Evaluation of the perfection of the Pd-InP Schottky interface from the energy viewpoint of hydrogen adsorbates

In general, two factors, i.e. the Schottky barrier height (Phi(Bn)) and the ideality factor (n) based on thermionic emission current-voltage (I-V) analysis, are used to evaluate the interfacial quality of Schottky diodes. In this paper, we propose an alternative method, different from the traditional I-V analysis, to evaluate the perfection of the Pd-InP Schottky interface. By introducing hydrogen adsorbates into the Pd-InP interface, it is found that the interfacial hydrogen energy state can reflect the perfection of the Pd-InP Schottky interface. The Pd/InP Schottky diode with a more perfect interface infers that the interfacial hydrogen adsorbates possess higher energy states. Compared with the thermal evaporated Pd-InP Schottky interface, the electroless plated diode exhibits superior I-V characteristics. Also, it demonstrates that hydrogen adsorbates at the electroless plated Pd-InP interface truly possess higher energy states, e.g., Gibbs energy (G) and enthalpy (H). Therefore, this proposed method can be used for evaluating the perfection of the Pd-InP Schottky interface. Also, the result is consistent with that obtained by traditional I-V analysis.