Effects of thermal annealing on charge density and N chemical states in HfSiON films

Abstract

Band offsets and chemical bonding states in N-plasma-treated HfSiON gate stacks studied by photoelectron spectroscopy and x-ray absorption spectroscopy

Band bending analysis of charge characteristics at GeO2/Ge interface by x-ray photoemission spectroscopy

“…This result is also consistent with our previous tail states emerged in APO-GeO 2 interface investigated by internal photoemission spectroscopy, which is also attributed to the oxygen-deficient related bulk defects [45]. Furthermore, previous investigations suggest two approaches including the current flowing from the samples to the ground, that is, the sample current, and Poisson equation with the measurement of band bending from the semiconducting substrate at the dielectrics/semiconductor interface (Ge 3d 0 in our case) [29][30][31] can be used to quantitatively calculate the net hole and electron traps during time-dependent XPS measurements. However, as discussed above, we confirm an insignificant impact of charges cinside of the GeO 2 on the Ge band bending under the x-ray irradiation, implying the charges might distribute mainly along the GeO 2 surface and/or the density is quite low.…”

“…Compared with commonly used capacitance-voltage (C-V) and conductance method including surface potential fluctuation to investigate the nature of interface traps at GeO 2 /Ge interface [19], x-ray photoemission spectroscopy (XPS) offers another simple nondestructive tool to examine various interface/ bulk charged defects by monitoring semiconductor surface potential variation (band bending) at semiconductor/insulator interface with a variable probing depth. No metal electrode usage in XPS measurement validly avoids possible interaction between metal and dielectrics in metal/GeO 2 /Ge capacitors used for C-V and conductance methods, which enables its widely usage to characterize the various di electrics/Si interface [29][30][31].…”

Hetero-epitaxial growth of the cubic single crystalline HfO2 film as high k materials by pulsed laser ablation

“…The leakage current of the annealed sample is 5 Â 10 À 6 A/cm 2 at À 1 V (corresponding to a field of 1.4 MV/cm) and exhibits a leakage current reduction of six orders of magnitude compared with these samples without annealing. Since the interface layer thickness has not been found to change much after high temperature annealing, this improvement in leakage current may be due to the enhanced phonon-energy coupling [12] and passivation of interfacial bonds [13]. Moreover, this SiO 2 interfacial layer has not significantly affected capacitance density of the gate stack from which dielectric constant is derived and is close to the theoretically predicted value of 30 for cubic HfO 2 .…”

(Invited) Synchrotron Radiation Photoelectron Spectroscopy of Metal Gate/HfSiO(N)/SiO(N)/Si Stack Structures

“…Figure 7 Then, we attempted to eliminate these trap defects by annealing under controlled atmosphere with oxygen partial pressure. Figure 8(a) shows the annealing oxygen pressure dependence of the binding energy of the Si 2p 3/2 bulk components as a function of the x-ray irradiation time (15). It should be noted that the number of negative fixed charges in the HfSiON films decreases by annealing samples at the low oxygen partial pressure, although electron trap density remains almost unchanged, because the net amount of binding energy shift due to SR irradiation does not change.…”