Hill-like polycrystalline diamond grains (HPDGs) randomly emerged on a heavy boron-doped p⁺ single-crystal diamond (SCD) film by prolonging the growth duration of the chemical vapor deposition process. The Raman spectral results confirm that a relatively higher boron concentration (∼ 1.1 10²¹ cm⁻³) is detected on the HPDG with respect to the SCD region (∼ 5.4 10²⁰ cm⁻³). It demonstrates that the Au/SCD interface can be modulated from ohmic to Schottky contact by varying the surface from hydrogen to oxygen termination. The current–voltage curve between two HPDGs is nearly linear with either oxygen or hydrogen termination, which means that the HPDGs provide a leakage path to form an ohmic contact. There are obvious rectification characteristics between oxygen-terminated HPDGs and SCD based on the difference in boron doping levels in those regions. The results reveal that the highly boron-doped HPDGs grown in SCD can be adopted as ohmic electrodes for Hall measurement and electronic devices.

通过延长化学气相沉积过程的生长持续时间，山状多晶金刚石晶粒 (HPDG) 随机出现在重硼掺杂的 p ⁺单晶金刚石 (SCD) 膜上。拉曼光谱的结果证实，相对较高的硼浓度（〜1.1 10 ²¹厘米^-3）是在检测到HPDG相对于所述SCD区域（〜5.4 10 ²⁰厘米^-3）。它表明可以通过将表面从氢终止到氧终止来将 Au/SCD 界面从欧姆接触调制为肖特基接触。两个 HPDG 之间的电流-电压曲线与氧端或氢端几乎呈线性关系，这意味着 HPDG 提供了形成欧姆接触的泄漏路径。基于这些区域硼掺杂水平的差异，氧封端HPDG和SCD之间存在明显的整流特性。结果表明，在 SCD 中生长的高硼掺杂 HPDG 可用作霍尔测量和电子设备的欧姆电极。