In-Ga-Zn-O MESFET with transparent amorphous Ru-Si-O Schottky barrier

• Published in: Physica status solidi. PSS-RRL. Rapid research letters Vol. 8; no. 7; pp. 625 - 628
• Main Authors: Kaczmarski, Jakub, Grochowski, Jakub, Kaminska, Eliana, Taube, Andrzej, Jung, Wojciech, Piotrowska, Anna
• Format: Journal Article
• Language: English
• Published: Berlin WILEY-VCH Verlag 01-07-2014; WILEY‐VCH Verlag; Wiley Subscription Services, Inc
• Subjects: amorphous oxide semiconductors; In−Ga−Zn−O; metal−semiconductor field-effect transistors; Schottky barriers; Semiconductors; Solid state physics; Transistors; transparent electronics
• ISSN: 1862-6254; 1862-6270
• DOI: 10.1002/pssr.201409124

Rectifying transparent amorphous Ru–Si–O Schottky contacts to In–Ga–Zn–O have been fabricated by means of reactive sputtering without any annealing processes nor semiconductor surface treatments. The ideality factor, effective Schottky barrier height and rectification ratio are equal to 1.6, 0.9 eV and 105 A/A, respectively. Ru–Si–O/In–Ga–Zn–O Schottky barriers were employed as gate electrodes for In–Ga–Zn–O metal–semiconductor field‐effect transistors (MESFETs). MESFET devices exhibiting on‐to‐off current ratio at the level of 103 A/A in a voltage range of 2 V, with subthreshold swing equal to 420 mV/dec were demonstrated. A channel mobility of 7.36 cm2/V s was achieved. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The novel transparent amorphous material Ru–Si–O with high work function (5.3 eV) is utilized as rectifying Schottky contact to form gate electrode of metal–semiconductor field‐effect transistors (MESFETs) with amorphous In–Ga–Zn–O active layer. Ru–Si–O/In–Ga–Zn–O structures are electrically and optically characterised. Our device operates in a narrow voltage range of 2 V, which makes it promising for use in low‐power consumption transparent integrated circuits.