摘要Modulation of Schottky barrier height (SBH) is successfully demonstrated by a germanidation-induced dopant segregation technique. The barrier height of NiGe/Ge Schottky diodes is modulated by 0.06-0.15eV depending on annealing temperature. The results show the change of SBH is not attributed to the phase change of nickel germanides but to dopant segregation at the interface of germanides/germanium which causes the upward conduction energy band. In addition, we first observe a Raman peak at about 217cm-1 corresponding to NiGe, which has not been reported till now. The surface morphology of nickel germanides can be improved by BF2 implantation before germanidation. The results may provide guidelines for the design of Schottky source/drain germanium-based devices.
Abstract:Modulation of Schottky barrier height (SBH) is successfully demonstrated by a germanidation-induced dopant segregation technique. The barrier height of NiGe/Ge Schottky diodes is modulated by 0.06-0.15eV depending on annealing temperature. The results show the change of SBH is not attributed to the phase change of nickel germanides but to dopant segregation at the interface of germanides/germanium which causes the upward conduction energy band. In addition, we first observe a Raman peak at about 217cm-1 corresponding to NiGe, which has not been reported till now. The surface morphology of nickel germanides can be improved by BF2 implantation before germanidation. The results may provide guidelines for the design of Schottky source/drain germanium-based devices.
[1] Trumbore F A 1960 Bell Syst. Tech. J. 39 205 [2] Chui C and Saraswat K C 2004 International Conference on Integrated Circuit Design and Techno (Austin, Texas 17--20 May 2004) p 245 [3] Lepselter M P and Sze S M 1968 Proc. IEEE 561400 [4] Kedzierski J, Xuan P, Anderson E H, Bokor J, King T J andHu C 2000 IEDM Tech. Dig. (San Francisco, CA 11--13 December 2000) p 57 [5] Guo J and Lundstrom M S 2002 IEEE Trans. Electron.Devices 49 1897 [6] Geng L, Magyari-Kope B, Zhang Z Y and Nishi Y 2009Chin. Phys. Lett. 26 037306 [7] Yue S.L., Lu Q, Shi CY, Yang H X, Wang Q, Xu P and Gu C Z2006 Chin. Phys. Lett. 23 678 [8] Jang M, Kim Y, Shin J, Lee S and Park K 2004 Appl.Phys. Lett. 84 741 [9] Snyder J P, Helms C R and Nishi Y 1995 Appl. Phys.Lett. 67 1420 [10] Connelly D, Faulkner C, Grupp D E and Harris J S 2004 IEEE Trans. Nanotechnol. 3 98 [11] Tao M, Udeshi D, Basit N, Maldonado E and Kirk W P 2003 Appl. Phys. Lett. 82 1559 [12] Zhao Q T, Breuer U, Rije E, Lenk S and Mantl S 2005 Appl. Phys. Lett. 86 062108 [13] Kinoshita A, Tsuchiya Y, Yagishita A, Uchida K and Koga J2004 VLSI Symp. Tech. Dig. (Honolulu 15--17 June 2004) p 168 [14] Wong A S, Chi D Z, Loomans M, Ma D, Lai M Y, Tjiu W C,Chua S T, Lim C W and Greene J E 2002 Appl. Phys. Lett. 81 5138 [15] Cheung S K and Cheung NW 1986 Appl. Phys. Lett. 49 85 [16] JCPDS diffraction file 07-0297 (NiGe) [17] Jin L J, Pey K L, Choi W K, Fitzgerald E A, Antoniadis DA, Pitera A J, Lee M L, Chi D Z and Tung C H 2004 Thin SolidFilms 462--463 151