Milling Diamond Films

Milling diamond films can be performed with gallium beams. Diamond films, created by first installing tiny diamonds in a pitted silicon surface and then laying down subsequent atoms to form a near-planar diamond surface, have many of the electrical properties of semiconductors, but can operate at much higher temperatures, voltages, and power. Because of its resistance to hostile environments and its bio-compatibility, diamond films are also expected to be act as handy protective coatings in microfluidic research Because of its hardness, however, diamond films are difficult to sculpt through micromachining, during which stresses on the sample can crack the film. Now scientists at the Nanyang Technological University in Singapore have devised a versatile way of making possible micro-optical elements out of diamond films by wielding a carefully focused gallium ion beam. Optical tests of the resultant structures show that such properties as transmission and index of refraction were not distorted by the milling process. By the way, this research was undertaken as part of the Singapore-MIT Alliance, an innovative engineering education and research collaboration established in 1998 among three top engineering research universities: National University of Singapore (NUS), Nanyang Technological University (NTU), and Massachusetts Institute of Technology (MIT). (Fu et al., Review of Scientific Instruments, August 2003)