The influence of metal work function on electrical properties of metal/ a-SiC:H Schottky diodes

✍ Scribed by L. Magafas; N. Georgoulas; A. Thanailakis

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 515 KB
• Volume: 28
• Category: Article
• ISSN: 0026-2692
• DOI: 10.1016/s0026-2692(96)00077-8

✦ Synopsis

Electrical properties of Schottky diodes on rf sputtered a-SiC:H thin films for different metals (Mg,In,Al,Pd) were investigated. The M(=Mg,In,A1,Pd)/a-SiC:H Schottky diodes were found to exhibit very good rectification properties, with a turn-on voltage varying from 0-4 to 0-8V, depending on the top metal used, and a reverse current density lower than 10-gA/cm 2 with a reverse break down voltage, V3, approximately equal to 15V. The ideality factor, ~/, was found to be 1.34-0.1. This, combined with the temperature dependence of I-V characteristics, indicates that thermionic emission is most likely the dominant transport mechanism. A linear increase of barrier height at room temperature, ~%RT, with increasing metal work function, ~0r~, was obtained, suggesting that a-SiC:H exhibits the same type of conductivity (n-type) as that found for non-hydrogenated a-SiC. Pd/a-SiC:H Schottky diodes were found to exhibit linear room temperature log I vs V characteristics, over eight orders of magnitude, making these devices suitable for many applications.