can be rotated for uniformity of the deposition in all the formations of embodiments one through seven an overall thickness of the underlayer that does not exceed 50 angstroms produces results that meet the objects of the invention an underlayer thickness that is less than 20 angstroms is most preferable although adhesion layers less than 50 angstroms in thickness will meet the objects of the invention subsequent to the deposition of the adhesion layer a layer of dlc not shown is formed on the underlayer using the methods cited above to produce a bonded bilayer that meets the objects of the invention in a second version of the same first embodiment the apparatus of fig5 is used as above but the target material 50 is aln the al nitride rather than the al oxide the ar beam 20 is injected using an rf source and accelerating voltages between approximately 300 v and 1200 v and the o 2 and n 2 gases are injected into the chamber 10 with flow rates between approximately 0 and 20 sccm and different ratios depending upon the desired form of the alo x n y underlayer with x within the range of approximately 0 to 1 5 and y within the range of approximately 0 to 1 as the ar beam strikes the target of aln 50 the resulting sputtered al and n atoms 60 impinge on the read write heads or disks 70 in the presence of the injected o 2 and n 2 gases to produce the desired alo x n y adhesion layer a plurality of the read write heads or a magnetic.