0000000000189926
AUTHOR
M. Vulpio
showing 7 related works from this author
Nanocrystal metal-oxide-semiconductor memories obtained by chemical vapor deposition of Si nanocrystals
2002
We have realized nanocrystal memories by using silicon quantum dots embedded in silicon dioxide. The Si dots with the size of few nanometers have been obtained by chemical vapor deposition on very thin tunnel oxides and subsequently coated with a deposited SiO2 control dielectric. A range of temperatures in which we can adequately control a nucleation process, that gives rise to nanocrystal densities of ∼3×1011 cm−2 with good uniformity on the wafer, has been defined. The memory effects are observed in metal-oxide-semiconductor capacitors or field effect transistors by significant and reversible flat band or threshold voltage shifts between written and erased states that can be achieved by …
Nanocrystal MOS with silicon-rich oxide
2001
By electrical measurements we investigate the charge trapping and the charge transport in MOS capacitors in which the gate oxide has been replaced with a silicon rich oxide (SRO) film sandwiched between two thin SiO2 layers.
Memory effects in MOS capacitors with silicon rich oxide insulators
2000
ABSTRACTTo form crystalline Si dots embedded in SiO2, we have deposited thin films of silicon rich oxide (SRO) by plasma-enhanced chemical vapor deposition of SiH4 and O2. Then the materials wereannealed in N2 ambient at temperatures between 950 and 1100 °C. Under such processing, the supersaturation of Si in the amorphous SRO film produces the formation of crystalline Si dots embedded in SiO2. The narrow dot size distributions, analyzed by transmission electron microscopy, are characterized by average grain radii and standard deviations down to about 1 nm. The memory function of such structures has been investigated in metal-oxidesemiconductor (MOS) capacitors with a SRO film sandwiched be…
Memory effects in MOS capacitors with silicon quantum dots
2001
To form crystalline Si dots embedded in SiO2, we have deposited thin films of silicon-rich oxide (SRO) by plasma-enhanced chemical vapor deposition of SiH4 and O2. Then the materials have been annealed in N2 ambient at temperatures between 950°C and 1100°C. Under such processing, the supersaturation of Si in the amorphous SRO film produces the formation of crystalline Si dots embedded in SiO2. The narrow dot size distributions, analyzed by transmission electron microscopy, are characterized by average grain radii and standard deviations down to about 1 nm. The memory functions of such structures has been investigated in MOS capacitors with a SRO film sandwiched between two thin SiO2 layers …
Electrical and structural characterization of metal-oxide-semiconductor capacitors with silicon rich oxide
2001
Metal-oxide-semiconductor capacitors in which the gate oxide has been replaced with a silicon rich oxide (SRO) film sandwiched between two thin SiO2 layers are presented and investigated by transmission electron microscopy and electrical measurements. The grain size distribution and the amount of crystallized silicon remaining in SRO after annealing have been studied by transmission electron microscopy, whereas the charge trapping and the charge transport through the dots in the SRO layer have been extensively investigated by electrical measurements. Furthermore, a model, which explains the electrical behavior of such SRO capacitors, is presented and discussed. © 2001 American Institute of …
Memory effects in single-electron nanostructures
2001
We investigate the memory function at room temperature in devices based on quantum dots. By Low Pressure Chemical Vapour Deposition (LPCVD) we deposited Si dots embedded in SiO2. On these devices flat band voltage shifts were well detected at low write voltages for write times of the order of milliseconds, and furthermore, a plateau in the flat band voltage shift, maybe consequence of Coulomb blockdale, was observed.
Nanocrystal MOS memories obtained by LPCVD deposition of Si nanograins
2001
We have realized silicon quantum dots embedded in SiO2 which act as nano-floating gates of MOS memories. The dots with nanometer sizes have been deposited by LPCVD on a 3nm tunnel oxide. Two processes at a fixed pressure have been explored by varying the temperature. SiH4 with a N2 carrier gas have been used in the former case, SiH4 and H2 have been used in the latter. In both cases a nanocrystalline silicon layer is obtained, with nanocrystals a density higher than 1011 cm-2. The process with H2 carrier gas is more controllable and leads to the formation of nanocrystals with a more regular shape. In both cases the density of grains is able to originate detectable threshold shifts in the me…