Size distribution and electroluminescence of self-assembled Ge dots

Abstract

In this article we study the electroluminescence of p-i-n diode structures with Ge dots consisting of coherent three-dimensional small ͑pyramids͒ and larger ͑dome͒ islands. The Ge dots are formed through strain-induced islanding. The diode structures, including one layer with Ge dots, were deposited on Si mesas with variable areas in order to study the influence of limited area deposition on self-assembling. It was observed that the reduction of deposited area improves island uniformity. The combined analysis of island distribution and electroluminescence spectra has lead to the conclusion that domes in small diodes have a smaller Si content or are less relaxed than domes in larger diodes. The diodes are found to emit up to room temperature near the optical communication wavelength of 1.3 microns.

Miniband-related 1.4–1.8 μm luminescence of Ge/Si quantum dot superlattices

“…This value is higher than the external efficiency reported for the QD-based Ge/Si LEDs (g = 10 -6 for k = 1.4 lm, Ref. [44]). In Ref.…”

Metal-Catalyst-Free Growth of Silica Nanowires and Carbon Nanotubes Using Ge Nanostructures

“…Atomic force microscopy (AFM) measurements show that this process delivers particle heights between 1.3 and 2.9 nm and a mean particle density of 460 ± 30 particles/µm 2 . 15) Selected wafers were implanted with carbon at a dose of 3×10 16 cm -2 and an energy of 30 keV. For carbon implanted Ge nanoparticles, samples show a lower modal height of 0.7 nm and a lower particle density of 64 ± 18 particles/µm 2 .…”

“…The SiGe islands have heights ranging from 20 to 50 nm 13) and the Ge dots have diameters ranging from 20 to 250 nm and heights ranging from 10 to 25 nm. 14) Then the wafers were implanted with carbon at a dose of 3×10 16 cm -2 and an energy of 30 keV. The wafers were cut into 5×7 mm pieces and dipped in buffered hydrofluoric acid (HF) solution to remove the native oxide.…”

Towards Directed Self-Assembly of Quantum Dot Mesocrystals of Ge/Si Using Focused Ion Beam Patterning

“…(With permission of ASM International.) The circles and the crosses are taken from [14] and [15], respectively.…”

“…[14][15][16] Additional research is driven by a search for pathways to ever smaller and faster electronic devices, as well as silicon integration technology.…”