| As one new-type artificial synthesis semiconductor with large band gap , cubic boron nitride was synthesized by R.H.Wentorf by using the temperature-gradient method for the first time in 1957. cBN is one typical Ⅲ-Ⅴcompound and has zinc-blende structure.Due to several unique properties including large band gap up to 6.3eV and steady chemistry properties ,cBN is regarded as the ideal material that will be made to high-power shortwave devices which can work at high temperature. Therefore , cBN attracts much attention for its potential application to semiconductor and optical devices. It is insulated for pure cBN single crystal and we can gained p-and n-type crystals using two kinds of ways. Appropriate impurities such as Si or Be is added into the material when cBN is synthesized. Diffusing method is the other way .After cBN is synthesized under high pressure and high temperature, it becomes doped as result of impurities diffusing at high temperature and vacuum. All the properties of cBN is unique among the materials with wide band gap and that makes it possible to fabricate p-n junctions and ultraviolet-light-emitting diodes. Mishima made p-n junction when they grew n-type cBN crystals on p-type one in 1990's and enhanced the temperature to 650℃at which the I-V characteristic curve of p-n junction was kept well. Their work showed that the study on cBN semiconductor had entered into a new phase from then on. However,the fundamental study of the semiconducting properties of cBN has not largely progressed for many years, probably due to the lack of large-scale single crystals of high quality because of the synthesis technology. Technical difficulties associated with the process of obtaining p-n junction crystals under high pressure may have also prevented further investigation of the ultraviolet-light-emitting nature of cBN crystals. Recently, we have studied the semiconducting properties of cBN single crystals contained no intentional dopants and synthesized under high pressure and high temperature, and acquired some better advancement. We have investigated the thermally stimulated current curve of cBN. The method of TSC is new technology developed from medium physics. These electrons and holes which are trapped by the traps at low temperature come to emit to the conduction band or valence band along with the sample temperature's rising. The TSC curve will be made by measuring the change of the current flowing through the sample and the position and height of TSC peak depends on traps'depth and density. As a result, we can measure the microcosmic parameter of semiconductors such as the activation energy.As to cBN single crystals contained no intentional dopants, it is likely to be imported some impurities when it is synthesized .These crystal lattice defects and impurity radicles will give birth to deep levels which are possibly consecutive in forbidden band of cBN. As the recombination centers or traps ,these levels in the forbidden band have great influence on the electrics properties and optics properties of cBN because the life of non-equilibrium carries depend on them. The study on the relation between the TSC curve and defects centers of cBN and the traps's activity in cBN will make us know the new type semiconductor well and make deeper research on the compensate mechanism and electric mechanism in cBN. Non-equilibrium carries made by the electrics immitting method at low temperature which is achieved by use of liquid hydronitrogen are partially trapped by traps and then they begin to emit to the conduction band with the temperature of cBN rising .These carries out of traps will change the resistance of cBN, so we acquired the TSC curve of cBN by measuring change of the current though cBN from 73K to 320K using X-Y plot .After analyzing this curve, we found out the position of one of traps level. We placed cBN on a floor aiming at it's tiny size .We fabricated electrode and conceived one better electrode structure. We have measured the I～V dependence of cBN on the positive and...
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