Diamond as a unique high-tech electronic material: difficulties and prospects

Diamond is a wide band gap semiconductor with unique electrical, physical, chemical and mechanical properties, opening the possibility to realize, in diamond, electronic devices with unprecedented properties. However, this uniqueness also poses some difficulties specific to diamond. Amongst these are the wide band gap of diamond, the presence of electrically active defects due to sp(2) bonded carbon and unintentionally present impurities, the absence of shallow dopants in diamond ( in particular donors), the presence of extended defects and grain boundaries ( in CVD polycrystalline diamond) and difficulties related to material availability and device processing. Nevertheless, diamond- based prototype devices with promising properties have been realized in the last few years. These include, amongst others, Schottky diodes, field effect transistors, cold electron emission devices and detectors for ionizing radiation, demonstrating the huge potential that this wide band gap semiconductor bears. The uniqueness of diamond, the promise it bears as an unusual material for specific electronic devices and the difficulties related to its application are briefly reviewed. Reference is given to some recent reviews published on specific topics and to some of the more recent breakthroughs and potential applications in the field.