5 research outputs found
Recommended from our members
Verbundprojekt: Effiziente, kostengünstige InGaN-Lichtquellen auf Silizium-Substraten für die Allgemeinbeleuchtung, Teilvorhaben: Elektronenmikroskopische Charakterisierung und Modellierung von Versetzungsprozessen von InGaN-Lichtquellen auf Si-Substraten : Schlussbericht ; Laufzeit des Vorhabens: 01.02.2009 - 31.01.2012
[no abstract available
Unraveling the atomic mechanism of the disorder–order phase transition from γ-Ga2O3 to β-Ga2O3
Defect generation by nitrogen during pulsed sputter deposition of GaN
Pulsed sputter deposition has been demonstrated to be a viable process for the growth of high quality GaN and InGaN/GaN LEDs. It enables the fabrication of nitride LEDs with a red emission wavelength at large areas. In this study, we explore details on the epitaxial sputter deposition of GaN with a particular emphasis on ion damage. By changing the argon to nitrogen ratio, we adjust
the growth mode from island to layer growth. TEM revealed speckles in the epitaxial GaN, which could be identified as isolated basal stacking faults, acting as non-radiative recombination centers. Using Monte Carlo methods, we modeled the energies of backscattered and sputtered atoms in order to get information on the ion damage mechanisms. Considering the collisions on the way from the target to the substrate, we found energetic nitrogen to induce the speckles. A shielding mechanism based on metallic gallium has been identified, leading to the strongly increased luminescence quality in comparison to the non-shielded material