Modifying the Work Function of Magnetic Recording Heads Materials

ANA TARDITI, PETER KONDRATYUK AND ANDREW GELLMAN

Robert hall - Carnegie mellon University - Pittsburgh PA, Estados Unidos

Conferencia; DSSC 2008 Spring Technical Review; 2008

Data Storage System Center

It is known that charging may occur during the operation of magnetic recording heads,resulting from electron transfer from the head material to the media. The extent ofcharging depends, among other factors, on the work function (
) of the recording headmaterial.This project aims to measure the work function of typical recording head materials usingUV Photoemission Spectroscopy (UPS) and identify methodologies that can increase thework function. Emphasis is given to methodologies that can be transferred tomanufacturing conditions.It has been found that the work function is lowered in response to O2 adsorption, contraryto expectations, by about 0.5 eV. The adsorption of a fluorinating agent, XeF2, increasesthe work function by about 0.6 eV. Both changes are reversed after the ceramic materialsample is held in vacuum for several hours.The reversibility indicates that no covalent bonds are formed between the adsorbates andthe diamond-like carbon (DLC) layer on the recording head material under theseconditions.Therefore, the experiments with CF4 plasma fluorination of the samples will be conducted.Covalent functionalization of the DLC surface is expected under those conditions.