3D-MICRO-ERDA MICROSCOPY OF IMPLANTED H-DISTRIBUTIONS IN DIAMOND

The importance of hydrogen as an impurity in diamond is now widely app reciated. Its apparently vital catalytic role in the metastable synthe sis of diamond, as well as its anticipated significance regarding the electronic properties of future diamond devices are two examples. Desp ite the relevance of hydrogen to both diamond growth and diamond prope rties, 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 informat ion 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 elasti c recoil detection analysis (ERDA) with scanned fine focused heavy-ion beams that allows the total elemental hydrogen distributions in sampl es of known or carefully prepared histories to be quantitatively image d. Details of the mu-scanned-ERDA system based on 25 MeV Cl-35 beams a re presented, and its efficacy demonstrated by comparison to the nucle ar resonance reaction analysis technique in the study of implanted hyd rogen distributions in diamond. In particular, a unique 3D image of a buried hydrogen layer implanted into a synthetic type Ib diamond has b een measured.