Vertical Au/ZnO Schottky Barrier Diode Based on High-Resistivity ZnO Film for X-Ray Dose Measurement

Vertical Au/ZnO Schottky barrier diodes (SBDs) were fabricated on an n
⁺
Si substrate and tested as X-ray detectors in this paper. The high-resistivity ZnO film-based SBDs had a large effective area about 0.78 cm
²
and showed a notable sensitivity about 0.78 uC/Gy for X-ray illumination. The detector with linear outputs achieved an X-ray dose measurement across four orders of magnitude of the dose rate from 3.83 mGy/s to 19.00 Gy/s. The response current to switched X-ray illumination exhibited a repeatable and stable characteristic, and the response current mechanism was given and discussed. The results imply the potential of junction devices based on ZnO material for X-ray dose measurement.