DOI QR코드

DOI QR Code

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
강상식;박지군

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

Abstract

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.

Keywords

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

References

  1. Kyung-O KIM, "Measurement of the electrical properties of a polycrystalline cadmium telluride for direct conversion flat panel x-ray detector", 2014 JINST, pp. 1-4, 2014
  2. Kyung-O KIM, et al, "Radiation detector material development with milti-layer by hetero-junction for the reduction of leakage current", The Korean Society of Radiology, Vol. 3, No. 1, pp 11-15, 2009.
  3. Ji-Koon Park, et al, "X-ray sensitivity of hybrid-type sensor based on CaWO4-selenium for digital X-ray imager", Transactions on Electrical and ELectronic Materials, Vol. 5, No. 4, pp 133-134, 2004. https://doi.org/10.4313/TEEM.2004.5.4.133
  4. Ji-Koon Park, et al, "Performance evaluation of a selcenium based prototype digital radiation detector", J. Biomed. Eng, Res, pp. 300-305, 2007.
  5. Heo-Ye-Ji, et al, "A study of the photon counting sensor setup for the evaluation of the photon count efficiency, The Korean Society of Radiology Proceeding of 2012 Autumn conference. pp. 177-180, 2012.
  6. Fred P. Vaccaro, "Limitations of the Hecht equation encountered in measuring $\mu\tau$ products in Mercuric Iodine", Vol. 50, pp. 1-5, 2003.
  7. Safa Kasap, et al, "Amorphous and polycrystalline photoconductors for direct coversion flat panel x-ray image sensors", Sensor, Vol. 11, pp. 5112-5157, 2011. https://doi.org/10.3390/s110505112