Resonant tunneling through nano-size quantum dots embedded in amorphous tissues

A diode containing hydrogenated nano-crystalline silicon film, in which nan o-size silicon quantum dots are embedded in an amorphous silicon matrix, wa s fabricated and staircases were observed on its I-V curves and discontinuo us capacitance on its C-V curve. There are two distinct regions on the I-V curves of the diode: (i) the sequential tunneling region, where current inc reases monotonously with increasing negative bias; (ii) the resonant tunnel ing region, where the current increases dramatically with increasing negati ve bias and three quantum staircases appear. It is found that the steps and discontinuous capacitance an related to grains of the deposited film. A qu alitative explanation of this physical phenomenon is proposed in terms of t he material structural characteristics. (C) 2000 Elsevier Science B.V. All rights reserved.