AVS 51st International Symposium
    Surface Science Monday Sessions
       Session SS-MoP

Paper SS-MoP23
An in situ XPS Study of Fresh Hydrogenated Amorphous Carbon Films

Monday, November 15, 2004, 5:00 pm, Room Exhibit Hall B

Session: Poster Session
Presenter: Y. Yun, Carnegie Mellon University
Authors: Y. Yun, Carnegie Mellon University
A.J. Gellman, Carnegie Mellon University
Correspondent: Click to Email
In order to develop vapor phase lubrication of hydrogenated amorphous carbon (a-CHx) films for use in hard disk manufacturing insights are needed into the fundamental surface chemistry of vapor deposited lubricants. In vapor phase lubrication, fresh a-CHx will be exposed to lubricants directly. Unfortunately, our current understanding of lubricant surface chemistry on a-CHx is based on studies performed on air-exposed, oxidized a-CHx films. Magnetron sputtering has been used to deposit films in ultra-high vacuum under varying conditions. These films have been characterized by Raman spectroscopy to show that they have characteristics similar to those used commercially. X-ray photoelectron spectroscopy (XPS) was used to study the oxidation of fresh a-CHx during controlled exposure to O2. The film surface saturated at ~20% oxygen after a 20 hour exposure to O2 at 10-4 Torr. One can estimate that under atmospheric conditions where the partial pressure of O2 is roughly 200 Torr, the a-CHx film will be oxidized in a few milliseconds. Thus oxidation of a-CHx is unavoidable between removal of the media from vacuum and dip-coating with lubricant.