ABSTRACT
We demonstrate an innovative method for fabrication of high-spatial-frequency grating structures. This technique makes use of the near-field diffraction patterns from computer-generated phase holograms for lithographic fabrication of grating structures with periods that are one half that of the phase hologram mask. Linear, rectilinear, and circular gratings were fabricated with this technique. Experimental results from gratings with periods to 0.5 mum and feature sizes to ~0.2 mum are presented.
ABSTRACT
Equipment has been developed for aligning lithographic features between opposite surfaces of substrates to within 1 microm. It will work with opaque substrates and allows registration to existing features on the other surface.
ABSTRACT
The authors report a case of rotational fixation of the atlanto-axial joint in which the diagnosis was not reached by conventional radiographic techniques. The clinical impression of rotational fixation was ultimately confirmed by computerized tomography. This new diagnostic modality can be very helpful in arriving at a very difficult diagnosis.
