Investigation of the effects of GaAs substrate orientations on the electrical properties of sulfonated polyaniline based heterostructures

• Published in: Applied surface science 2020-02, Vol.504, p.144315, Article 144315
• Main Authors: Jameel, Dler Adil, Marroquin, John Fredy Ricardo, Aziz, Mohsin, Al Saqri, Noor Alhuda, Jum'h, Inshad, Telfah, Ahmad, Henini, Mohamed, Felix, Jorlandio Francisco
• Format: Article
• Language: English
• Subjects: (1 0 0) GaAs; (3 1 1)A GaAs; (3 1 1)B GaAs; C-V; DLTS; Hybrid device; I-V
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2019.144315

In this work we present a detailed study of the influence of the GaAs substrate orientation on the electrical properties of heterojunctions based on GaAs and sulfonated polyaniline (SPAN) using Current-Voltage (I-V), Capacitance-Voltage (C-V), Deep-Level Transient Spectroscopy (DLTS) and Laplace DLTS techniques. Three different GaAs substrate orientations have been investigated, namely (1 0 0), (3 1 1)A and (3 1 1)B. The I-V results revealed that the turn-on voltage (Von) of SPAN/(3 1 1)B GaAs heterojunction is higher than that for SPAN/(1 0 0) GaAs and SPAN/(3 1 1)A GaAs heterojunctions. The DLTS results showed that the number of electrically active defects present in devices based on the lower index (1 0 0) plane of GaAs substrate is higher than those of higher index (3 1 1)A and (3 1 1)B GaAs substrates, corroborating with I-V results. In order to investigate the role of interface states, capacitance-frequency measurements were performed in forward bias on all three devices.