Novel methods to incorporate deuterium in the MOS structures

IEEE Trans. Semicond. Manufact.

Yuan

et al. 2003

The instantaneous switch-off of the gas precursors during the ramp-down cycle in a spike ramp process is demonstrated to be an effective method to enhance the reliability of rapid thermal oxide. Due to the slow ramp-down rate (60 C-90 C/s) of a rapid thermal process, the oxidation during the slow ramp-down cycle may produce the inferior oxide, especially for ultrathin oxide. To avoid the oxidation in the slow ramp-down cycle, the oxidation precursor (oxygen) is switched off during the ramp-down cycle. The reliability of resulting oxide without oxidation during the ramp-down cycle is enhanced as compared with the conventional oxide, which is still oxidized during the ramp-down cycle.

Section: Resultsmentioning

confidence: 99%

Reliability improvement of rapid thermal oxide using gas switching

IEEE Trans. Semicond. Manufact.

Yuan

et al. 2003

“…Recently, an alternative process during which the interface traps are passivated by deuterium instead of hydrogen was demonstrated [3,4]. This phenomenon can be understood as a kinetic isotope effect.…”

Section: Introductionmentioning

confidence: 99%

Deuterium implantation at the back-end of line for the improvement of gate oxide reliability in nano-scale MOSFETs

2007 7th IEEE Conference on Nanotechnology (IEEE NANO)

2007

This paper is focused on the improvement of MOS device reliability related to deuterium incorporation in gate oxide. The injection of D + ions into the gate oxide film was achieved through low-energy implantation at the back-end of line (BEOL) for the purpose of the passivation of dangling bonds at SiO 2 /Si interface and the generation of deuterium bonds in SiO 2 bulk. Device parameter variations, as well as the gate leakage current, depend on the degradation of gate oxide and, compared to corresponding hydrogen incorporation, are improved by deuterium incorporation. However, when the concentration of deuterium is redundant in gate oxide, excess traps are generated and degrade the performance. Our result suggests the novel method to incorporate deuterium in the MOS structure for the reliability.

“…Recently, an alternative process during which the interface traps are passivated by deuterium instead of hy-drogen has been demonstrated [6,7]. This phenomenon can be understood as a kinetic isotope effect.…”

Section: Introductionmentioning

confidence: 99%

Study for the Reliability of Nano-Scale MOS Devices that Experienced Implantation of Hydrogen or Deuterium at the Back-End of the Process Line

Lee²,

Do³

et al. 2007

J. Korean Phys. Soc.

This paper is focused on the improvement of MOS device reliability related to hydrogen or deuterium atoms. The injection of these atoms into the gate oxide film was achieved through lowenergy implantation at the back-end of a line for the purpose of passivation of dangling bonds at the SiO2/Si interface. Experimental results are presented for the degradation of the 3-nm-thick gate oxide (SiO2) under both hot-carrier-injection (HCI) and constant voltage stresses using p-and n-MOSFETs. Device parameters, as well as the gate leakage current, depend on the degradation of gate oxide and, compared to corresponding hydrogen incorporation, are improved by deuterium incorporation. The Si-D bonds (instead of Si-H) in the SiO2 film were found to play a major role in suppressing the generation of oxide traps. However, when the concentration of deuterium is redundant in the gate oxide, excess traps are generated and degrade the performance. Our result suggests a novel method to incorporate deuterium in the MOS structure for reliability.