In this paper, techniques developed in the fabrication of nano-structures such as photonic gratings and vertical tube structures are presented for fabrication development that is applicable in the field of MEMS/NEMS technology – particularly for the optical integrated circuits  and sensor devices . In such applications, not only is the resolution enhancements important, it is also often imperative that Critical Dimensions Uniformity (CDU) be kept as low as possible - since device performance often times scales directly with structural dimensions and its accuracy . In this regard, techniques such as phase shift masking, off-axis illumination, optical proximity corrections, and also multiple patterning and resist ashing etc needs to be employed. This, not only increases the number and complexity of processing steps; it (at the same time) implicates other specifications such as illumination apertures, mask designs, optical proximity simulations, tool overlay tolerances etc. Coupled with additional non-CMOS requirements of atypical pattern shapes and densities, such as rings, horse-shoe shapes, sharp edges etc, a comprehensive study of the flexibilities involved with micro-lithography needs to be carried out for novel design prototyping. Here, the above described are illustrated, using examples of (i) a photonic gratings structure patterned with sharp edges, and (ii) a vertical-tube switch device structure, which are presented and discussed for their fabrication techniques and measurement results.