The effect of N_(2)-plasma-treated SiO_(2) interfacial layer on the interfacial and electrical characteristics of HfO_(2)/SiO_(2)/p-Si stacks grown by atomic layer deposition(ALD) was investigated.The microstructure a...The effect of N_(2)-plasma-treated SiO_(2) interfacial layer on the interfacial and electrical characteristics of HfO_(2)/SiO_(2)/p-Si stacks grown by atomic layer deposition(ALD) was investigated.The microstructure and interfacial chemical bonding configuration of the HfO_(2)/SiO_(2)/Si stacks were also examined by high-resolution transmission electron microscopy(HRTEM) and X-ray photoelectron spectroscopy(XPS).Compared with the samples without N2-plasma treatment,it is found that the samples with N2-plasma treatment have less oxygen vacancy density for SiO_(2) interfacial layer and better HfO_(2)/SiO_(2) interface.In agreement with XPS analyses,electrical measurements of the samples with N2-plasma treatment show better interfacial quality,including lower interface-state density(Dit,9.3 × 1011 cm^(-2)·eV^(-1) near midgap) and lower oxidecharge density(Q_(ox),2.5 × 1012 cm^(-2)),than those of the samples without N_(2)-plasma treatment.Additionally,the samples with N_(2)-plasma treatment have better electrical performances,including higher saturation capacitance density(1.49 μF·cm^(-2)) and lower leakage current density(3.2 × 10^(-6) A·cm^(-2) at V_(g)=V_(fb)-1 V).Furthermore,constant voltage stress was applied on the gate electrode to investigate the reliability of these samples.It shows that the samples with N_(2)-plasma treatment have better electrical stability than the samples without N_(2)-plasma treatment.展开更多
基金financially supported by the National Science and Technology Major Project of China (No. 2013ZX02303-001-002)。
文摘The effect of N_(2)-plasma-treated SiO_(2) interfacial layer on the interfacial and electrical characteristics of HfO_(2)/SiO_(2)/p-Si stacks grown by atomic layer deposition(ALD) was investigated.The microstructure and interfacial chemical bonding configuration of the HfO_(2)/SiO_(2)/Si stacks were also examined by high-resolution transmission electron microscopy(HRTEM) and X-ray photoelectron spectroscopy(XPS).Compared with the samples without N2-plasma treatment,it is found that the samples with N2-plasma treatment have less oxygen vacancy density for SiO_(2) interfacial layer and better HfO_(2)/SiO_(2) interface.In agreement with XPS analyses,electrical measurements of the samples with N2-plasma treatment show better interfacial quality,including lower interface-state density(Dit,9.3 × 1011 cm^(-2)·eV^(-1) near midgap) and lower oxidecharge density(Q_(ox),2.5 × 1012 cm^(-2)),than those of the samples without N_(2)-plasma treatment.Additionally,the samples with N_(2)-plasma treatment have better electrical performances,including higher saturation capacitance density(1.49 μF·cm^(-2)) and lower leakage current density(3.2 × 10^(-6) A·cm^(-2) at V_(g)=V_(fb)-1 V).Furthermore,constant voltage stress was applied on the gate electrode to investigate the reliability of these samples.It shows that the samples with N_(2)-plasma treatment have better electrical stability than the samples without N_(2)-plasma treatment.