Lloret Fernando, Eon David, Bustarret Etienne, Fiori Alexandre, Araujo Daniel
Department of material science and ME and IQ, University of Cádiz, Puerto Real, 11510 Cádiz, Spain.
Institute for Material Research, Hasselt University, 3590 Diepenbeek, Belgium.
Nanomaterials (Basel). 2018 Jun 29;8(7):480. doi: 10.3390/nano8070480.
Epitaxial lateral growth will be required if complex diamond-based device architecture, such as, for example, Metal-oxide-semiconductor Field-effect transistors (MOSFETs) or epitaxial lateral overgrowth (ELO) substrates, need to be developed for high-power applications. To this end, undoped and doped non-planar homoepitaxial diamond were overgrown on (001)-oriented diamond-patterned substrates. Defects induced by both the heavy boron doping and three-dimensional (3D) growth were studied by transmission electron microscopy (TEM). At high methane and boron concentrations, threading dislocations with Burgers vectors = 1/6 ⟨211⟩, = 1/2 ⟨110⟩, or both were observed. Their generation mechanisms were established, revealing boron proximity effects as precursors of dislocations generated in boron-doped samples and providing clues as to the different Burgers vectors. The concentration ranges of boron and methane resulting in good crystalline quality depended on the plane of growth. The microwave plasma-enhanced chemical vapour deposition (MPCVD) growth conditions and the maximum boron concentration versus plane orientation yielding a dislocation-free diamond epitaxial layer were determined.
如果需要为高功率应用开发基于金刚石的复杂器件架构，例如金属氧化物半导体场效应晶体管（MOSFET）或外延横向过生长（ELO）衬底，就需要进行外延横向生长。为此，在（001）取向的金刚石图案化衬底上生长了未掺杂和掺杂的非平面同质外延金刚石。通过透射电子显微镜（TEM）研究了重硼掺杂和三维（3D）生长所诱导的缺陷。在高甲烷和硼浓度下，观察到伯格斯矢量为 = 1/6〈211〉、 = 1/2〈110〉或两者皆有的穿透位错。确定了它们的生成机制，揭示了硼邻近效应是硼掺杂样品中产生位错的前驱体，并为不同的伯格斯矢量提供了线索。导致良好晶体质量的硼和甲烷浓度范围取决于生长平面。确定了微波等离子体增强化学气相沉积（MPCVD）的生长条件以及产生无位错金刚石外延层的最大硼浓度与平面取向的关系。
