Vangala Shivashankar, Siegel Gene, Prusnick Timothy, Snure Michael
Air Force Research Laboratory, Sensors Directorate, Wright Patterson AFB, 45433, USA.
KBR Wyle Laboratories, Beavercreek, OH, 45433, USA.
Sci Rep. 2018 Jun 11;8(1):8842. doi: 10.1038/s41598-018-27237-z.
Wafer scale (2") BN grown by metal organic chemical vapor deposition (MOCVD) on sapphire was examined as a weakly interacting dielectric substrate for graphene, demonstrating improved transport properties over conventional sapphire and SiO/Si substrates. Chemical vapor deposition grown graphene was transferred to BN/sapphire substrates for evaluation of more than 30 samples using Raman and Hall effects measurements. A more than 2x increase in Hall mobility and 10x reduction in sheet carrier density was measured for graphene on BN/sapphire compared to sapphire substrates. Through control of the MOCVD process, BN films with roughness ranging from <0.1 nm to >1 nm were grown and used to study the effects of substrate roughness on graphene transport. Arrays of graphene field effect transistors were fabricated on 2" BN/sapphire substrates demonstrating scalability and device performance enhancement.
研究了通过金属有机化学气相沉积（MOCVD）在蓝宝石上生长的晶圆级（2英寸）氮化硼（BN）作为石墨烯的弱相互作用介电衬底，结果表明其传输性能优于传统的蓝宝石和SiO/Si衬底。通过化学气相沉积生长的石墨烯被转移到BN/蓝宝石衬底上，使用拉曼光谱和霍尔效应测量对30多个样品进行评估。与蓝宝石衬底相比，在BN/蓝宝石上的石墨烯测量到霍尔迁移率提高了两倍多，面载流子密度降低了10倍。通过控制MOCVD工艺，生长出粗糙度范围从<0.1nm到>1nm的BN薄膜，并用于研究衬底粗糙度对石墨烯传输的影响。在2英寸BN/蓝宝石衬底上制造了石墨烯场效应晶体管阵列，展示了其可扩展性和器件性能的提升。
