Structures and field emission characteristics of ion irradiated silicon nanowire arrays.
Silicon nanowire (SiNW) arrays irradiated by energetic Si ions were fabricated by metal vapor vacuum arc (MEVVA) ion implantation method. Hetero-structure of amorphous/crystalline nanowire was formed in which structure of the implanted region on the top of the nanowires was amorphous while the structure of unimplanted region on the bottom remained crystal. Field emission (FE) properties of the SiNW arrays could be improved and modulated by different implantation doses. A low turn-on field of 4.63 V/microm was observed in the SiNWs irradiated by 21 keV Si ion with a dose of 7.86 x 10(16)/cm2, and the applied field for the emission current density reaching 100 microA/cm2 is only 5.52 V/microm. The main reason for the efficient emission is attributed to the formation of amorphous SiNWs and structure defects after implantation. The ion irradiated SiNWs after post-annealing at high temperature had better FE property due to eliminating the restrain effect to electrons.
Key Laboratory of Beam Technology and Material Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875, P. R. China.
Fei
F
Zhao
Jian-hua
JH
Deng
Dan-dan
DD
Zhao
Ke-fan
KF
Chen
Guo-an
GA
Cheng
Rui-ting
RT
Zheng