Abstract
Ultra-high static pressures have been achieved in the laboratory using a two-stage micro-ball nanodiamond anvils as well as a two-stage micro-paired diamond anvils machined using a focused ion-beam system. The two-stage diamond anvils’ designs implemented thus far suffer from a limitation of one diamond anvil sliding past another anvil at extreme conditions. We describe a new method of fabricating two-stage diamond micro-anvils using a tungsten mask on a standard diamond anvil followed by microwave plasma chemical vapor deposition (CVD) homoepitaxial diamond growth. A prototype two-stage diamond anvil with 300 µm culet and with a CVD diamond second stage of 50 µm in diameter was fabricated. We have carried out preliminary high pressure X-ray diffraction studies on a sample of rare-earth metal lutetium sample with a copper pressure standard to 86 GPa. The micro-anvil grown by CVD remained intact during indentation of gasket as well as on decompression from the highest pressure of 86 GPa.
Disclosure statement
No potential conflict of interest was reported by the authors.