The effects of nitrogen profile and concentration on negative bias temperature instability of plasma enhanced atomic layer deposition HfOxNy prepared by in situ nitridation

Abstract

Articles you may be interested inDependences of nitrogen incorporation behaviors on the crystallinity and phase distribution of atomic layer deposited Hf-silicate films with various Si concentrations J. Appl. Phys. 104, 054101 (2008) We have prepared plasma enhanced atomic layer deposition HfO x N y thin films by in situ nitridation using nitrogen/oxygen mixture plasma and studied the effects of nitrogen contents and profiles on the negative bias temperature instability ͑NBTI͒. The nitrogen depth profiles and concentrations were controlled by changing the exposure sequences and the nitrogen to oxygen flow ratio, respectively. The best immunity to NBTI degradations was obtained for the nitrogen to oxygen ratio of 2:1 when nitrogen atoms are incorporated away from the high k / Si interface. We propose a dielectric degradation mechanism based on the reaction-diffusion model in which nitrogen plays a role of hydrogen generator at the interface and diffusion barrier in the bulk film.

Improved electrical characteristics of amorphous InGaZnO thin-film transistor with HfLaO gate dielectric by nitrogen incorporation

“…2(d), V th decreases monotonically from 4.08 to 2.85 V with increasing N 2 flow rate from 0 to 16 sccm, owing to the C ox increase and also the nitrogen-induced positive oxide charges. 22,23) The k values of the HfLaO films in Table I are smaller than many reported values because the HfLaO films in this work are not crystalline owing to their low postdeposition annealing temperature (400 °C), which is much lower than others (600-1000 °C). In addition, the oxidation of the Si substrate during the annealing and sputtering can result in a low-k interlayer at the Si=HfLaO interface, thus further decreasing the k value.…”

“…2(c)] 17) and a large number of positive fixed oxide charges in dielectrics. 22,23) Therefore, carrier scattering could be enhanced, as revealed by the deterioration of μ sat , I on , and I on =I off for N 2 flow rates higher than 4 sccm in this work.…”

Plasma-Assisted Atomic Layer Deposition: Basics, Opportunities, and Challenges

“…138,318 It is, for example, relatively straightforward to incorporate N atoms into oxide thin films by the addition of N 2 to a plasma generated in O 2 . 38,73,128,134,143,146,319 Such controlled doping of thin film materials is difficult to achieve with strictly thermally-driven ALD reactions.…”

Flatband voltage control in p-metal gate metal-oxide-semiconductor field effect transistor by insertion of TiO2 layer

“…The extraction of capacitance equivalent thickness ͑CET͒ values and interface state density ͑D it ͒ is described in our previous reports. 12,13 Figure 1͑a͒ shows XPS spectra in Al 2p binding energy region for as-deposited and HTA ͑T a = 800°C͒ HfO 2 samples with Al 2 O 3 top layer ͑Si/ HfO 2 / Al 2 O 3 ͒. For both samples, Al 2p peak is observed clearly at 75 eV, indicating the presence of Al 2 O 3 top layer.…”