The structural stability of heat-treated CoN/CN soft X-ray multilayers fabricated by dual-facing-target sputtering has been investigated by using complementary measurement techniques.The high temperature annealing res...The structural stability of heat-treated CoN/CN soft X-ray multilayers fabricated by dual-facing-target sputtering has been investigated by using complementary measurement techniques.The high temperature annealing results imply that the destructive threshold of the Co/C multilayers is improved by 100-200 degrees centigrade through doping with N.The low-angle X-ray diffraction of CoN/CN soft X-ray multilayers indicates that the period expansion of the multilayers is only 4 % at 400℃,and the interface pattern still exists even if they were annealed at 700℃.The Raman spectra analyses give the evidence that the formation of the sp bonding in the CN sublayers can be suppressed effectively by doping N with atoms,and thus the period expansion resulting from the changes in the density of CN layers can be decreased considerably.The X-ray photoelectron spectra analyses present the information of the existence of the strong covalent bonding between C and N atoms,and the ionic bonding between Co and N atoms,which can slow down the tendency of the structural relaxation.The interstitial N atoms decrease the mobility of Co atoms,and thus the fee-Co and hep-Co coexist even though the annealing temperature is much higher than the phase transformation temperature of 420℃,leading to the suppression of the grain growth.展开更多
The structures of the carbon sublayers in the annealed Co/C soft X-ray multilayers fabricated by using a dual-facing-target sputtering system have been characterized by transmission electron microscopy (TEM) and Raman...The structures of the carbon sublayers in the annealed Co/C soft X-ray multilayers fabricated by using a dual-facing-target sputtering system have been characterized by transmission electron microscopy (TEM) and Raman spectroscopy (RS). The results suggest that the structural variations in the carbon layers can be roughly divided into three stages, i e ordering, crystalline and grain growth stages. At the ordering stage with annealing temperatures below 400℃, the amorphous carbon layers change from ones of bond-angle disorder and fourfold-bonding only to ones of threefold-bonding. At the crystalline stage, the amorphous carbon layers in the as-deposited multilayers crystallize to graphite crystallites in the annealing temperature range of 500-600℃ At the grain growth stage, the specimens are annealed at temperatures higher than 700℃ A growth in the graphite crystallite dimensions is observed, which is consistent with the TEM results展开更多
基金Project supported by the National Natural Science Foundation of China and Beijing Zhongguancun Associated Center of Analysis and Measurement.
文摘The structural stability of heat-treated CoN/CN soft X-ray multilayers fabricated by dual-facing-target sputtering has been investigated by using complementary measurement techniques.The high temperature annealing results imply that the destructive threshold of the Co/C multilayers is improved by 100-200 degrees centigrade through doping with N.The low-angle X-ray diffraction of CoN/CN soft X-ray multilayers indicates that the period expansion of the multilayers is only 4 % at 400℃,and the interface pattern still exists even if they were annealed at 700℃.The Raman spectra analyses give the evidence that the formation of the sp bonding in the CN sublayers can be suppressed effectively by doping N with atoms,and thus the period expansion resulting from the changes in the density of CN layers can be decreased considerably.The X-ray photoelectron spectra analyses present the information of the existence of the strong covalent bonding between C and N atoms,and the ionic bonding between Co and N atoms,which can slow down the tendency of the structural relaxation.The interstitial N atoms decrease the mobility of Co atoms,and thus the fee-Co and hep-Co coexist even though the annealing temperature is much higher than the phase transformation temperature of 420℃,leading to the suppression of the grain growth.
基金Project supporied by the National Natural Science Foundation of China and Beijing Zhongguancun Associated Center of Analysis and Measurement
文摘The structures of the carbon sublayers in the annealed Co/C soft X-ray multilayers fabricated by using a dual-facing-target sputtering system have been characterized by transmission electron microscopy (TEM) and Raman spectroscopy (RS). The results suggest that the structural variations in the carbon layers can be roughly divided into three stages, i e ordering, crystalline and grain growth stages. At the ordering stage with annealing temperatures below 400℃, the amorphous carbon layers change from ones of bond-angle disorder and fourfold-bonding only to ones of threefold-bonding. At the crystalline stage, the amorphous carbon layers in the as-deposited multilayers crystallize to graphite crystallites in the annealing temperature range of 500-600℃ At the grain growth stage, the specimens are annealed at temperatures higher than 700℃ A growth in the graphite crystallite dimensions is observed, which is consistent with the TEM results
