AVS 53rd International Symposium
    Electronic Materials and Processing Friday Sessions
       Session EM-FrM

Paper EM-FrM2
Structural Dependence of Charge Transport in Organic Molecular Films

Friday, November 17, 2006, 8:20 am, Room 2001

Session: Molecular Electronics
Presenter: Y. Qi, UC Berkeley and Lawrence Berkeley National Laboratory
Authors: Y. Qi, UC Berkeley and Lawrence Berkeley National Laboratory
B.L.M. Hendriksen, UC Berkeley and Lawrence Berkeley National Laboratory
D. Esteban, UC Berkeley and Lawrence Berkeley National Laboratory
I. Ratera, UC Berkeley and Lawrence Berkeley National Laboratory
M. Salmeron, UC Berkeley and Lawrence Berkeley National Laboratory
J.Y. Park, UC Berkeley and Lawrence Berkeley National Laboratory
F. Ogletree, UC Berkeley and Lawrence Berkeley National Laboratory
Correspondent: Click to Email
The charge transport properties and mechanical properties of alkanethiol and trans-stilbene based self-assembled molecules on Au(111) have been investigated by using a conducting probe atomic force microscope (CP-AFM) in ultrahigh vacuum. We found that there exists a clear correlation between them. The step-wise change previously found in alkanethiol molecular film thickness and friction upon pressing the molecules with atomic force microscope tip was observed in the tip-sample current. Increasing of tip-sample current is mainly due to tilt of molecules under the high pressure. We measured the decay constant ß=0.58/Å for hexadecanethiol, significantly smaller than decay constant (~ 1/Å) that is caused by shortening the alkanethiol molecule length. Our calculation based on the two-pathway model is in good agreement with the current measurement upon molecular tilt. We will discuss the new scheme of Field Effect Transistor (FET) configuration that allows us to measure the electron transport parallel to the self-assembled monolayer.