New Recording Layer of Recordable Digital Versatile Disc with CrO_x Film Using Red Laser

Abstract

In this study, CrOx film deposited by rf magnetron reactive sputtering was used as a new recording layer for a recordable digital versatile disc (DVD-R) with a red laser. X-ray photoelectron spectroscopy (XPS) indicated the films have three major components: CrO2, CrO3, and Cr2O3. From disc dynamic tests and atomic force microscope (AFM) images of a polycarbonate (PC) substrate, a DVD-R structure of PC/ZnS–SiO2 (30 nm)/CrOx (120 nm)/ZnS–SiO2 (40 nm)/Ag (50 nm), deposited by sputtering at an O2/Ar flow rate ratio of 0.4, had an improved carrier-to-noise ratio (CNR). The principle of recording depends primarily on the explosive pressure of the O2 released due to laser heating of the annealed CrOx film.

Feasibility Study of ZnO/Ge Bilayer Recording Medium in Blue Laser Recordable Disc

“…Due to the close correlation between the properties of the recording and dielectric layers of the disc, such as their optical and thermal properties, it is necessary to choose suitable thickness for each layer, including the dielectric film and ZnO/Ge bilayer film, to analyze the performance of the disc. According to our previous studies, 4,5) better optical and thermal properties could be obtained by selecting the thicknesses of dielectric layer I, dielectric layer II, and the reflecting layer to be 30, 20, and 120 nm, respectively. According to the disc structure we proposed, a laser beam is first introduced into the ZnO layer and then goes through the Ge layer.…”

“…In the past few years, organic recording materials have been widely used in recordable compact disc (CD-R) and digital versatile disc recordable (DVD-R) discs. [1][2][3][4][5] Owing to the high recording sensitivity of the organic recording material, the laser pulse power was low as data was written into the disc. However, the low recording sensitivity of organic materials due to their low absorptance in the blue laser region is a major problem.…”