Patent ID: 6977986

Claim:
A method of aligning a substrate in an apparatus, characterised in that the apparatus incorporates a lithographic tool for printing a pattern onto the substrate and a diffractive substrate angle measuring tool for measuring angular orientation of one or more crystal planes of the substrate, the method comprising: (a) calibrating angular orientation of the pattern relative to the measuring tool; (b) inserting the substrate into the lithographic tool; and (c) measuring angular orientation of said one or more crystal planes of the substrate using the measuring tool, and rotating the substrate until its one or more crystal planes angularly align to the pattern; the pattern thereby angularly aligned to the substrate and to said one or more crystal planes thereof, wherein the measuring tool operates at X-ray radiation wavelengths and measures diffracted X-ray radiation resulting from Bragg diffraction within the substrate, the correct angular orientation of said one or more crystal planes being determined by an X-ray count rate in an X-ray detector of said measuring tool.