The Defects Recovery Study Of Neutron Irradiated 6H-SiC

As the third generation of semiconductor materials,SiC makes up for the defects of the traditional semiconductor devices such as Si and GaAs,which can not meet the requirements of modern electronic technology for high temperature,high frequency,high pressure and radiation hardness.The application of SiC electronic devices in aerospace,chemical,communications,energy and space science is very promising.,especially in nuclear energy.It is widely used in nuclear energy technology and is a backup material for nuclear fission and fusion reactors.The research object of this paper is the 6H-SiC single crystal irradiated by high dose neutron,which has a total of 2.85×1020 n/cm2.The 6H-SiC is annealed from 200? to 1700 C,so that the defects produced by neutron irradiation can be recovered.In this paper,X ray diffraction(XRD)is used as a basic measurement method to study the defect mechanism of 6H-SiC single crystal irradiated by neutron and its annealing recovery stage by using the diffraction peak of 6H-SiC single crystal(0001)plane.In this paper,study results obtained are as follow:1.it is found that the full width at half maximum dramatic decline at 200? to 600 ?,and it is no obviously change at 600 ?-1400 ?,but the value falls again until the pre irradiation value when the temperature is higher than 1400 ?.2.Meanwhile,the interplanar distance decreases continuously from 200? to 1400 ?,then increases with the increase of annealing temperature,and finally approaches the pre-irradiation value.3.It is believed that a large number of point defects and line defect are produced within the sample by neutron irradiation.,and most of these defects can be eliminated by high temperature annealing.In the process of XRD testing,the surface of wafer is not on the same plane as the crystal plane,which has a great influence on the XRD test.In this case,a directional detection method is used to make the sample only use X ray powder diffraction without without the isotropic requirement in macro scale to the sample,which obtain.accurate data information.