X-선촬영 조사 조건하에서 다결정 요오드화수은 박막검출기의 신호특성 분석
Analysis of the Signal Properties of Polycrystalline HgI2 Film Detector under Radiographic Irradiation Condition
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이 연구의 목적은 다결정 요오드화수은 박막검출기를 제작하여 X-선촬영 조사 조건하에서 검출기 성능의 평가이다. 두께 210과 320㎛를 갖는 다결정 요오드화수은 박막검출기들은 스크린 프린트 기술로 제작하였다. X-선 감도와 암전류의 측정들은 두 검출기에 대하여 수행하였다. 그리고 X-선 반응의 선형성과 재현성의 측정들은 두께 320㎛의 검출기에 대하여 수행하였다. 두께 320㎛의 검출기에 인가된 0.05에서 2V/㎛까지의 전기장 강도들에 대하여, X-선 감도들은 233에서 1,408×106 electrons/mR․mm2까지 측정되었다. 그리고 암전류들은 3.2에서 118pA/mm2까지 측정되었다. Zhong Su 등에 의해 보고된 값들과 비교에서, X-선 감도들은 Zhong Su 등에 의해 측정된 X-선 감도들보다 약 2배 더 크게 나타냈다. 그리고 암전류들은 Zhong Su 등에 의해 측정된 암전류들보다 약 9배 더 크게 나타냈다. X-선 반응의 선형성은 상관계수(r)로서 0.988을 얻었다. 재현성은 변동계수로서 0.002를 얻었다. 이 연구는 X-선촬영 조사 조건하에서 능동매트릭스 평판영상장치에 사용할 수 있는, 제작된 다결정 요오드화수은 박막검출기의 성능 데이터를 제공한다.
Abstract
The purpose of this study is an evaluation of the performance of a detector under radiographic irradiation condition by fabricating the polycrystalline HgI2 film detector. The polycrystalline HgI2 film detectors with thickness of 210 and 320㎛ were fabricated by screen print technology. Measurements of X-ray sensitivity and dark current were performed for two detectors. And measurements of the linearity of X-ray response and reproducibility were performed for the detector of thickness 320㎛. For applied electric field strengths from 0.05 to 2V/㎛ to the detector of thickness 320㎛, the X-ray sensitivities were measured from 233 to 1,408×106 electrons/mR․mm2. And the dark currents were measured from 3.2 to 118 ㎀/㎟. Compared with values reported by Zhong Su et al., the X-ray sensitivities exhibit about two times larger than the X-ray sensitivities measured by Zhong Su et al. And the dark currents exhibit about nine times larger than the dark currents measured by Zhong Su et al. The linearity of X-ray response acquired 0.988 as a coefficient of correlation (r). Reproducibility acquired 0.002 as a coefficient of variation. This study provides the performance data of fabricated polycrystalline HgI2 film detector available for an active matrix flat panel imager under radiographic irradiation condition.
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