Evaluation of electron traps in SiN_x by discharge current transient spectroscopy: verification of validity by comparing with conventional DLTS

Abstract

Discharge current transient spectroscopy (DCTS) is a promising technique for detecting the trap level and density in dielectrics because it is based on a simple emission process. In order to confirm the validity of DCTS, we compare the results from the conventional deep-level transient spectroscopy (DLTS) technique for samples of CVD-grown silicon nitride (SiNx) films. Results indicated that a trap level, about 0.6 eV below the energy level of the conduction band edge in the SiNx thin films estimated by DCTS is in good agreement with that obtained from DLTS analysis, and it is found that the trap density increases with the decreasing N/Si ratio in the SiNx film. As a proposed estimation for energy level in defects, it will be originated from hydrogen-incorporated defects in the SiNx matrix. This study demonstrates that the DCTS method will be a useful electrical method for the evaluation of defects.

Impact of hydrogen plasma treatment on fluorine-contained silicon nitride films

“…Next, to investigate the influence of the hydrogen plasma treatment on the trap energy level contributing the hole trapping further, the discharging current transient spectroscopy (DCTS) [28][29][30][31][32][33][34] was utilized to analyze each MIS capacitor. In the DCTS method, a charging voltage is applied to the MIS capacitor and holes are captured in the SiN film.…”

Effects of post‐deposition annealing on chemical composition of SiNx film in SiO2/SiNx/SiO2/Si stacked structure

“…The performances of these devices strongly depend on the SiN x film qualities that are controlled by the deposition and annealing conditions. For instance, the trap density strongly depends on the chemical composition of the SiN x film 3 and the chemical properties and impurity (e.g., N–H and Si–H) densities of SiN x are affected by annealing 4 . Although single‐layer SiN x has been widely studied over the past decades, previous work on the effects of annealing on the properties of SiN x films within multi‐layer stacked structures is insufficient.…”

A high-precision current measurement platform applied for statistical measurement of discharge current transient spectroscopy of traps in SiN dielectrics

“…[29][30][31] Based on the same concept of the array test circuit for current measurement and the platform for resistance measurement, we developed a current measurement platform that can form DUTs for each unit cell by forming dielectric films on the platform by an additional process with simple steps and measure leakage current of a large number of samples. Discharge current transient spectroscopy (DCTS) [32][33][34][35][36][37][38][39] has been proposed as one of the electrical evaluation methods for the trap property. It has been reported to be a useful method that can easily evaluate energy levels and densities of traps in a dielectric film by measuring the discharge current of capacitors.…”