Metallic nano-crystals for flash memories

Dufourcq, J.; Mur, P.; Gordon, Michael J.; Minoret, S.; Coppard, R.; Baron, T.

doi:10.1016/j.msec.2006.09.037

Cited by 32 publications

(28 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[3][4][5] In particular, applications to nonvolatile memory have been widely studied. [6][7][8] In addition, the melting temperature of nanoclusters decreases. 9 These properties are strongly dependent on the high surface-to-volume ratio, the atomic and electronic arrangement characters, and the size of the nanoclusters.…”

Section: Introductionmentioning

confidence: 99%

<I>In-Situ</I> Electrical Conductivity Measurement of Oxidation of Tin Nanocluster Film

Kang

Lee²,

Yoo³

et al. 2012

j. nanosci. nanotech.

View full text Add to dashboard Cite

An in-situ electrical conductivity measurement of thin films of tin oxide nanoclusters for nano-devices was performed during metal cluster deposition and subsequent oxidation. From the current observation, the percolation threshold and the oxidation process are suggested. During baking at 200 degrees C, tin nanoclusters were transformed into low-conductivity stannous oxide and then into high-conductivity stannic oxide. From electron micrographs, it is suggested that the baking procedure is responsible for changing the oxide state and/or the crystallinity of the individual nanoclusters rather than changing the morphology of the film.

show abstract

Section: Introductionmentioning

confidence: 99%

<I>In-Situ</I> Electrical Conductivity Measurement of Oxidation of Tin Nanocluster Film

Kang

Lee²,

Yoo³

et al. 2012

j. nanosci. nanotech.

View full text Add to dashboard Cite

show abstract

“…11,12 However, memory devices with such low nanocrystal densities have been reported earlier. 11,23,24 The subsequent postdeposition annealing ͑PDA͒ in N 2 results in the increase of crystallite sizes and improvement of crystalline quality of the nanocrystals. During PDA treatment, Ni-NCs diffuse into the tunneling oxide layer, resulting in a decrease of tunneling oxide thickness to ϳ5 nm from the initial one.…”

mentioning

confidence: 99%

Memory Characteristics of Nickel Nanocrystals with High-k Dielectric Tunneling Barriers

Panda

Maikap

Dhar

et al. 2009

Electrochem. Solid-State Lett.

View full text Add to dashboard Cite

The structural and electrical characteristics of Ni nanocrystals embedded in high-k HfO 2 have been studied. High-resolution transmission electron microscopy revealed the formation of tiny Ni nanocrystals, in the average diameter of ϳ8 nm size for the sample annealed at 1000°C for 5 min. Atomic force microscopy shows the deposition of uniform Ni nanocrystals on a HfO 2 layer. A good hysteresis memory window of ϳ2.1 V at sweeping gate voltage of Ϯ15 V was observed in optimized annealed samples. A maximum flatband voltage shift of 2.1 Ϯ 0.05 V was accomplished for the optimized sample. The retention and leakage current of the metal oxide semiconductor capacitors were also studied.Floating gate memory structures based on charge storage in discrete semiconductor and metal nanocrystals ͑NCs͒ have recently attracted renewed interest for their potential applications in nextgeneration flash memory devices. 1-14 Embedded NCs in the floating gate sandwiched between tunnel and control oxide layers are charged by direct-tunnel electrons from the channel to shift the device threshold.The downscaling of tunnel oxide thickness leads to reduction in operation voltage to attain faster programming and erasing speeds. Current efforts are focused on replacing conventional SiO 2 in the flash memory gate stack with high-dielectric-constant ͑high-k͒ materials 2,3,8,11,15,16 to remove the limitation of scaling trend in controlling the gate tunnel current for flash memory devices and to enhance retention performance. Most of the studies, including ours, have focused on the fabrication of metal-oxide-semiconductor ͑MOS͒ structures having semiconductor NCs. 5-8 Nevertheless, MOS-based memory devices fabricated with metal NCs, like Au, 9 Ni,[9][10][11] Ru, 12 W, 13 Pd, 14 RuO x , 17 TiN, 18 etc., are considered to be more advantageous for their higher density of states around the Fermi level, a wide range of available work function, stronger coupling with conduction channels, and smaller energy perturbation due to carrier confinement, 19-22 with the semiconductor counterpart. The use of metal NCs also makes it possible to use smaller operating voltages while obtaining better endurance characteristics and faster write/erase speeds with smaller fluctuations and interface states due to its high work function in comparison to its semiconductor counterpart. 19,20 Among other metals, nickel, which is attractive for complementary MOS technology as metal gate electrodes 21 and source drain engineered devices, 22 has not been fully explored for nonvolatile memories. Due to their high work function ͑ϳ4.9 eV͒, Ni NCs result in deep quantum wells for the trapping of charge carriers. Most of the work based on Ni NCs has been performed using conventional silicon dioxide as a tunneling barrier.In this article, we report the electrical characteristics of Ni NC MOS structures using HfO 2 as tunneling and control dielectrics. The effect of postdeposition annealing on memory and the structural, interfacial, and electrical properties of the floating gate memo...

show abstract

“…[1][2][3][4] Many materials, such as Si, Ge, Ni, and Co, have been proposed to fabricate nanocrystal memory. [2][3][4][5][6] Because of benefits on strong coupling, deep quantum well, and large density of state, metal nanocrystals have recently received much attention for research. [5][6][7] However, the use of metal must take thermal stability issue into account because the metal diffusion into or chemical reaction with tunnel oxide during the memory fabrication process will compromise the performance of the memory structure.…”

mentioning

confidence: 99%

“…[2][3][4][5][6] Because of benefits on strong coupling, deep quantum well, and large density of state, metal nanocrystals have recently received much attention for research. [5][6][7] However, the use of metal must take thermal stability issue into account because the metal diffusion into or chemical reaction with tunnel oxide during the memory fabrication process will compromise the performance of the memory structure. 6 Mo is an attractive candidate because of its high work function, compatible with complementary metal-oxide-semiconductor process and high thermal stability.…”

mentioning

confidence: 99%

“…[5][6][7] However, the use of metal must take thermal stability issue into account because the metal diffusion into or chemical reaction with tunnel oxide during the memory fabrication process will compromise the performance of the memory structure. 6 Mo is an attractive candidate because of its high work function, compatible with complementary metal-oxide-semiconductor process and high thermal stability. 8 In this study, nonvolatile memory characteristics of Mo nanocrystals embedded in SiO x were investigated by thermal annealing oxygen incorporated Mo silicide layer.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Charge storage characteristics of Mo nanocrystal dependence on Mo oxide reduction

Lin

Chang

et al. 2008

Appl. Phys. Lett.

View full text Add to dashboard Cite

Metallic nano-crystals for flash memories

Cited by 32 publications

References 9 publications

<I>In-Situ</I> Electrical Conductivity Measurement of Oxidation of Tin Nanocluster Film

<I>In-Situ</I> Electrical Conductivity Measurement of Oxidation of Tin Nanocluster Film

Memory Characteristics of Nickel Nanocrystals with High-k Dielectric Tunneling Barriers

Charge storage characteristics of Mo nanocrystal dependence on Mo oxide reduction

Contact Info

Product

Resources

About