First images of a digital autoradiography system based on a Medipix2 hybrid silicon pixel detector
First images of a digital autoradiography system based on a Medipix2 hybrid silicon pixel detector
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DOI：
10.1088/0031-9155/48/12/403
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发表时间：
2003-06-21
影响因子：
3.5
通讯作者：
Russo, P
中科院分区：
文献类型：
--
作者：
Mettivier, G;Montesi, MC;Russo, P
我们展示了使用高分辨率混合像素探测器获得的第一张 β 放射自显影图像，该探测器由凸块接合到 300 微米厚的硅像素探测器的 Medipix2 单光子计数读出芯片组成。该室温系统具有 256 x 256 方形像素，间距为 55 mm（总敏感区域为 14 x 14 mm 2），每个像素中具有双阈值鉴别器和 13 位计数器。它通过专用电子接口和控制软件读出，该软件也是在欧洲 Medipix2 协作框架下开发的。 C-14 微型标准条的数字 beta 放射自显影图（包含在 0.0038-32.9 kBq g(-1) 范围内增加比活度的单独条带）表明系统线性度低至 1.8 x 10(-3) 计数 mm(-2) s(-1) 的总背景噪声。暴露 36 000 秒时，最小可检测活性估计为 0.012 Bq，暴露 10 800 秒时，最小可检测活性估计为 0.023 Bq。测得的最小检测阈值小于 1600 个电子（相当于约 6 keV Si）。与之前基于 Medipix 1 的系统相比，这款用于 beta 放射自显影的实时系统提供了更低的像素间距和更高的敏感区域。它的 C-14 灵敏度优于基于微通道板的系统，但具有更高的空间分辨率和敏感面积。
We present the first images of beta autoradiography obtained with the high-resolution hybrid pixel detector consisting of the Medipix2 single photon counting read-out chip bump-bonded to a 300 mum thick silicon pixel detector. This room temperature system has 256 x 256 square pixels of 55 mum pitch (total sensitive area of 14 x 14 mm 2), with a double threshold discriminator and a 13-bit counter in each pixel. It is read out via a dedicated electronic interface and control software, also developed in the framework of the European Medipix2 Collaboration. Digital beta autoradiograms of C-14 microscale standard strips (containing separate bands of increasing specific activity in the range 0.0038-32.9 kBq g(-1)) indicate system linearity down to a total background noise of 1.8 x 10(-3) counts mm(-2) s(-1). The minimum detectable activity is estimated to be 0.012 Bq for 36 000 s exposure and 0.023 Bq for 10 800 s exposure. The measured minimum detection threshold is less than 1600 electrons (equivalent to about 6 keV Si). This real-time system for beta autoradiography offers lower pixel pitch and higher sensitive area than the previous Medipix 1-based system. It has a C-14 sensitivity better than that of micro channel plate based systems, which, however, shows higher spatial resolution and sensitive area.