Barrier Inhomogeneity and Electrical Properties of InN Nanodots/Si Heterojunction Diodes.

The electrical transport behavior of n-n indium nitride nanodot-silicon (InN ND-Si) heterostructure Schottky diodes is reported here, which have been fabricated by plasma-assisted molecular beam epitaxy. InN ND structures were grown on a 20 nmInN buffer layer on Si substrates. These dots were found to be single crystalline and grown along [0 0 0 1] direction. Temperature-dependent current density-voltage plots (J-V-T) reveal that the ideality factor (η) and Schottky barrier height (SBH) (ΦB) are temperature dependent. The incorrect values of the Richardson constant (A**) produced suggest an inhomogeneous barrier. Descriptions of the experimental results were explained by using two models. First one is barrier height inhomogeneities (BHIs) model, in which considering an effective area of the inhomogeneous contact provided a procedure for a correct determination of A**. The Richardson constant is extracted ~110 A cm-2 K-2 using the BHI model and that is in very good agreement with the theoretical value of 112 A cm-2 K-2. The second model uses Gaussian statistics and by this, mean barrier height Φ0 and A** were found to be 0.69 eV and 113 A cm-2 K-2, respectively. [ABSTRACT FROM AUTHOR]