Distribution of barrier heights in metal/n-InAlAs Schottky diodes from current–voltage–temperature measurements

• Published in: Materials science in semiconductor processing Vol. 26; pp. 431 - 437
• Main Authors: Hamdaoui, N., Ajjel, R., Salem, B., Gendry, M.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-10-2014; Elsevier
• Subjects: Applied sciences; Barriers; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Constants; Diodes; Electron and ion emission by liquids and solids; impact phenomena; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronics; Exact sciences and technology; Gaussian distribution; Inhomogeneous barrier height; Interfaces; I–V–T; Physics; Schottky contact; Schottky diodes; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Semiconductors; Serials; Standard deviation; Straight lines; Surface double layers, schottky barriers, and work functions; Thermionic emission; Gaussian distribution; Inhomogeneous barrier height; I–V–T; Schottky contact; Voltage current curve; Electric contact; Ideality; Thermionic emission; I―V―T; Standard deviation; Barrier height; Schottky barrier diode; Schottky barrier; Electrical characteristic
• ISSN: 1369-8001; 1873-4081
• DOI: 10.1016/j.mssp.2014.05.043

The current–voltage characteristics of metal/n-InAlAs Schottky diodes were determined in the temperature range 90–300K. Analysis of the measured characteristics allows the determination of the electrical parameters, the saturation current I0, the ideality factor n and the serial resistance Rs. The results show an increase of the Schottky barrier height φB0 and a decrease of the ideality factor n both with the increase of the temperature. The characteristics have been interpreted based on the thermionic emission (TE) mechanism with Gaussian distribution of the barrier heights of φ¯b0 is 0.96eV and standard deviation σso is equal to 0.128V. In addition, the ln(I0/T2) vs. 1/T plot yields the effective Richardson constant of 4.65×10−3Acm−2K−2 for the metal/InAlAs diode which is lower than the known value of 10.1Acm−2K−2 for InAlAs. The modified Richardson plot shows a straight line relationship between ln(Is/T2)–(q2σ2so/2k2T2) vs. 1000/T, and gives a value of A*=9.2Acm−2K−2.