Annealing induced hysteresis suppression for TiN/HfO₂/GeON/p-Ge capacitor

Abstract

In this paper the annealing effects in N 2 on the electrical characteristics of a TiN/HfO 2 /GeON/p-Ge capacitor are investigated. Well behaved capacitance-voltage curves were obtained for the sample annealed at 400 • C for 3 min in N 2 . A negligible hysteresis was demonstrated comparing with a hysteresis of 0.5 V for the as-deposited sample. The suppression of hysteresis is attributed to the reduction of electron traps in the dielectric layer, which is verified by the MOS pulse method. Besides, the interface states' density is also greatly reduced by annealing in N 2 and confirmed by the conductance method.

Fermi Level Depinning Failure for Al/GeO2/Ge Contacts

“…3b shows an abrupt Al/GeO x N y interface. The thickness of the amorphous GeO x N y layer is about 1 nm which agrees well with our MOS capacitors data 13,25 In contrast, the interfacial layer thickness for Al/GeO 2 /n-Ge sample seems to be about 3.5 nm, which is much larger than the data of 1-2 nm revealed in our previous MOS capacitors work using a similar passivation process. 14 For Al/GeO 2 /n-Ge contacts, it is believed that the penetration of Al into the interfacial layer is causing the failure of FL depinning.…”

Formation and characterization of holmium oxide on germanium‐based metal‐oxide‐semiconductor capacitor

“…In addition, it is well documented that Ge 3 N 4 is more thermodynamically stable with highk permittivity in counter to GeO 2 . 37,38,51 Accordingly, the IL rich with Ge-N bonding rather than Ge-O compounds will exhibit a more thermally stable IL. Based on this assumption and above discussion it can be suggested that a more thermally stable IL was formed for 10 and 15 minutes oxidation/nitridation since these samples consist of more stoichiometric Ge 3 N 4 compound and F I G U R E 7 Deconvoluted Ge 3d narrow scan spectra for different oxidation/nitridation durations (5, 10, 15, and 20 minutes) fewer sub-stoichiometric GeO 2 , GeO x , and GeO than those of 5 and 20 minutes samples.…”

“…Consequently, the presence of a large amount Ge 2+ (GeO) and Ge 4+ (GeO 2 ) will cause sharp degradation on the thermodynamic stability of the gate stack. In addition, it is well documented that Ge 3 N 4 is more thermodynamically stable with high‐ k permittivity in counter to GeO 2 37,38,51 . Accordingly, the IL rich with Ge‐N bonding rather than Ge‐O compounds will exhibit a more thermally stable IL.…”

“…Furthermore, surface nitridation with the incorporation of NH 3 and N 2 has been widely studied for Ge surface passivation 33‐38 . It was found that incorporation of nitrogen improves the interface quality, dielectric constant, and electrical properties of high‐ k /Ge.…”

“…Furthermore, surface nitridation with the incorporation of NH 3 and N 2 has been widely studied for Ge surface passivation. [33][34][35][36][37][38] It was found that incorporation of nitrogen improves the interface quality, dielectric constant, and electrical properties of high-k/Ge. This improvement has been attributed to Ge-N/Ge-O-N IL which effectively alleviated the impurity diffusion between high-k and Ge substrate.…”