title: Growth and characterization of ternary AlGaN alloy nanocones across the entire composition range.
abstract: AlGaN ternary alloys have unique properties suitable for numerous applications due to their tunable direct band gap from 3.4 to 6.2 eV by changing the composition. Herein we report a convenient chemical vapor deposition growth of the quasi-aligned Al(x)Ga(1-x)N alloy nanocones over the entire composition range. The nanocones were grown on Si substrates in large area by the reactions between GaCl(3), AlCl(3) vapors, and NH(3) gas under moderate temperature around 700 °C. The as-prepared wurtzite Al(x)Ga(1-x)N nanocones have single-crystalline structure preferentially growing along the c-axis, with homogeneous composition distribution, as revealed by the characterizations of electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, and selected area electron diffraction. The continuous composition tunability is also demonstrated by the progressive evolutions of the band edge emission in cathodoluminescence and the turn-on and threshold fields in field emission measurements. The successful preparation of Al(x)Ga(1-x)N nanocones provides the new possibility for the further development of advanced nano- and opto-electronic devices.
authors.affiliation: Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, People's Republic of China.
authors.forename: Chengyu
authors.initials: C
authors.lastname: He
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wu
authors.forename: Xizhang
authors.initials: X
authors.lastname: Wang
authors.forename: Yongliang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Lijun
authors.initials: L
authors.lastname: Yang
authors.forename: Ning
authors.initials: N
authors.lastname: Liu
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhao
authors.forename: Yinong
authors.initials: Y
authors.lastname: Lu
authors.forename: Zheng
authors.initials: Z
authors.lastname: Hu