The Fabrication and Property Evaluation of Poly-crystalline CdTe based Photon Counting X-ray Sensor

다결정 CdTe 기반의 광계수형 X선 센서 제작 및 특성평가

Kang, Sang Sik;Park, Ji Koon

  • Received : 2015.09.12
  • Accepted : 2015.12.25
  • Published : 2015.12.31


An electrical signals of a conventional radiation medical imaging sensor are obtained by charge integration method. In this study, the polycrystalline cadmium telluride(p-CdTe) film was fabricated by a thermal evaporation method for the photon counting sensor development with excellent resolution in low exposure dose. From the fabricated p-CdTe sensor, the physical properties(SEM, XRD) and the electrical properties(leakage current, x-ray sensitivity, SNR) were evaluated. As a result, the leakage current of below $5nA/cm^2$ and $7{\mu}C/cm^2-R$ of the X-ray sensitivity were showed in below $1V/{\mu}m$. In addition, the signal to noise ratio showed the values of above 5000 at operating voltage.


photon counting;polycrystalline;cadmium telluride;charge collection efficiency;thermal evaporation


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