Diamonds are an engineers best friend

In recent years, diamond has emerged as not only a girl’s best friend, but also as contender as an engineer’s best friend – if the technical challenges of exploiting its remarkable properties can be overcome.

Due to the extraordinary properties of diamond, nanocrystalline diamond films have found application in Micro-Electro-Mechanical Systems (MEMS), Surface Acoustic Wave (SAW) devices, thermal management and tribological coatings.

These applications all require for diamond films to be grown on silicon wafers and herein lies a key challenge – diamond does not grow epitaxially on silicon, requiring wafers to be seeded with nanodiamond particles prior to growth. The competitive growth process that follows leads to a rough surface finish that can be detrimental to its key applications.

In order to overcome this surface roughness, a team of researchers from Cardiff University, Imperial College and the University of Oxford developed a new process to significantly reduce the surface roughness of the films.

Using Logitech’s Tribo benchtop CMP instrument, the researchers developed a process that used a polyurethane/polyester polishing cloth and an alkaline colloidal silicon fluid.

The surface was characterised using Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM) and X-ray Photoelectron spectroscopy to reveal the process had reduced the root mean square roughness from 18.3 nm to 1.7 nm over 25um².

To learn more about the research, simply click here