Ballistic electron microscopy of a metal molecule interface

We present studies on a Ag/ HS–(CH2)4–T3–H (T3C4SH)/ Au diode using nanometer scale resolution, ballistic electron emission microscopy (BEEM). Images show spatially non-uniform carrier injection. A WKB calculation is carried out and compared with the experimental data. The results indicate that molecular levels are being accessed in the BEEM experiment, since the measured currents are larger than purely tunneling contribution. Our results are consistent with previously published results on a similar molecule [ 1]. Physical origins of the non-uniform carrier injection and its implications are discussed.