Quantitative study of nitrogen doping effect on cyclability of Ge-Sb-Te phase-change optical disks

Rie Kojima; Takashi Kouzaki; Toshiyuki Matsunaga; Noboru Yamada

doi:10.1117/12.327951

23 October 1998 Quantitative study of nitrogen doping effect on cyclability of Ge-Sb-Te phase-change optical disks

Rie Kojima, Takashi Kouzaki, Toshiyuki Matsunaga, Noboru Yamada

Proceedings Volume 3401, Optical Data Storage '98; (1998) https://doi.org/10.1117/12.327951
Event: Optical Data Storage '98, 1998, Aspen, CO, United States

Abstract

By nitrogen doping into a Ge-Sb-Te phase change optical disk's recording layer, we were able to significantly increase its cyclability. For example, our PD attained, at the maximum, 800,000 overwrite cycles through accurate control of nitrogen concentration. We quantified the nitrogen concentration of recording layer using secondary ion mass spectrometry (SIMS) and determined, from the viewpoint of cyclability, signal amplitude and other parameters, the optimum concentration to be around 2 - 3 at.%. From analyses by thermal desorption mass spectrometry (TDMS) and X-ray diffraction (XD) using powder, we found: (1) nitrogen atoms are mainly bound with Ge to create an amorphous phase of Ge-N; (2) as long as the nitrogen concentration remains around 5 at.%, those Ge, Sb and Te atoms which are not bound with nitrogen form NaCl type crystals. We obtained the following model by combining the results of the above analysis. Nitrogen-doped Ge-Sb-Te recording layer is composed of Ge-Sb-Te grains intermingled with a small quantity of amorphous Ge-N, which exists in the form of a thin film penetrating the grain boundary of Ge-Sb-Te. The Ge-N composing this high-melting-point material layer appears to suppress any micro-material-flow that may occur during overwrite.

Citation Download Citation

Rie Kojima, Takashi Kouzaki, Toshiyuki Matsunaga, and Noboru Yamada "Quantitative study of nitrogen doping effect on cyclability of Ge-Sb-Te phase-change optical disks", Proc. SPIE 3401, Optical Data Storage '98, (23 October 1998); https://doi.org/10.1117/12.327951

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available