Pulsed ion-beam induced nucleation and growth of Ge nanocrystals on SiO2

Abstract

Pulsed low-energy (200eV) ion-beam induced nucleation during Ge deposition on thin SiO2 film was used to form dense homogeneous arrays of Ge nanocrystals. The ion-beam action is shown to stimulate the nucleation of Ge nanocrystals when being applied after thin Ge layer deposition. Temperature and flux variation was used to optimize the nanocrystal size and array density required for memory device. Kinetic Monte Carlo simulation shows that ion impacts open an additional channel of atom displacement from a nanocrystal onto SiO2 surface. This results both in a decrease in the average nanocrystal size and in an increase in nanocrystal density.

Ge‐doping dependence of gamma‐ray induced germanium lone pair centers in Ge‐doped silica

“…In addition SiO 2 samples with embedded Ge nanocrystal (nc-Ge) often have an emission at ~ 3.2 eV [6][7][8][9]. This type of material is believed to be promising for micro and opto electronic applications [10][11][12] and many investigations suggest that the 3.2 eV emission is originated by a process of electron-hole recombination involving the Ge oxygen deficient defects. In particular, the GLPC that are located at the interface layers between ncGe and SiO 2 produced during the preparation of the materials seem to be involved [6][7][8][9].…”

Spectro-ellipsometric modeling and optimization of two-dimensional Ge layer and three-dimensional Ge dot/island structures on SiO2 substrates

“…In-situ SE has previously been used to monitor Ge epitaxy and Ge island growth on Si(100) and Si(111) surfaces. [1][2][3][4][5][6][7][8] Formation of Ge islands/dots on SiO 2 has been a major topic, [9][10][11][12][13][14][15][16][17][18][19][20] considering that the Ge/SiO 2 system can be applied to various opto-electronic devices including singleelectron transistors, floating-gate memories, and light emitters. While in situ SE study on nucleation and growth of Si on SiO 2 was reported by Basa et al, 21) there have been very few SE-based experiments on Ge growth on SiO 2 .…”

Oxygen partial pressure dependence of memory effect of sputtered nc-Al/α-Al2O3 thin films

“…Nanocrystals embedded in a dielectric matrix thin films, such as nc-Ge/SiO 2 [1], nc-Si/SiO 2 [2,3] and nc-Al/AlN [4], have attracted growing attention as a promising candidate for charging nodes in a single-electron memory device (SEMD). Compared to continuous floating gate, the nanofloating gate memory shows an advantage of improved endurance due to preventing lateral charge movement.…”