Ultraviolet Detectors Based on Ultraviolet-Ozone Modified Hydrogenated Diamond Surfaces

摘要

Photodetectors based on interdigitated fingers have been fabricated on hydrogen terminated diamond surfaces. These devices show weak photocurrent-to-dark current ratio (PDR ～ 10~(-2)) and persistent photoconductivity making them inappropriate for ultraviolet (UV) detection applications despite high deep UV photocurrent (～10~(-4)A) and a spectral discrimination ratio (210/630nm) of 10~5. However, an original approach combining the previous hydrogen terminated diamond surface with subsequent controlled UV-ozone post-treatments has allowed to respectively enhance the PDR and the discrimination ratio by more than 7 and 2 orders of magnitude while keeping in the same time a high value of deep UV photocurrent (10~(-7)-10~(-8) A).