Highlights

Author(s): Antoine Kahn and David Cahen (Weizmann Inst.)

Electronic transport through a junction formed between silicon (Si), a monolayer of alkyl chains (C₁₄H₂₉) self-assembled on Si, and a metal (M) is dominated by thermionic emission above the semiconductor barrier and tunneling through the insulating molecular layer [1]. This team of PCCM and Weizmann investigators recently showed [2] that exposing the alkyl monolayers to electron irradiation induces new states between the occupied and unoccupied states of the pristine alkyl chain, evidently through the creation of C=C double bonds and C-C crosslinks since the overall layer density is unaffected. These states strongly affect electronic transport through the monolayer, suggesting a way to significantly extend the use of monolayers in molecular electronics.

J-V curves for n-Si-C₁₄H₂₉/Hg junctions, (red) non-irradiated monolayer, (black) freshly irradiated, (blue) irradiated monolayer remeasured after 1 week. Bias is applied to the Si, and the Hg drop is grounded.

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Related Publication(s):

[1] A. Salomon, T. Boecking, C.K. Chan, F. Amy, O. Girshevitz, D. Cahen, and A. Kahn, “How do electronic carriers cross alkyl monolayers?”, Phys. Rev. Lett., 95, 266807 (2005).

[2] O. Seitz, A. Vilan, H. Cohen, C. Chan, J. Hwang, A. Kahn, and D. Cahen, “Effect of doping on electronic transport through molecular monolayer junctions”, J. Am. Chem. Soc., 129, 7494-7495 (2007).