Hi all, I need silicon wafers with the following specs: orientation: (110)+/- the best possible value flat: (111))+/- the best possible value Surfaces: DSP TTV: the lowest possible value Bow: the lowest possible value Warp: the lowest possible value Thickness: i can accept any thickness, (i can accept also 1cm or more thick material) I'm interested only to low TTV, warp, bow. I need a flatness of 500 or less over an area of 30mm x 10mm. Do you know someone able to provide such material ? Eventually, i can buy thick silicon wafers from commercial sources, and then find a company able to reprocess them. I presume that ideal whould have the job made by a company specialized in optics realizations. I also have some technical questions: which is the relation between warp, ttv, bow and flatness of a wafer ? For my understanding, TTV is not related to flatness of wafer: you can have any TTV, but very planar surfaces of silicon wafer. For my understanding, a low warp and bow values translates in high flatness, is this correct ? Many thanks, Andrea