3D-microERDA microscopy of implanted H-distributions in diamond

The importance of hydrogen as an impurity in diamond is now widely appreciated. Its apparently vital catalytic role in the metastable synthesis of diamond, as well as its anticipated significance regarding the electronic properties of future diamond devices are two examples. Despite the relevance of hydrogen to both diamond growth and diamond properties, comparatively little is known about it, and it has proven to be a most elusive impurity to study. In order to gain a complete picture of hydrogen behaviour in diamond, hydrogen molecular complex information available by conventional spectroscopies needs to be supplemented by observations of the total elemental concentration. To address this problem we have developed a system to perform three-dimensional elastic recoil detection analysis (ERDA) with scanned fine focused heavy-ion beams that allows the total elemental hydrogen distributions in samples of known or carefully prepared histories to be quantitatively imaged. Details of the μ-scanned-ERDA system based on 25 MeV ³⁵Cl beams are presented, and its efficacy demonstrated by comparison to the nuclear resonance reaction analysis technique in the study of implanted hydrogen distributions in diamond. In particular, a unique 3D image of a buried hydrogen layer implanted into a synthetic type Ib diamond has been measured.