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At present, photonic technologies boost most areas of both communication and sensing. Coincidently, most applications of the novel technical solutions based on any sort of O1)tiCal elements can be found here. Beside of classic bulk optics, there is a rising importance of planar and diffractive optics which is able not only to take many typical tasks of the conventional optics over but also to open guite a few new applications. For the planar and diffractive optics is based on the structures of the size comparable to or smaller then a wavelength, it utilises a modern technology, very the same as a semiconductor microelectronics does. One of the technology noticeably used here is an electron beam lithography which allows to generate the dielectric structures with the lateral accuracy up to 0. 1 micron or even less. Inventioned originally for conductive materials the EBL brings some limitations and peculiarities to the fabrication of the dielectric structures like trapped charge effects, proximity effect and others which will be briefly discussed. Most dielectric structures produced by direct EBL are composed of ultra fine relief patterns created either onto the flat bulk waffer surface or onto the layered sandwitch substrate. The physical methods of microfabricatiou (plasma etching) allow to get the reliefs of the depth comparable to the wavelength of light.
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