The thick diamond films were deposited uisng DC arc plamsa jet CVD.The influence of substrates temperature on the growth and stress of the diamond films were investigated by SEM,Raman spectra and XRD.The results shown that the thick diamond films deposited at 950 ℃ exhibited excellent crystal quality and high diamond phase purity,while those grown at 850 ℃ and 1 050 ℃ were of poor crystal quality and with large amount of twin defects and non-diamond carbons.In addition,as the increase of substra...