Effect on passivation mechanism and properties of HfO2/crystalline-Si interface under different annealing atmosphere

Influence of co-reactants on surface passivation by nanoscale hafnium oxide layers grown by atomic layer deposition on silicon

“…6(a), yields some insight. For each film type, the highest passivation quality is generally achieved with annealing in an air environment (consistent with both our prior work 6 and recent reports 13,49 ), although for O 2 –HfO x similar passivation quality is achieved for air as for a forming gas environment. For all co-reactants, similar passivation is obtained when annealing in either an O 2 or N 2 environment (lower than that obtained with annealing in an air environment), consistent with our prior work on O 2 –HfO x .…”

Effect of films thickness and hydrogen annealing on passivation performance of plasma ALD based Hafnium oxide films

“…A passivation layer of HfO x with less than 5 nm thickness is sufficient in thermal ALD to achieve improved passivation [23,24]. However, the use of a thick HfO x passivation layer is necessary to achieve better minority carrier lifetime, particularly in the case of PALD [25][26][27]. These findings support the idea that the choice of ALD method and the thickness of the HfO x layer play crucial roles in optimizing passivation performance in photovoltaic applications [28,29].…”

“…Poor surface passivation quality was achieved for AD films which may be attributed to increased surface defect states originating from the interaction between plasma species and the surface sites [15]. Thus, a post-deposition annealing step seems inevitable for improving the silicon surface passivation quality of HfO x films deposited using the PALD technique [27]. In the present work, the thin films were annealed in a vertical tube furnace, in H 2 ambient in steps of 15 min, i.e., after every 15 min of annealing, the samples were cooled, taken out for τ eff measurements, and again inserted in the tube furnace for the next 15 min of annealing.…”

“…W. Ailish et al demonstrated 12 nm thick HfO x films deposited on n-Si with a minimum SRV value of 4.1 cm s −1 [34]. Xiao et al investigated the impacts of post-deposition annealing on passivation qualities on n-Si by HfO 2 thin films providing the highest effective lifetime of 290 μs after annealing in air [27]. Therefore, post-deposition annealing has an important role in realising good quality surface passivation by plasma ALD based HfO x e films.…”

Effect of high temperature annealing on cryogenic transport properties of silicon MOSFETs with a thin SiO2/HfO2 stacked dielectric

“…The annealing conditions, such as annealing atmosphere, annealing time and annealing temperature, have an important influence on the defects and interface state. The annealing atmosphere affects the dielectric regrowth process [27]. The silicon oxide will regrow in the oxygen-containing atmosphere while silicon atoms will diffuse into HfO 2 to form silicates in the oxygen-deficient atmosphere [28].…”