Image Number 2 for United States Patent #6451135.
There is provided copper targets for sputtering capable of forming a deposition film with low electric resistance indispensable for high-speed operation elements and also with excellent thickness uniformity, and such thin copper films. A high-purity copper sputtering target is characterized by comprising up to 0.1 ppm each Na and K, up to 1 ppm each Fe, Ni, Cr, Al, Ca, Mg, up to 5 ppm each carbon and oxygen, up to 1 ppb each U and Th, and, excluding gaseous constituents, more than 99.999% copper. Preferably the average grain size on the sputter surface is 250 .mu.m or below, with its dispersion thin plus or minus 20%. I(111)/I(200) of X-ray diffraction peak intensity on the sputter plane is at least 2.4 with its dispersion within plus or minus 20%.
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