Akhtar Fatima, Dabrowski Jaroslaw, Lukose Rasuole, Wenger Christian, Lukosius Mindaugas
IHP - Leibniz-Institut für innovative Mikroelektronik, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany.
BTU Cottbus Senftenberg, Platz der Deutschen Einheit 1, 03046 Cottbus, Germany.
ACS Appl Mater Interfaces. 2023 Aug 2;15(30):36966-36974. doi: 10.1021/acsami.3c05860. Epub 2023 Jul 21.
For the fabrication of modern graphene devices, uniform growth of high-quality monolayer graphene on wafer scale is important. This work reports on the growth of large-scale graphene on semiconducting 8 inch Ge(110)/Si wafers by chemical vapor deposition and a DFT analysis of the growth process. Good graphene quality is indicated by the small FWHM (32 cm) of the Raman 2D band, low intensity ratio of the Raman D and G bands (0.06), and homogeneous SEM images and is confirmed by Hall measurements: high mobility (2700 cm/Vs) and low sheet resistance (800 Ω/sq). In contrast to Ge(001), Ge(110) does not undergo faceting during the growth. We argue that Ge(001) roughens as a result of vacancy accumulation at pinned steps, easy motion of bonded graphene edges across (107) facets, and low energy cost to expand Ge area by surface vicinals, but on Ge(110), these mechanisms do not work due to different surface geometries and complex reconstruction.
对于现代石墨烯器件的制造而言，在晶圆尺度上实现高质量单层石墨烯的均匀生长至关重要。本文报道了通过化学气相沉积在半导体8英寸Ge(110)/Si晶圆上大规模生长石墨烯以及对生长过程的密度泛函理论（DFT）分析。拉曼2D峰的半高宽较小（32 cm）、拉曼D峰与G峰的强度比低（0.06）、扫描电子显微镜（SEM）图像均匀，这些都表明石墨烯质量良好，霍尔测量也证实了这一点：迁移率高（2700 cm²/V·s）且薄层电阻低（800 Ω/sq）。与Ge(001)不同，Ge(110)在生长过程中不会出现刻面。我们认为，Ge(001)之所以变得粗糙，是由于固定台阶处空位的积累、键合的石墨烯边缘在(107)晶面上的容易移动以及通过表面相邻原子扩展Ge面积的能量成本较低，但在Ge(110)上，由于不同的表面几何形状和复杂的重构，这些机制不起作用。
