Smooth diamond surfaces and CMP method for forming

摘要

A method of chemical mechanical polishing (CMP) a diamond containing surface includes providing a slurry including a plurality of particles, at least one oxidizer, and at least one acid, wherein the slurry has a pH≦3 or pH greater than 11. At least an outer surface of the plurality of particles is softer than the diamond surface or the particles are diamond particles averaging less than (<)2 μm in size. The diamond surface is pressed with respect to a polishing pad providing a Shore D Hardness less than 99 having the slurry in between while rotating the polishing pad relative to the diamond surface to form a smooth diamond surface having a root mean square (rms) surface roughness less than 15 nm.

主权项

1. A diamond article, comprising:
a substrate, and
a diamond layer on said substrate having a smooth polished diamond surface, wherein said diamond layer has a thickness from 10 nm to 200 μm:
(i) a root mean square (rms) surface roughness less than (<) 15 nm for an average grain size greater than (>) 0.5 μm, an rms surface roughness less than (<) 10 nm for an average grain size between 50 nm and 0.5 μm, and an rms surface roughness less than (<) 5 nm for an average grain size less than (<) 50 nm, and(ii) a polishing damage index (PDI) less than (<) 109/cm2 wherein said PDI is defined by:
PDI=A−B (in units of #/cm2), wherein A=an average projected surface density of polishing induced defects including dislocations, scratches, pits, and stacking faults in the top “y” microns of said thickness down from said polished diamond surface, and B is the average projected surface defect density at a distance of said “y” microns from said polished diamond surface, and wherein said “y” is 2 microns when said thickness is 3 microns or more, and is one half said thickness when said thickness is less than 3 microns.