Effect of polysilicon gate on the flatband voltage shift and mobility degradation for ALD-Al2O3 gate dielectric

J. H. Lee, K. Koh, N. I. Lee, M. H. Cho, Y. K. Kim, J. S. Jeon, K. H. Cho, H. S. Shin, M. H. Kim, K. Fujihara, H. K. Kang, J. T. Moon

Research output: Contribution to journalConference articlepeer-review

89 Citations (Scopus)


Al2O3 (EOT=22.7 Å) gate dielectric layer formed by Atomic Layer Deposition (ALD) process have been characterized for sub-100nm CMOS devices. The gate leakage current was 3 orders of magnitude lower than that of SiO2 and the hysteresis of C-V curve was not observed. However, the negative fixed charge induced the flat band voltage (Vfb) shift and degraded the channel mobility of MOS transistor. The Vfb shift was reduced and channel mobility was improved by applying P+ gate by BF2 implantation. It is suggested that the phosphorous diffused from gate polysilicon has a role of network modifier in Al2O3 film and formation of the Al-O- dangling bond which may be ascribed to negative fixed charge.

Original languageEnglish
Pages (from-to)645-648
Number of pages4
JournalTechnical Digest - International Electron Devices Meeting
Publication statusPublished - 2000
Event2000 IEEE International Electron Devices Meeting - San Francisco, CA, United States
Duration: 2000 Dec 102000 Dec 13

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Electrical and Electronic Engineering
  • Materials Chemistry


Dive into the research topics of 'Effect of polysilicon gate on the flatband voltage shift and mobility degradation for ALD-Al<sub>2</sub>O<sub>3</sub> gate dielectric'. Together they form a unique fingerprint.

Cite this