传输线模型测量Au/Ti/p型金刚石薄膜的欧姆接触电阻率

采用传输线模型测量了重B掺杂p型金刚石薄膜(约10²⁰cm^-3)上Ti/A u欧姆接触电阻率ρ_c，测试了500℃退火前后及大电流情况下的I-V特性，研究 了退火对ρ_c的影响.结果表明，重掺杂和退火工艺是改善欧姆接触的有效手段. ρ_c随测试温度的变化表明金属/半导体接触界面载流子输运机制为隧道穿透.而 光照对ρ_c影响的分析表明金刚石可作为理想窗口材料.测试得到的最低ρ _c值约为10^-4Ωcm². 关键词： 金刚石薄膜 欧姆接触 接触电阻率

MEASUREMENT OF THE SPECIFIC CONTACT RESISTANCE OF Au/Ti/p-DIAMOND USING TRANSMIS SION LINE MODEL

The measurements of the specific contact resistance (ρ_c) were carrie d out for Ti/Au ohmic contact to heavily boron-doped p-diamond (～10²⁰cm^-3) by the transmission line model (TLM).I-V measurements were per formed before and after annealing at 500℃,as well as in big current cases.The a nnealing effects on the ρ_c value were investigated.It is shown that heavy doping of the semiconductor and annealing are effective means to improve o hmic contacts.The changes of ρ_c value with the operating temperature are discussed.We suggest that the dominant transport mechanism at the metal/sem iconductor interface is tunneling.No light effects on the ρ_c value h ave been observed,the results show that diamond can be an ideal window material. In our experiments,the smallest ρ_c value of the Au/Ti/p-diamond reac hes ～10^-4Ωcm².