室温核辐射CdZnTe像素探测器的研制

采用布里奇曼法生长的CdZnTe(CZT)单晶,制成室温核辐射像素探测器.首先通过红外透过显微(IRTM)成像、电阻率测量以及单元探测器能谱响应测试等手段,综合评定了探测器用CZT晶体的质量,结果表明,晶片富Te相密度为28.43 mm-2且尺寸分布较均匀,电阻率为1010 Ω·cm;电子迁移率寿命积为1.07×10-...

Fabrication of room-temperature nuclear-radiation CdZnTe pixel array detectors

The material selection,testing and fabrication technology development of high-performance pixelated CdZnTe(CZT) radiation detectors are reported.The size of the wafer is 10 mm×10 mm×2 mm.The specifications of the anode are 4×4 pixels with a 0.6 mm distance between adjacent pixels.The crystals were evaluated by using infrared microscopy and by being fabricated into planar detectors.The selected crystal has a high resistivity(1010 Ω·cm),high electron transport product(μτe≈1.07±0.02×10-3cm2/V) as well as uniform density and size distribution of inclusions.Pixelated detectors were fabricated employing photolithography,lift-off and electrode deposition.The wet-method passivation and oxidation with low energy atomic oxygen were developed on bared CdZnTe surface.The leakage current of each pixel is between 0.79 nA and 1.2 nA at the bais of 100 V.The γ-ray spectroscopy responses of CZT detectors at different pixels were tested at room temperature using an 241 Am radioactive source with the energy of 59.5 keV.The behaviors of different pixels under radiation were discussed through the Shockley-Ramo theorem.