In this work. we show the fabrication of colloidal nanocrystals (NCs) based waveguide photonic devices by exploiting a new lithographic approach for the nano-positioning of NCs. Our approach relies on the dispersion of CdSe/ZnS core/shell NCs into a layer of electro-sensitive resist (poly-methyl methacrylate, PMMA), which is subsequently patterned by means of electron beam lithography (EBL). This localization technique has been demonstrated by detecting high-resolution photoluminescence (PL) maps on an e-beam nano-pattemed PMMA/NCs film through a confocal microscope. This technique has been exploited for the fabrication of distributed feedback (DFB) structures and distributed Bragg reflectors (DBR) suitable for the realization of in-plane waveguide lasers. A DFB structure has been obtained by patterning a periodical grating on a PMMA/NCs ridge waveguide. Two DBR have been similarly fabricated by creating quarter-wavelength thick alternated stripes of air and active blend; these structures have been exploited as front and back mirrors of an in-plane PMMA/NCs ridge cavity. In both cases, no following etching processes have been required. thus simplifying the steps needed for the fabrication of NCs based active photonic devices. (C) 2006 Elsevier B.V. All rights reserved.
Lithographic nano-patterning of colloidal nanocrystal emitters for the fabrication of waveguide photonic devices
Carbone L;De Vittorio M
2007
Abstract
In this work. we show the fabrication of colloidal nanocrystals (NCs) based waveguide photonic devices by exploiting a new lithographic approach for the nano-positioning of NCs. Our approach relies on the dispersion of CdSe/ZnS core/shell NCs into a layer of electro-sensitive resist (poly-methyl methacrylate, PMMA), which is subsequently patterned by means of electron beam lithography (EBL). This localization technique has been demonstrated by detecting high-resolution photoluminescence (PL) maps on an e-beam nano-pattemed PMMA/NCs film through a confocal microscope. This technique has been exploited for the fabrication of distributed feedback (DFB) structures and distributed Bragg reflectors (DBR) suitable for the realization of in-plane waveguide lasers. A DFB structure has been obtained by patterning a periodical grating on a PMMA/NCs ridge waveguide. Two DBR have been similarly fabricated by creating quarter-wavelength thick alternated stripes of air and active blend; these structures have been exploited as front and back mirrors of an in-plane PMMA/NCs ridge cavity. In both cases, no following etching processes have been required. thus simplifying the steps needed for the fabrication of NCs based active photonic devices. (C) 2006 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.