Hydrogen migration under avalanche injection of electrons in Si metal-oxide-semiconductor capacitors

Abstract

Aluminum/silicon dioxide/silicon capacitors in which the oxide has been grown thermally under ultra-dry (≲1 ppm H2O) conditions and subsequently treated by low temperature water diffusion have been characterized electrically and chemically. Avalanche injection of electrons has been observed to produce the complex charging behavior previously observed in similar systems, which includes electron trapping and interface positive charge generation. Secondary ion mass spectrometry depth profiling of these structures has shown that electron injection also results in hydrogen transport. This is the first direct observation of hydrogen redistribution under the influence of an electron current. We demonstrate a linear relationship between injected charge fluence and areal density of hydrogen localized at the SiO2/Si interface. These results indicate that hydrogen release correlates with interface state generation, but not with bulk oxide trapping.

Behavior of hot hole stressedSiO2/Si interface at elevated temperature

“…It is well known that considerable amount of hydrogen can be released during electron injection. 19 These hydrogen species are not effective in annealing the states during the stress at room temperature. However, they can anneal the states if an elevated temperature is used after the stress.…”

Injection Spectroscopy of Thin Layers of Solids

“…possible involvement in the charge transport or trapping. At the same time there is plenty of experimental evidence indicating hydrogen as an important factor of charging, for instance of SiO 2 insulating films and their interfaces (Nicollian et al, 1971;Feigl et al, 1981;Gale et al, 1983;Stahlbush et al, 1993;de Nijs et al, 1994;Cartier and Stathis, 1995;Afanas'ev et al, 1995a,b;Afanas'ev and Stesmans, 1998a,b, 1999b, 2000a,b, 2001aVanheusden et al, 1995Vanheusden et al, ,1997Rivera et al, 2002). Therefore, identification of hydrogen-related charge transport and trapping interaction is gaining more importance as novel oxide-based insulators attract increasing attention (see, e.g., Afanas'ev and Stesmans, 2002 for some high-permittivity insulating metal oxides.…”

Suppression of hydrogen-ion drift into underlying layers using plasma deposited silicon oxynitride film during high-density plasma chemical vapor deposition

“…The depth profiles of the hydrogen concentrations in thermal oxides can be divided into three zones, Zone-1: a rapidly decreasing concentration adjacent to the p-SiO x N y H z film/thermal oxide interface in the depth range of 50 to 100 nm, Zone-2: a concentration of bulk thermal oxide in the depth range of 20 to 50 nm, Zone-3: a peak at the thermal oxide/silicon substrate interface. In Zone-1, it is difficult to measure the hydrogen concentrations, because the SIMS measurements were conducted from the surface side and an artificial tailing of the hydrogen profiles caused by an atomic knock-on process could not be avoided [7][8][9][10]. Because the resolution of the depth profile for the upper interfaces of the thermal oxides is degraded, the hydrogen concentrations in Zone-1 are ignored.…”