It really depends on the material platform that you are interested in. In glass based platforms direct-laser writing or similar processes can be used, for crystalline semiconductors a layered deposition/growth or lithography followed by etching are the main processes.
The easiest process is an alternative deposition of films with high and low-refractive index starting and ending with the high-refractive index film. The thickness of the films is lambda/4n, where lambda is the operating wavelength and n is the refractive index of films (the well known Bragg stack), However, in order complete photonic band to open up two conditions should be satisfied:: (1) the optical contrast (difference in refractive indices of both materials) has to be higher than 0.75], and (2) the value of high refractive index material to be greater than 2.264. Here are two examples from our studies:
https://www.researchgate.net/publication/255819613_Multilayer_As2Se3GeS2_quarter_wave_structures_for_photonic_applications
https://www.researchgate.net/publication/233778462_One_Dimensional_Photonic_Crystals_comprising_organic_and_inorganic_polymers
Article Multilayer As2Se3/GeS2 quarter wave structures for photonic ...
Article One Dimensional Photonic Crystals comprising organic and ino...
Agree with S. Schulz: it depends what materials you are going to use as well as in which spectral range your PC is going to operate (you would like to use most probably transperent materials in order to build a performing 1D PC). I do not htink there is a common manufacturing platform/approach. For example, porous silicon in many cases has proved to be an excellent platform for realizing 1D photonic crystals composed by >100 lambda/4-thick layers at NIR wavelengths. For more info you can checkout my publications between 2002-2007.
Depending on the frequency region of interest, the process of of making 1D varies. In the microwave frequency region, they are simply slabs of few mm thick arranged on the air background with a gap of few mm. Once again, the thickness and gap (denoted as filling fraction: material thick/ unit cell size) depend on (a) dielectric or impedance contrast between materials forming 1 unit cell (slab-air: forms one unit cell), (b) frequency of interest. In optical region, few unit cells are sufficient to have a good 1D crystal (but requires good contrast). In the microwave frequency region, even with dielectric constant of 2, one can reasonable band gap by increasing the number of unit cells. Increase in the number of unit cells, increases sharpness and depth of the gap. It is similar to 'regular' crystals. Practical demostration will nicely show the similarity between the 'bandgap' in crystals and bandgap in photonic crystals.
"The desired process must be easy to set up and economical" - Dr. Zoubir, for a broad range of sizes, materials and low cost, ease of operation, it is hard, IMO, to beat co-extruded polymers...check out the NSF Science and Technologe Center called "Center for Layered Polymer Systems" (CLiPS) at http://www.stc-clips.org/
Peace, -mike C.
Agree with Siri Kiran Reddy that spin coating is very easy method but can not agree that it is applicable only for polymers. Spin coating is common method for obtaining metal oxides by the sol-gel method. However commonly spin coated films are less dense as compared to vacuum evaporated or sputtered but for some applications (sensors for example) this is favorable.
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