Characterization of PVD Lumogen films for wavelength conversion applications

Abstract

Lumogen Yellow S0790 is a commercial azomethine based pigment and is used for enhancing CCD devices for detecting ultraviolet radiation. In this work we report on the crystal structure and morphology of the raw material, as-deposited and post-annealed films, as well as the influence these have on the subsequent optical properties. Our measurements of physical vapour deposited (PVD) Lumogen films indicate that commercial Lumogen powder is crystalline in its as-received state, with a melting point of 273.3°C and boiling point of 328.6°C. Furthermore, we have found that as-deposited films on room temperature substrates possess an inherent crystalline structure, which has not been reported previously, but also that the material's structure changes into a completely different crystalline form upon annealing for 90 hours at 80°C.

The research of ultraviolet detection by using CCD

“…Under a normal condition, Lumogen Yellow S 0790 is a kind of yellow powder, which is nontoxic and not dissolve in water or alcohol, and it is been proved that it has stable chemical properties in previously research. The chemical structure of Lumogen, or 2-hydroxy-[(2-hydroxy-1-naphthalenyl) methylene] hydrazone [1] , which comprises an hydroxyl terminated naphthalene group attached to each end of an azomethine chain, is shown in figure 1. Employment of a thin, translucent Lumogen film on the front side of the CCD enhances the UV response of the device, but a small penalty is paid in the visible region due to attenuation by the overlayer film.…”

Grazing incidence X-ray studies of ultra-thin Lumogen films

“…Furthermore, Lumogen has been used on the imaging CCD systems of the Hubble Space telescope and the Cassini space probe [6]. However, problems encountered in the production of Lumogen Ò coated CCDs for the Cassini spacecraft as highlighted in a Jet Propulsion Laboratory Report [7] indicated an instability in the crystalline structure of the as-deposited Lumogen Ò film, was originally suggested much earlier in a study by Kristianpoller and Dutton [8] and has been the focus of our work in this area [9,10].…”

Polarization‐Sensitive Ultraviolet Detection from Oriented‐CdSe@CdS‐Dot‐in‐Rods‐Integrated Silicon Photodetector

“…The incorporation of luminescent downshifting materials, such as fluorescent dyes, rare‐earth doped compounds, and colloidal quantum dots (QDs), with charge‐coupled devices (CCDs) or complementary metal oxide semiconductors (CMOS) provides a low‐cost route to fabricating UV photodetectors . Among them, colloidal QDs show advantageous properties of strong UV absorption, tunable photoluminescence (PL) emission, high quantum yields (QYs), and straightforward solution processability, which have been successfully applied to enhance the UV response of Si photodetectors and solar cells .…”