High-dielectric-constant hafnium silicate insulator for low-voltage pentacene field-effect transistors

✍ Scribed by Yan, Hu ;Kagata, Tsubasa ;Arima, Susumu ;Sato, Hiroshi ;Okuzaki, Hidenori

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 478 KB
• Volume: 205
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200824297

✦ Synopsis

Abstract

We prepared HfSiO__~x~__ on a heavily doped n‐type silicon wafer by sputtering of a HfSi (50:50 at%) target using Ar:N~2~:O~2~ as carrier gas. The HfSiO__~x~__ layer thus prepared was characterized by XPS, XRD, STEM and C –F measurements, indicating that the layer mainly consisted of 100 nm thick amorphous HfSiO~5~ with a dielectric constant ϵ~r~ = 7.7. The leakage current density was 1 nA/cm^2^ at an electric field of 2 MV/cm. We first fabricated top‐contact pentacene FETs using the high dielectric constant hafnium silicate as an insulator, coupled with a polymer microfiber‐based channel patterning technique. The pentacene FET showed well‐saturated output characteristics at low driving voltages, i.e. V~D~ = –10 V and V~G~ = –10 V, and hole mobility of 0.02 cm^2^/V s and on/off current ratio of 2600. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)