Light emission and photoluminescence from high-k dielectrics containing Ge nanocrystals

Abstract

A metal/HfAlO/Si light emitting diode with Ge nanocrystals embedded in HfAlO has the visible light emission (610 nm) and the infrared emission (760 nm). The image and Ge content are measured by the transmission electron microscopy and Raman spectroscopy. The photoluminescence of Ge nanocrystals embedded in HfAlO has a peak wavelength at 700 nm, while the peak wavelength at 725 nm is observed for Ge nanocrystals embedded in HfO(2). The difference of it may be due to the larger band gap of HfAlO as compared to HfO(2). (C) 2009 American Vacuum Society. [DOI: 10.1116/1.3025844

One Step Synthesis of Pure Cubic and Monoclinic HfO2 Nanoparticles: Effects of Temperature and Ambient on the Photoluminescent Properties

“…Some recent studies also support the oxygen vacancy related origin, e.g. Ni et al showed that the luminescence properties of hafnia films can be controlled by modifying the concentration of oxygen vacancies introduced into the lattice [20] and more recently, Chang et al demonstrated in a study on HfO 2 thin films that two broad PL bands centered at 4.13 and 3.3eV are associated with the selftrapped excitons due to abundance of oxygen vacancies in their films [21].…”

Optical and electrical properties of undoped and doped Ge nanocrystals

“…MIS structures fabricated on Si with Si/Ge nanocrystals embedded in the dielectric layer [1,27-29] have been widely studied in this regard. A critical challenge for the MIS LED based on nanocrystals embedded in oxide has been the development of a method for efficient carrier injection.…”

Formation and characterization of varied size germanium nanocrystals by electron microscopy, Raman spectroscopy, and photoluminescence

“…The emission wavelengths can also be tuned between 1548 nm and 1905 nm by changing the doping levels [13]. Ge ncs were reported to emit between 563 nm and 1548 nm explained by the quantum confinement effect (QCE) [15][16][17][18][19][20][21]. In addition, many results have been published covering the entire visible and ultraviolet (UV) ranges related to various defects or interface of Ge ncs with matrix [18,[22][23][24][25][26][27].…”