Fowler–Nordheim current injection and write/erase characteristics of metal–oxide–nitride–oxide–Si structure grown with helicon-wave excited plasma processing

Abstract

Metal–oxide nitride–oxide–Si (MONOS) structure was fabricated using the oxidation-nitridation series with helicon-wave O2–Ar and N2–Ar plasmas, respectively. The detrimental effect of Ar ion etching was minimized during the fabrication process by controlling the plasma–sheath width. The top oxide was very thin (∼1–2 nm) as compared with nitride (∼12–13 nm) and bottom oxide (∼7–8 nm). Fowler–Nordheim tunneling electron injection was performed in this MONOS diode for both dc and pulsed stress voltages with the electrical polarity being changed. For the positive stress voltage, the shift of the threshold voltage Vth was negative and larger for the smaller stress voltage. It was higher for the pulsed stress than for the dc one. On the other hand, Vth shift is positive and smaller for the pulsed stress than for the dc one for the negative stress bias. These findings can almost be explained by the avalanche breakdown model together with the effect of the total amount of the injected carries. Terman analysis indicated that the interface state density did not increase after both positive and negative stresses, which was probably due to film structure and the presence of a small amount of Si oxynitride (or Si–N–O bonds) at the insulator/Si interface. Write/erase characteristics were also briefly discussed.

Thrust Measurements of a Radio Frequency Plasma Source

“…Although there are several uses for helicon plasmas in terrestrial applications, such as plasma processing [7], there have also been studies considering helicon sources in space propulsion. Some research considers using the helicon source as an ion generator [8][9][10][11]; other work examines the possibility of the helicon source itself as a thruster [12][13][14][15].…”

Thrust Measurements of a Helicon Plasma Source

“…15 Therefore the center of the first peak corresponds to the plasma potential, and only ions past that energy are accelerated. From the data in Figure 10, the average ion exit velocity can be calculated using the equation (7) where x j is the probability at each voltage, V j is the voltage of the j th term of the series, V p is the plasma potential, and m i is the mass of the ion. Figure 11 shows the estimated average ion exit velocity.…”

“…4 The high efficiency of the helicon source was previously attributed to Landau damping 1 but later work has considered Trivelpiece-Gould (TG) wave coupling as the primary mechanism. 5,6 While there are several uses for helicon plasmas in terrestrial applications, such plasma processing, 7 there has also been studies considering helicon sources in space propulsion. While some research considers using the helicon source as an ion generator, [8][9][10][11] other work examines the possibility of the helicon source itself as a thruster.…”

Static states and dynamic behaviour of charges: observation and control by scanning probe microscopy

“…Using SNDM, Cho et al successfully visualized the remaining charges in a gate film after writing-erasing cyclic sequences of metal-(SiO 2 -Si 3 N 4 -SiO 2 )-semiconductor (metal-ONO-semiconductor, MONOS)-type flash memory [51]. In the MONOS memory, the electrons injected in the write process must be completely neutralized by holes supplied during the erasing process.…”