Atomic layer deposition of HfN_x films and improving the film performance by annealing under NH₃ atmosphere

Abstract

Flowchart illustrating how the films are deposited (a) without and (b) with cleaning step, and Auger electron spectroscopy depth profile of 15 nm HfNx deposited with precleaning step, before annealing (c) and after 900 °C annealing at NH3 atmosphere.

Impact of operation voltage and NH3 annealing on the fatigue characteristics of ferroelectric AlScN thin films grown by sputtering

“…After NH 3 annealing, the oxygen concentration inside the AlScN film decreased from 3.5 to 2.3%, and the amount of oxygen at the interface between TiN and AlScN also decreased, as previously reported. 23 As described below, such a decrease in the oxygen impurity concentration improves the FE switching performance.…”

“…In this regard, the previous report by Ryoo et al , where the oxygen impurity and nitrogen vacancy in the HfN film could be removed by annealing in an NH 3 environment, is notable. 23 Therefore, AlScN capacitors were annealed under the NH 3 environment to lower the fatigue rate at temperatures 500, 700, and 900 °C for 30 s. Before investigating the effect of NH 3 annealing on the electrical properties, the structure and chemical properties of the AlScN were analyzed following the NH 3 annealing.…”

“…The previous work indicated that the amount of impurity within nitride material could be decreased by NH 3 annealing. 23 Therefore, NH 3 annealing may also lead to a reduction in the fatigue rate of AlScN. It was confirmed that the fatigue rate decreased after NH 3 annealing, which can be attributed to the decreased oxygen concentration in AlScN.…”

Tailoring thin film transistor performance through plasma reactant manipulation in indium oxynitride films

“…The incorporation of oxygen can result from the chemical reaction-based deposition step, which leads to the formation of metal-oxygen bonds even in a low-oxygen environment during ALD. 26 We also compared the composition of InON samples fabricated under the same plasma power (100 W) in Table S1 (ESI†) to exclude the influence of the plasma power on the film composition, because the optimized ALD process of the two reactants is different (200 W for N 2 and 50 W for NH 3 plasma). At the same plasma power, the sample fabricated using NH 3 plasma exhibited higher nitrogen content of 24.9 at%, compared to 18.9 at% in the N 2 -fabricated sample, and lower oxygen content of 21.0 at%, compared to 32.4 at% in the N 2 -fabricated sample.…”