Electronic properties of Al/MoO3/p-InP enhanced Schottky barrier contacts

• Barrier heights of Al/p-InP Schottky diodes were enhanced by inserting a MoO3 layer.
• Electrical properties of the Al/MoO3/p-InP Schottky diodes were investigated.
• Gaussian distribution was employed to explain the interface barrier inhomogeneity.

The Al/MoO3/p-InP metal/insulator/semiconductor (MIS) and Al/p-InP metal/semiconductor (MS) Schottky Barrier Diodes (SBDs) have been fabricated to confirm Schottky barrier heights (SBHs) enhancement by inserting an ultrathin insulator layer between the MS contact. The current-voltage (I-V) and capacitance-voltage (C-V) measurements have been performed in the temperature range of 310–400 K. The modified Richardson plot gives the Richardson constant of 66.16 and 59.07 A cm− 2 K− 2 for Al/MoO3/p-InP MIS SBDs and Al/p-InP MS SBDs, respectively, which are both close to the theoretical value known for p-InP (60 A cm− 2 K− 2). The SBHs for these two diodes have decreased with decreasing temperature while the ideality factor values have increased with decreasing temperature, obeying the barrier height Gaussian distribution model based on thermionic emission current theory. In addition, the experimental barrier height shows an obvious enhancement and ideality factor does not show a considerable increase, verifying that MoO3 is a good candidate for the interfacial insulator layer.