We investigated the characteristics of silicon nitride (SiNx) thin films deposited by remote plasma atomic layer deposition (RPALD) using trisilyamine (TSA) and ammonia (NH3) plasma at low temperatures. Although the process window of SiNx thin films is 150–350 °C, considering the refractive index (RI), SiNx thin films deposited at 250–350 °C were focused on for analyses. All of the SiNx films were nearly stoichiometric, regardless of the deposition temperature. As the deposition temperature increased, the RI increased, while the hydrogen content decreased. The defect density also changed at higher deposition temperatures; as the deposition temperature increased, all of the trap densities increased because of the low‐hydrogen content in the SiNx thin films. The characteristics of the SiNx thin film deposited by RPALD could be controlled to adjust the defect density for charge trap flash memory applications by changing the deposition temperature.

We demonstrate enhanced resistive switching (RS) stability, as measured by distribution, power consumption, and memory window, using different oxygen contents in a Ta oxide (TaOx) layer with a Pt top electrode and a TiN bottom electrode. The stability of the Pt/TaOx/TiN RRAM device increases as the oxygen contents of the TaOx layer increase. When oxygen is introduced during TaOx deposition, conventional bipolar RS (BRS) switches to self‐compliant BRS, and distribution is improved within 200 repeated RS cycles. We investigate the conduction mechanisms for both a low resistance state (LRS) and a high resistance state (HRS). Ohmic conduction in the LRS and for the low bias region in the HRS corresponds to the conductive filament (CF) theory, while Poole–Frenkel (PF) conduction in the high bias region of HRS is the dominant conduction mechanism. A possible RS mechanism with oxygen ion drift is discussed.

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Phone: þ82 2 2220 0387, Fax: þ82 2 2292 3523We investigated the effects of NH 3 plasma power on characteristics of low-temperature silicon nitride thin films for application of a gate spacer. SiN x thin film was deposited on a Si(100) substrate by remote plasma atomic layer deposition (RPALD) using trisilylamine (TSA) as a Si precursor and NH 3 gas as a reactant. NH 3 remote plasma was analyzed with optical emission spectroscopy (OES) and it largely consisted of NH and H. As the plasma power increased, more NH and H radicals were generated and a proportion of NH radicals in the plasma increased, which resulted in the slight increase of the high-N content and low-H content in SiN x thin film. The low-H content with nearly stoichiometric SiN x thin films improve etch rate properties. The densities of RPALD SiN x thin film were 2.7 g cm À3 and almost the same regardless of plasma power.RPALD SiN x thin films showed a low leakage current density of 10 À7 A cm À2 at 2 MV cm À1 and a breakdown voltage of approximately 8 MV cm À1 .

The silicon nitride (SiNx) atomic layer deposition with bis(dimethylaminomethylsilyl)-trimethylsilyl amine precursor and N2 remote plasma was investigated. The process window ranged from 250 to 400 °C, and the growth rate was about 0.38 ± 0.02 Å/cycle. The physical, chemical, and electrical characteristics of the SiNx thin films were examined as a function of deposition temperature and plasma power. Based on the results of spectroscopic ellipsometry and x-ray photoelectron spectroscopy, the growth rate and state of binding energy showed little difference depending on the plasma power. The better film properties such as leakage current density and etch resistance were obtained at higher deposition temperatures and higher plasma power. High wet etch resistance (wet etch rate of ∼2 nm/min) and low leakage current density (∼10−8 A/cm2) were obtained. The step coverage, examined by transmission electron microscopy, was about 80% on a trench with an aspect ratio of 4.5.