFM mode, based on the differences in c hemical properties between the degraded and undegraded monolayer regio ns. The photodegraded region showed stronger adhesive force than the u nirradiated region. In addition, the latent image on the monolayer res ist could be imaged by force modulation microscopy because of the diff erences in mechanical properties between the photoirradiated and unirr adiated monolayer regions. Using such force microscopy images, an AFM probe was accurately aligned to a specific location on the photoprinte d pattern in order to draw an additional pattern by AFM lithography.