Research On Rectifying Characteristics Of Cubic Boron Nitride Single Crystal Based Space-charge-limited Current Effect And Schottky-contact

The single crystal material，Cubic boron nitride (c-BN)，is a syntheticcrystals. c-BN has many features, such as high hardness, a wide band gap, ahigh thermal conductivity and stable chemical properties. According to thisspecial features, this material is suitable for industrial materials and in-depthstudy. In recent years, with the constant improvement of the bulk crystal growthprocess, c-BN is recognized as excellent material to prepared the hightemperature and UV electrical devices. Therefore, this article focuses on theresearch of production progress of c-BN Schottky diode. The contactcharacteristics between a variety of metal and cubic boron nitride (c-BN), basedon this studied,the and the c-BN device which has rectifying characteristics hasbeen designed.In this paper, thick Cu probe/c-BN, fine Cu probe/c-BN, Ag probe/c-BNmechanical contact and Ag/c-BN metallurgical contacts studied experimentally.The results showed that Ag/c-BN metallurgical junction having an ohmiccontact characteristics, fine Cu Probe/c-BN in contact with the Schottky barriermetal contact characteristics of the probe and the three best performance. Theundoped and doped Si, c-BN rectifier, the threshold voltage of4.6V and4V; at-24V and23.5V, the reverse current is less than10-6A, i.e. in an off state; at10V,the undoped the sample after the sample and spread rectification ratio of123 and376.The results of c-BN IV characteristics of the device have to forward currentand voltage exhibits quadratic function, while the conventional diode IVcharacteristics in the forward should be an exponential relationship. Therefore,this paper established a theory of space charge limited current (SCLC) deviceacts as a major role model, and proposed an equivalent circuit diagram of thesample device.This article have been carrying out the temperature characteristics of therectifier and switching characteristics of the test work. Which, in the temperaturetest rectifier can operate at500K or more, by a5V voltage Current-Temperature dependency graph shows that the trap center thermal activationenergy△E is0.31eV. In the switching characteristics experiments, eachdevice can be observed response function and signal wave peak to peak arelinked, and the use of theoretical models for the corresponding data SCLCcarried out a detailed analysis of finishing. In the follow-up to the temperaturecharacteristics of the device test, we can see the device at700K after diffusiontemperatures can still work and showed rectifying characteristics.Finally, this paper summarized research work carried out and made furtherresearch prospects.