Barrier characteristics and interface properties of Au/Ti/n-InAlAs Schottky contacts. (February 2018)

• Record Type: Journal Article
• Authors: Chistokhin, I.B.; Aksenov, M.S.; Valisheva, N.A.; Dmitriev, D.V.; Kovchavtsev, A.P.; Gutakovskii, A.K.; Prosvirin, I.P.; Zhuravlev, K.S.
• Is Part Of: Materials science in semiconductor processing. Volume 74(2018)
• Page Start: 193
• Page End: 198
• Publication Date: 2018-02
• Subjects: Semiconductors -- Periodicals; Integrated circuits -- Materials -- Periodicals; Semiconducteurs -- Périodiques; Circuits intégrés -- Matériaux -- Périodiques; Electronic journals; 621.38152
• DOI: 10.1016/j.mssp.2017.10.014
• Languages: English
• ISSNs: 1369-8001

Abstract

Abstract: The InAlAs surface morphology (AFM), chemical composition (XPS) and the Ti/InAlAs interface structure (HREM), during the Au/Ti/n-In0.52 Al0.48 As/InP(001) mesa-structure Schottky barrier formation, were studied. The current-voltage ( I-V ) dependences analysis of the formed Schottky barrier in the temperature range of 100–380 K was carried out. It was shown that the I-V dependences are well described by the thermionic emission theory at temperatures above 200 K with the ideality factor and the barrier height close to 1.09 and 0.7 eV, respectively. At temperatures below 200 K, the I-V behavior is attributed to the Schottky barrier anomalies, which are explained by the existence of nanometer-sized patches with a low barrier height having a Gaussian distribution (Tung model). According to this model, the temperature dependences of the barrier height and ideality factor were described with the following parameters: the homogeneous barrier height of 0.88 eV and standard deviation of 10 −4 cm 2/3 V 1/3 . In the analysis of the modified Richardson plot, the Richardson constant (10.7 Acm −2 K −2 ) and the area fraction (24%), occupied by the patches with a low barrier height and diameter ~80 nm, were calculated. The patches appearance is explained by the presence of the spikes detected on the InAlAs surface by the AFM method.