Abstract The use of metal-organic chemical vapor deposition at high temperature is investigated as a means to produce epitaxial hexagonal boron nitride (hBN) at the wafer scale. Several categories of hBN films were found to exist based upon precursor flows and deposition temperature. Low, intermediate, and high NH 3 flow regimes were found to lead to fundamentally different deposition behaviors. The low NH 3 flow regimes yielded discolored films of boron sub-nitride. The intermediate NH 3 flow regime yielded stoichiometric films that could be deposited as thick films. The high NH 3 flow regime yielded self-limited deposition with thicknesses limited to a few mono-layers. A Langmuir-Hinshelwood mechanism is proposed to explain the onset of self-limited behavior for the high NH 3 flow regime. Photoluminescence characterization determined that the intermediate and high NH 3 flow regimes could be further divided into low and high temperature behaviors with a boundary at 1500 °C. Films deposited with both high NH 3 flow and high temperature exhibited room temperature free exciton emission at 210 nm and 215.9 nm.

中文翻译：

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沉积温度和氨流量对六方氮化硼金属-有机化学气相沉积的影响

摘要 研究了在高温下使用金属有机化学气相沉积作为在晶圆级生产外延六方氮化硼 (hBN) 的一种手段。根据前体流动和沉积温度，发现存在几类 hBN 薄膜。发现低、中和高NH 3 流态导致根本不同的沉积行为。低NH 3 流态产生了变色的亚氮化硼薄膜。中间 NH 3 流态产生可沉积为厚膜的化学计量薄膜。高 NH 3 流态产生了厚度限制为几个单层的自限性沉积。提出了 Langmuir-Hinshelwood 机制来解释高 NH 3 流态的自限行为的开始。光致发光表征确定中高 NH 3 流态可以进一步分为低温和高温行为，边界为 1500 °C。用高 NH 3 流量和高温沉积的薄膜在 210 nm 和 215.9 nm 处表现出室温自由激子发射。