Post-growth treatments and contact formation on CVD diamond films for electronic applications

摘要

Radiation detectors have been fabricated from undoped polycrystalline diamond films deposited usingmicrowave chemical vapour deposition (CVD). We have investigated the influence of post-growthtreatments on the detection and on the electronic properties of CVD diamond devices. The effects ofvarious treatments, including a series of surface preparations and thermal annealing, are reported.The study was performed on devices fabricated with carbide- as well as non-carbide-forming contactmaterials. Devices were characterised according to the dark conductivity as well as to the alphaparticle induced conductivity (CPIC technique). The study highlights the strong effects of thesetreatments on the detection efficiency. From the sets of results it appears that surface effects arepredominant over bulk material modifications or hydrogen redistribution during annealing. Thisreinforces the need for optimised contact formation and post treatment, for electronic and radiationdetection applications.