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Title: Key Technologies for Ultra High Dose CMOS Applications

Abstract

The trend towards shrinking advanced microelectronic Logic and DRAM devices will require ultra high dose implantation. One ultra high dose application in DRAM, being rapidly adopted in production is Dual Poly Gate (DPG). Three main challenges existed for the adoption of this high dose dual poly gate (DPG) doping applications: monitoring of high dose implantation, photoresist stripping and maintaining high throughput. In this paper we present how these challenges have been addressed. VSEA's plasma doping (PLAD) tool offers several unique advantages for DPG applications. When compared to conventional or molecular beam line implanters or other immersion techniques, PLAD delivers 3 to 7 times higher throughput (compared to traditional ion implanter) without dopant penetration through the thin doped polysilicon layer into the gate oxide. It also improves P{sup +} poly silicon DPG device properties at superior throughput. In this work we demonstrate how hot spray photoresist strip processing eliminates the need for multiple-tools required for wet+ash+wet process. In addition to PLAD's patented in-situ dose control metrology we also demonstrate an ex-situ high dose implantation metrology using spectroscopic ellipsometer (SE) and spectroscopic reflectometer (SR). The technique shows good correlation (R{sup 2}{approx}0.99) between implant dose and damaged layer thickness.

Authors:
; ;  [1]; ; ; ; ; ; ;  [2]; ; ;  [3]; ; ;  [4]; ; ;  [5]
  1. Varian Semiconductor Equipment Associates, Inc., 35 Dory Road, Gloucester, MA 01930 (United States)
  2. Hynix Semiconductor, Inc., Ichon-si, Kyoungki-do, 467-701 (Korea, Republic of)
  3. Nanometrics, Inc., Milpitas, CA 95035 (United States)
  4. FSI International, Inc., Chaska, MN 55318 (United States)
  5. Varian Korea Ltd., Pyeongtaek-si Kyoungki-do 459-040 (Korea, Republic of)
Publication Date:
OSTI Identifier:
21251646
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1066; Journal Issue: 1; Conference: 17. international conference on ion implantation technology, Monterey, CA (United States), 8-13 Jun 2008; Other Information: DOI: 10.1063/1.3033574; (c) 2008 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ASHES; CURIUM OXIDES; DOPED MATERIALS; ELLIPSOMETERS; INTEGRATED CIRCUITS; ION IMPLANTATION; LAYERS; MOLECULAR BEAMS; SILICON

Citation Formats

Jeon, Y., Koo, I., Singh, V., Oh, J., Jin, S., Lee, J., Rouh, K., Ju, M., Jeon, S., Ku, J., Lee, S. B., Lee, S. W., Ok, M. T., Butterbaugh, J., Lee, A., Kim, K., Lee, S. W., Ju, K. J., and Park, J. W.. Key Technologies for Ultra High Dose CMOS Applications. United States: N. p., 2008. Web. doi:10.1063/1.3033574.
Jeon, Y., Koo, I., Singh, V., Oh, J., Jin, S., Lee, J., Rouh, K., Ju, M., Jeon, S., Ku, J., Lee, S. B., Lee, S. W., Ok, M. T., Butterbaugh, J., Lee, A., Kim, K., Lee, S. W., Ju, K. J., & Park, J. W.. Key Technologies for Ultra High Dose CMOS Applications. United States. doi:10.1063/1.3033574.
Jeon, Y., Koo, I., Singh, V., Oh, J., Jin, S., Lee, J., Rouh, K., Ju, M., Jeon, S., Ku, J., Lee, S. B., Lee, S. W., Ok, M. T., Butterbaugh, J., Lee, A., Kim, K., Lee, S. W., Ju, K. J., and Park, J. W.. 2008. "Key Technologies for Ultra High Dose CMOS Applications". United States. doi:10.1063/1.3033574.
@article{osti_21251646,
title = {Key Technologies for Ultra High Dose CMOS Applications},
author = {Jeon, Y. and Koo, I. and Singh, V. and Oh, J. and Jin, S. and Lee, J. and Rouh, K. and Ju, M. and Jeon, S. and Ku, J. and Lee, S. B. and Lee, S. W. and Ok, M. T. and Butterbaugh, J. and Lee, A. and Kim, K. and Lee, S. W. and Ju, K. J. and Park, J. W.},
abstractNote = {The trend towards shrinking advanced microelectronic Logic and DRAM devices will require ultra high dose implantation. One ultra high dose application in DRAM, being rapidly adopted in production is Dual Poly Gate (DPG). Three main challenges existed for the adoption of this high dose dual poly gate (DPG) doping applications: monitoring of high dose implantation, photoresist stripping and maintaining high throughput. In this paper we present how these challenges have been addressed. VSEA's plasma doping (PLAD) tool offers several unique advantages for DPG applications. When compared to conventional or molecular beam line implanters or other immersion techniques, PLAD delivers 3 to 7 times higher throughput (compared to traditional ion implanter) without dopant penetration through the thin doped polysilicon layer into the gate oxide. It also improves P{sup +} poly silicon DPG device properties at superior throughput. In this work we demonstrate how hot spray photoresist strip processing eliminates the need for multiple-tools required for wet+ash+wet process. In addition to PLAD's patented in-situ dose control metrology we also demonstrate an ex-situ high dose implantation metrology using spectroscopic ellipsometer (SE) and spectroscopic reflectometer (SR). The technique shows good correlation (R{sup 2}{approx}0.99) between implant dose and damaged layer thickness.},
doi = {10.1063/1.3033574},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1066,
place = {United States},
year = 2008,
month =
}
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