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Researchers have designed and developed many artificial patterns and shapes of materials in different sizes for RF and EO applications and designated as metamaterials. We have grown cubic, hexagonal, octagonal and pyramidal structures of commercially important infrared materials such as PbSe and its alloys which change to nanocubes at high temperature. We report the growth, nanomorphology and electrical characteristics of hyperstructured PbSe on Si substrates. Hyperbranched PbSe networks are synthesized by low temperature physical vaour transport method. The formation of branches and facets were produced in diffusion growth region. This was supported by facets formations. When PbSe and PbS-CdS were grown at 400 C without catalyst shapes stabilized into cubic morphology and nanocubes were observed significantly. X-ray showed strong growth in (001) and (111) orientations for facets. A similar study was performed for doped lead sulfide. Pure PbS showed oriented hexagonal rods which had strong directionality. PbS doped with CdS produced small rods (nanowires) randomly oriented. All these structures ultimately changed into cubes similar to that of PbS system The resistivity was very much dependent on the processing conditions. Annealing in atmosphere increased the values orders of magnitude higher. We observed significant changes in morphology after oxidation process. The level of the oxidation processes and filling of selenium vacancies with oxygen may be the reason for resistivity to increase from the range of 60KΩ to 5-10 MΩ. Also the stability of oxidized lead selenide can be explained on the basis of selenium vacancies filled by oxygen. In the past two decades, very large numbers of papers have been published on the theoretical and experimental studies of structures called meta-materials. The careful observations indicate that these structures existed since millions of years in nature in stones such as topaz and designers used in decorating glass, ceramics and wood windows and doors of palaces and churches. Also, by designing and cutting. quartz crystals handy crafted assemblies show reflections from the many surfaces and scatter even visible light in every direction, resulting in white sand that is no longer possible to see through. Based on this type of concept it has been suggested that by controlling the size and shape and arranging in an orderly fashion it is possible to use them to design different properties which can be very beneficial for devices. Lead chalcogenides are unique materials and excellent materials for high operating temperature (HOT) mid infrared wavelength (MWIR) and long infrared wavelength (LWIR) detectors. Since the early experiment of Miller, Metz and Mazelsky (1) using encapsulated pulling method to grow crystals variety of techniques have been used to produce materials with uniform and consistent properties. Solution growth, vapor growth [2], liquid phase epitaxy and travelling solvent [3] methods have produced good quality materials. Until few years back all these efforts were focused on IR detectors. However, some morphologies including nanostructures of lead selenidehas great promise for the thermoelectric cooling and power generating devices [4-6]. Nanoparticles can potentially improve the thermoelectric properties over bulk by increasing the Seebeck coefficient due to the altered electronic density of doped states or making use of a compositionally modulated material that would block phonons while transmitting electrons. Also, Quantum confinement of charge carriers in lead chalcogenides has potential to be much stronger than in most II-VI and III-V

Hyperstructure and Meta Morphology Formation in Heavy Metal Chalcogenides