高电流密度金刚石肖特基势垒二极管研究

Vertical diamond Schottky barrier diodes with high forward current density and large reverse breakdown electric field have been reported. A 275 nm low boron doped p^- diamond drift layer was grown on the high boron doped p⁺ single crystal diamond substrate by microwave plasma chemical vapor deposition (MPCVD). The devices were realized by fabricating ohmic and Schottky electrodes on the back side and front side of the substrate, respectively. The specific ohmic contact resistance is as low as 1.73×10^-5 Ω•cm². The ideal factor of the Schottky contact is 1.87 and the barrier height is 1.08 eV. At forward voltage of -10 V, the device shows a high current density of 22 000 A/cm², a low specific on-resistance of 0.45 mΩ•cm² and a high rectification ratio of 1×10¹⁰. The reverse breakdown voltage of the device is measured to be 110 V, resulting in a high breakdown electric field of 4 MV/cm.