In situESR Observation of Interface Dangling Bond Formation Processes During UltrathinSiO2Growth On Si(111)

Abstract

We report the formation processes of interface dangling bonds (Pb centers) during initial oxidation of a clean Si(111) surface using an ultrahigh-vacuum electron-spin-resonance technique. At the oxidation of one or two Si layer(s), the Pb center density reached around 2.5-3.0 x 10(12) cm(-2), which is the same density as in the case of thick SiO2. This result shows that the Pb center density does not originate from the long-range accumulation of the structural stress between two materials, but from the chemical reactions of oxidation within a few Si atomic layers.

Theoretical Study of Excess Si Emitted from Si-oxide/Si Interfaces

“…If these dangling bonds remain even after thermal treatments, they should act as the E 0 centers and charge traps in the oxide 22) or as the P b centers and charge traps at the interface. [23][24][25][26] Even if those dangling bonds are terminated by H atoms during the thermal treatments, they could be latent charge traps and be activated by some electrical excitation. Since these remaining dangling bonds or H-terminated dangling bonds are often discussed as the source of the charge traps and the trigger of the dielectric breakdown of the gate oxide, [27][28][29][30][31][32][33][34] further investigation on the excess Si around the interface will lead us toward the fine control of the dielectric reliability of the gate oxide.…”

Spin noise fluctuations from paramagnetic molecular adsorbates on surfaces

“…Moreover, the natural abundance of 29 Si ͑I =1/2͒ is low ͑4%͒ and most of the Pb centers on SiO 2 surface do not present hyperfine coupling. [52][53][54] The frequency at which the signal can be detected might also be affected by local electric field oscillations. However, this is true for Pb centers on SiO 2 rather than in organic radicals as reported in literature.…”

Size‐Controlled Si Nanocrystals Using the SiO/SiO 2 Superlattice Approach: Crystallization, Defects, and Optical Properties

“…At the (110) Si/SiO 2 interface again, only one type, the P b variant, is observed [31]. Thus, all three variants were shown to be interfacial trivalent Si centers [32], naturally occurring, for standard oxidation temperatures (800-960 C), in areal densities of [P b ] $ 5 Â 10 12 cm À2 [33][34][35][36] and [P b0 ], [P b1 ] $ 1 Â 10 12 cm À2 [36].…”